Greece, like the rest of the Mediterranean countries, faces wildland fires every year. Besides their short-term socioeconomic impacts, ecological destruction, and loss of human lives, forest fires also increase the burnt areas’ risk of flash flood phenomena, as the vegetation, which acted in a protective way against runoff and soil erosion, is massively removed. Among the most severe wildland fire events in Greece were those of summer 2021, which were synchronous to the very severe heat waves that hit the broader area of the Balkan Peninsula. More than 3600 km2 of land was burnt and a significant amount of natural vegetation removed. Three of the burnt areas are examined in this work, namely, Attica, Northern Euboea, and the Peloponnese, in order to assess their risk of future flash flood events. The burnt areas were mapped, and their geological and geomorphological features studied. Flash flood hazard assessment was accomplished through a Boolean logic-based model applied through Geographic Information Systems (GIS) software, which allowed the prioritization of the requirement for protection by identifying which locations were most prone to flooding. The largest part of our study areas is characterized by geomorphological and geological conditions that facilitate flash flood events. According to our findings, in almost all study areas, the regions downstream of the burnt areas present high to very high flash flood hazard, due to their geomorphological and geological features (slope, drainage density, and hydrolithology). The only areas that were found to be less prone to flood events were Vilia and Varimpompi (Attica), due to their gentler slope inclinations and overall geomorphological characteristics. It is known that vegetation cover acts protectively against flash floods. However, in this case, large areas were severely burnt and vegetation is absent, resulting in the appearance of flash floods. Moreover, imminent flooding events are expected to be even more intense in the areas downstream of the burnt regions, possibly bearing even worse impacts on the local population, infrastructure, etc.

Pocket beaches are a large part of the Greek coastline, with strong touristic, economic and natural interest. Their morphological characteristics and wave forcing are the main factors influencing their evolution, while the most commonly observed dynamic is beach rotation due to prevailing wave direction. Human activities and climate change call for a better management for these areas, necessitating, therefore, the identification of coastal geomorphodynamic processes. This paper focuses on the geomorphological and sedimentological dynamic processes of Platis Gialos Bay (Sifnos), which have given rise to the present setting. Beach orientation, slope, length, geology, Posidonia Oceanica, degree of embayment, sedimentology and closure are some parameters that must be considered to calculate the morphodynamic and stability indicators that prevail at the beach. Wave exposure forcing conditions, longshore – rip current direction, are also hydrodynamic processes to be determined, as they play a significant role in sediment transport. A number of methodologies took place in order to determine the level of disturbance of this dynamic equilibrium, which included morphological mapping, sedimentary classification, shoreline displacement/evolution monitoring, hydrodynamic and sedimentary modelling. The exposure of the coast to the southern waves, the reduced sediment supply from the local fluvial network, human activities and the construction of the fishing shelter have led the area to a continuous erosion and coastline retreat in its western and central part, in contrast to the eastern part, where there is a continuous deposition reflected by coastal accretion and the formation of a shallow environment.

Myrtos Beach (Cephalonia Island, Ionian Sea, Greece) represents a pocket beach with strong touristic, economic and natural interest. In this research, the morphodynamic behavior of the coastal area (e.g., hydrodynamic and sedimentary state, morphology, orientation, etc.), the current wave conditions (extreme and dominant waves, wave exposure), and also external factors, such as human impact and the geotechnical condition of the wider area, are examined. Short- and medium-to-long-term analysis took place, such as mapping, sediment analysis, wave/wind analysis, numerical modeling, and satellite monitoring, in order to identify the dynamic forcing parameters related to geomorphology, sedimentology, and hydrology that prevail in the area. Additionally, the intense tectonics, the karstified limestones, and the steep slopes of the cliffs in combination with the frequent seismic events on the island set up a geotechnically unstable area, which often cause landslides on the beach of Myrtos; these supply the beach with a large amount of aggregates, constituting the main sediment supply. Wave exposure forcing conditions, longshore–rip current direction, and other hydrodynamic processes are stable with high values in the area, causing notable sediment transport within the bay boundaries. As a result, at Myrtos Bay there is a dynamic balance of the natural system, which is directly affected by human interventions. Taking also into consideration that Myrtos is one of the most famous beaches in Greece and one of the main attractions of Cephalonia Island with thousands of visitors every year, beach management must be focused on preserving the natural system of the coastal area.

Geoscience courses, such as geology and geomorphology, require not only classroom lessons and laboratory exercises, but field trips as well. However, the COVID-19 restrictions did not allow the execution of most planned field trips, and an alternative needed to be developed. The use of virtual field trips is one such alternative. Through this research, we evaluate the usefulness of virtual field trips as tools for preparatory activities before an actual field trip takes place in the same area, and their contribution in providing a better understanding of geomorphological processes and landscape evolution. We performed a virtual navigation on the island of Naxos, Cyclades (Aegean Sea, Greece) for a series of virtual field trips, which took place during webinars in the framework of Erasmus+ CIVIS. The virtual field trip was also presented to the third-year students of the Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens, in the framework of the obligatory course of Geomorphology. Upon completion, all participating students were asked to fill in a questionnaire in order to evaluate the contribution of virtual field trips to their education regarding geomorphology and state their opinion as to whether they can supplement and/or substitute actual field trips. According to the results, virtual field trips can aid, but not substitute, the actual field trip. Most students mentioned that they would attend another virtual field trip in the future, both as an alternative to classroom lessons and as a means of preparation for an actual field trip, but not in order replace the actual one. Virtual field trips can significantly support the realization of actual ones, by introducing the necessary tectonic, geological and geomorphological background of a particular study area and offering more time for practical activities or field methodologies during the actual field trip.

Combined with eustatic sea-level changes, uplifted Quaternary marine terraces provide insight into the tectonics of coastal areas. Cephalonia Island lies 35 km off the western coast of mainland Greece and 15 km northeast of the Hellenic subduction zone. Late Pleistocene eustatic sea-level oscillations and the long-term tectonic movements are imprinted on the landscape of the southern part of the island, in the form of seven uplifted marine terraces. In the present study we aim to identify and map in detail these terraces, applying Digital Elevation Model analysis, utilizing Geographic Information Systems techniques and extensive fieldwork. The GIS-based analysis combined with field geomorphological observations revealed a sequence of seven marine terraces at the southern part of the main island ranging in elevation between 4 m and 176 m asl. Microscope, petrological and microgeomorphological analyses on two caprock samples suggest strong marine influence during the deposition of the sediments covering the marine terraces. The age of the formation of the 32 m marine terrace was assigned to the MIS 3e, based on OSL dating of a caprock sample, and an average uplift rate of 1.4 ± 0.35 mm a−1 was calculated for the last 61 ± 5.5 ka. Assuming a uniform uplift rate for the Late Pleistocene allowed us to correlate the marine terrace with the sea-level highstands and constrain their ages.

The wildfires of summer 2021 in Greece were among the most severe forest fire events that have occurred in the country over the past decade. The conflagration period lasted for 20 days (i.e., from 27 July to 16 August 2021) and resulted in the devastation of an area of more than 3600 Km2. Forest fire events of similar severity also struck other Mediterranean countries during this period. Apart from their direct impacts, forest fires also render an area more susceptible to runoff erosion by massively removing its vegetation, among other factors. It is clear that immediately after a forest fire, most areas are much more susceptible to erosion. In this paper, we evaluate the erosion hazard of Attica, Northern Euboea, and the Peloponnese that were devastated by forest fires during the summer of 2021 in Greece, in comparison with their geological and geomorphological structures, as well as land cover and management. Given that a very significant part of these areas were burnt during the major conflagrations of this summer, erosion risk, as well as flood risk, are expected to be very high, especially for the coming autumn and winter. For the evaluation of erosion risk, the burnt areas were mapped, and the final erosion-risk maps were constructed through GIS software. The final maps suggest that most of the burnt areas are highly susceptible to future surface runoff erosion events. View Full-Text

Beachrocks are a window to the past environmental, geological, sedimentological and morphological conditions that were dominant in the coastal zone during their formation. Furthermore, beachrocks have the ability to reduce coastal erosion impact on sandy beaches. This study focuses on the beachrock formation mechanism through the comparison of cement characteristics, mineral chemistry and sedimentology of beachrock occurrences from two different geological and geographical localities: Diolkos, Corinth, Greece and Sumuide, Okinawa, Japan. In addition, in order to investigate a potential soft engineering method to protect coasts from erosion, artificial beachrock samples were created in vitro using sand samples and ureolytic bacteria from both areas under accelerating conditions. For Okinawa artificial beachrock experiments, the bacteria Pararhodobacter sp. was used, and for Diolkos, it was the bacteria Micrococcus yunnainensis sp. For the natural beachrocks, a multi-analytical approach was accomplished with the use of microscopic investigation, a scanning electron microscope, energy-dispersive X-ray spectroscopy, X-ray diffraction and X-ray fluorescence. Correlations were made between natural and artificial beachrocks. Results have shown that Diolkos beachrock was formed in the upper part of the intertidal zone, consisting of detrital material originating from the local bedrock, while Sumuide beachrock formed in the low intertidal–upper subtidal zone, consisting of coral sand and foraminifera fragments. For the artificial beachrocks, three samples were created using the microbial-induced carbonate precipitation (MICP) method, one from Diolkos (Corinth, Greece) and two from Sumuide (Okinawa, Japan). Diolkos artificial beachrock was better consolidated in comparison to Sumuide. Our investigation has shown that bacterial density was the key factor for the creation of the artificial beachrocks, while the samples’ granulometry played a secondary role in the process. The laboratory artificial beachrocks show encouraging results for a new soft engineering method to encounter beach erosion while keeping an ecofriendly character by saving energy, material resources and gas emissions. Artificial beachrocks can share the same properties of a natural beachrock and can contribute positively to marine biodiversity as a natural rocky habitat.

Soil improvement via MICP (microbially induced carbonate precipitation) technologies has recently received widespread attention in the geoenvironmental and geotechnical fields. The durability of MICP-treated samples remains a critical concern in this novel method. In this work, fiber (jute)-reinforced MICP-treated samples were investigated to evaluate their durability under exposure to distilled water (DW) and artificial seawater (ASW), so as to advance the understanding of long-term performance mimicking real field conditions, along with improvement of the MICP-treated samples for use in coastal erosion protection. Primarily, the results showed that the addition of fiber (jute) improved the durability of the MICP-treated samples by more than 50%. Results also showed that the wet–dry (WD) cyclic process resulted in adverse effects on the mechanical and physical characteristics of fiber-reinforced MICP-treated samples in both DW and ASW. The breakdown of calcium carbonates and bonding effects in between the sand particles was discovered to be involved in the deterioration of MICP samples caused by WD cycles, and this occurs in two stages. The findings of this study would be extremely beneficial to extend the insight and understanding of improvement and durability responses for significant and effective MICP treatments and/or re-treatments.

Degradation of coastal environments is an issue that many areas in Europe are facing. In the present work, an ancient coastal lake wetland is investigated, the so-called Lake Lerna in NE Peloponnese, Greece. The area hosted early agricultural populations of modern Greece that started modifying their environment as early as the early–middle Neolithic. Two drill cores in the area of the ancient lake were analysed to establish the sedimentological succession and the depositional environments using sub-fossil assemblages (molluscs and ostracods). Three lithological and faunal units were recovered, the latter being confirmed by the statistical ordination method (non-metric multidimensional scaling). The usage of sub-fossil mollusc species for the first time in the region enriched the dataset and contributed significantly to the delimitation of the faunas. These consist of environments characterised by various levels of humidity (from stagnant waters to freshwater lake) and salinity, with ephemeral intrusions of salt water to the lake, documented by mollusc and ostracod populations. We conclude that the lake and its included fauna and flora were mostly affected by climatic fluctuations rather than human intervention in the area.

The aim of the research is the awakening, participation and alertness of educators and students of Primary Education schools in Greece when it comes to rapid onset Natural Disasters pre-emption. The aim is the alertness of educators, as well as students of school units, so that they are able to face rapid onset natural disasters with prudence and composure, both during them, by putting themselves in the minimum possible danger, and after their finish, by taking part in the rehabilitation of “damages” of any kind. At an early stage, through the distribution of two questionnaires, one for educators and one for students, we invited the participants to answer questions relevant to their status and knowledge, when it comes to rapid onset natural disasters and their safe living in their school environment. In total, the participants exceeded two thousand (2,000) persons. One thousand twenty seven (1,027) educators, serving the Primary Education, and nine hundred eighty four (984) random students from all over the country, answered the digital questionnaires created through the application ArcGIS Survey123 (part of Geospatial Cloud by Esri), which is an integrated solution to the creation, distribution and analysis of survey data. From the statistical analysis of their answers, their beliefs regarding the subject examined arose and the proposed means of action is profiled, so that persons participating on the educational procedure can achieve their meaningful training, in order for them to feel safer and more aware, imparting their knowledge regarding rapid onset natural disasters. Their considering training programs about natural disasters necessary is clear, as the majority of them accept that any natural disaster is liable to occur while they are at school. The conducted research showed that the knowledge of educators and students regarding their responsibilities, as well as the necessary items and services which are essential during the occurrence of the natural phenomenon, as well as after its finish, seem to be inadequate.

The Kastrouli Late Bronze settlement in Phocis province, central Greece, has been proved to have been an important center in the periphery of the Mycenaean palaces. It was reused at least partially and was cultivated until the 20th century. The presence of a flat area off the Kastrouli hill and the seasonal flooding nowadays led to the present investigation, questioning the formation of an ancient lake or marsh/swamp. A methodological approach was applied combining the digital elevation model (DEM) and GIS of the wider and confined area, examining slopes between 0 and 5 degrees (0 and 8.75%), with electrical resistivity tomography (ERT) traverses of around 300 and 500 m, reaching a depth of 100 m. The ERT data were rapidly collected on profiles and provided a cross-sectional (2D) plot. It was found that, in the area, there is a basin with a length of 100 m and a depth of around 40–50 m. The sedimentation process over the millennia has filled the basin, with the upper 5–6 m surface layers of the area having a low resistivity. The presence of two natural sinkholes with apparent engineered hydraulic works is noted to conform to drainage and produce a habitable environment, protecting the cultivated land and avoiding a swamp associated with health issues.

Beachrocks are well known as significant proxies for paleoenvironmental analysis as they indicate the coastal evolution. The combination of geomorphological and archaeological sea level indicators has a significant contribution to the coastal paleogeographic reconstruction. In this study, we studied a beachrock from the Diolkos area (West Corinth canal, Greece) and remnants of Diolkos slipway to reconstruct the coastal evolution before Diolkos construction until today. We conducted detailed mapping of Diolkos beachrock using DGPS-GNSS, as well as mineralogical analysis and OSL dating of beachrock samples. The results showed that a beachrock slab was preserved before the construction of Diolkos below it, followed by its submergence by a co-seismic event after Diolkos abandonment during 146 B.C. Consequently, a new beachrock was developed on top of the submerged Diolkos around 120 ± 14 A.D. The RSL was stable until 1596 ± 57 A.D. when the beachrock developed even closer to the present-day coastline. After 1596 A.D., it was uplifted by 12 cm until it reached today’s condition.

Cyprus has a long history of tsunami activity, as described in archaeological and geological records. Although the study area has experienced tsunamis in the past and constitutes an area threatened by this hazard both from the Cyprean arc and from the neighboring Hellenic arc, field research on tsunami evidence on the coastal zone of Cyprus still remains scarce. It is clear from the literature that large boulder accumulations are an important feature along the coasts of Cyprus, testifying to extreme events. A detailed field survey revealed that at various locations cited in the literature as hosting geomorphological evidence of past tsunamis, no such evidence was identified. It is likely that the high touristic activity that has been occurring on the coasts of Cyprus during the last 20 years may have affected tsunami indicators such as boulder accumulations. Tsunamis are unpredictable and infrequent but potentially large-impact natural disasters. The latest strong tsunami that caused damage to the Cypriot coast was centuries ago, when the population and economic growth and development at the Cypriot shoreline did not exist. Today, the coastal zone hosts a higher population as well as increasing touristic activity, highlighting the need for better preparedness, awareness raising and for tsunami-related risk reduction. 

Geoscience courses, such as geology and geomorphology, require not only classroom lessons and laboratory exercises, but field trips as well. However, the COVID-19 restrictions did not allow the prosecution of most planned field trips, and an alternative needed to be developed. The use of virtual field trips is one such alternative. Through them, one can not only visit any area of interest, but prepare themselves for any actual educational or exploratory field trip as well. Even though they do not, and should not, substitute any physical visit of a site of interest, they have many advantages when combined with a "live" field work, in comparison to a field trip for which no preparation has been made.Through this research, we compare the advantages and disadvantages of both virtual and real educational field trips based on the opinions of our students. We thus performed a virtual navigation on the island of Naxos, Cyclades (Aegean Sea, Greece) for a series of virtual field trips, which took place during webinars in the framework of Erasmus+ CIVIS. The virtual fieldtrip was also presented to the third-year students of the Faculty of Geology & Geo-environment, National and Kapodistrian University of Athens, in the framework of the obligatory course of Geomorphology. Upon completion, all participating students were asked to fill in a questionnaire in order to evaluate the contribution of virtual field trips to their education regarding geomorphology and state their opinion as to whether they can supplement and/or substitute actual field trips. Most of them stated that virtual field trips can aid, but not substitute the actual field work. Most students mentioned that they would attend another virtual field trip in the future, both as an alternative to classroom lessons and as a means of preparation for an actual field trip, but not in order not to attend the actual one.

Field trips are an essential part for geoscience students, as the field is intrinsic for understanding what they are taught in the classroom. Yet, distance learning has never been more necessary than today. Despite their significance in the students’ education, field trips cannot be performed under the present conditions with the COVID-19 pandemic. Educators are called to find, use and evolve various tools in order to offer students quality education, with an effort to eliminate the drawbacks of the lack of physical contact and “live” field work. Virtual field trips are one such tool through which one can virtually see any place on the globe by means of a computer, tablet, or even mobile phone, without physically visiting it. In this paper, we present the results of a virtual field trip developed for students following the Geomorphology course of the Faculty of Geology and Geoenvironment, National and Kapodistrian University of Athens; it can, however, be used from other universities with similar courses not only in Greece but also in other countries as well. The purpose of this study is the evaluation of virtual field trips, both as an alternative to and/or substitute for in situ field work and as a means of preparation for live field trips, by taking into consideration the students’ views through an anonymous questionnaire. Our findings suggest that virtual field trips are useful for geoscience students, and they provide a good alternative during restriction periods, and although they can under no circumstances substitute real field trips, they can be a valuable additional tool when preparing for a live field trip.

In some islands of the Aegean, there is evidence of the occurrence of repeated rapid subsidences during the Late Holocene. In this paper, the shape of tidal notches that may be well-preserved underwater is recalled in order to reconstruct sequences of coseismic subsidences and other relative sea-level changes, which occurred during, at least, the last few millennia. A reanalysis of the published measurements of submerged tidal notches in several islands reveals that subsidence trends in many areas of the Aegean are not continuous with gradual movement but, also, are the result of repeated coseismic vertical subsidences of some decimetres at each time. The estimated average return times are of the order of approximately some centuries to one millennium. Although the results cannot be used for short-term predictions of earthquakes, they may provide useful indications on the long-term tectonic trends that are active in the Aegean region.

On 30th October 2020, the eastern Aegean Sea was shaken by a Mw = 7.0 earthquake. The epicenter was located near the northern coasts of Samos island. This tectonic event produced an uplift of the whole island as well as several cases of infrastructure damage, while a small tsunami followed the mainshock. Underwater and coastal geological, geomorphological, biological observations and measurements were performed at the entire coast revealing a complex character for the uplift. At the northwestern part of the island, maximum vertical displacements of +35 ± 5 cm were recorded at the northwestern tip, at Agios Isidoros. Conversely, the southeastern part was known for its subsidence through submerged archaeological remains and former sea level standstills. The 2020 underwater survey unveiled uplifted but still drowned sea level indicators. The vertical displacement at the south and southeastern part ranges between +23 ± 5 and +8 ± 5 cm suggesting a gradual fading of the uplift towards the east. The crucial value of tidal notches, as markers of co-seismic events, was validated from the outcome of this study. The co-seismic response of Samos coastal zone to the 30th October earthquake provides a basis for understanding the complex tectonics of this area.

Raising awareness for sustainable development and environmental consciousness is an alternative teaching approach of geosciences in primary education. Through our methodology this is achieved by strengthening teachers' profile to effectively coach students to work on several environmental issues. By creating a teacher’s guideline handbook, in accordance with the educational targets and regulations of EU countries, teachers acquire a fresh perspective on teaching environmental sciences. They also gain scientific knowledge in five educational topics through the implementation of five mini-projects. An e-book enriched with the pupils’ digitalised environmental stories was designed to attract students and motivate them to engage environmental issues. The final product acts as a triggering factor for the much-needed environmental awareness of pupils around Europe.

Cyprus has a long history of tsunami events, as noted by archaeological and geological records. At Cape Greco (southeastern Cyprus) large boulders have been noted, however, no detailed geomorphological research has taken place so far and the related high energy event was undated until now. Our research aims to record in detail and interpret these large boulders deposits. The boulders, located between ≈3 and 4.5 m a.m.s.l., are fragments of an upper Pleistocene aeolianite, which is overlaying unconformly a lower Pleistocene calcarenite. Dimensions and spatial distribution of 272 small, medium, and large boulders were documented, while their precise distance from the coastline was recorded by field mapping and remote sensing, using Differential GPS (DGPS), drone, and Geographic Information Systems (GIS) technics. Field data were subsequently combined with hydrodynamic equations, in order to determine the extreme event(s) that caused their transport inland, and radiocarbon dating was accomplished on three samples of Vermetus sp. to determine the chronological context. Our findings appear to broadly correlate with the 1303 AD tsunami, which has displaced at least part of the studied boulders, and one other undocumented event at AD 1512-1824. The large number of boulders and sizes in our study area further indicate that their dislocation is most likely owed to multiple events from various sources.

Considering the global climate change and the ensuing sea level rise, the subsequent acceleration of coastal erosion is evident. Phenomena of coastal erosion, coastal flooding and shoreline retreat are expected to show a significant increase in frequency and intensity, in global level. The effects of coastal erosion are worsened by storms, and the reduction of sediment supply associated with global warming and anthropogenic modification of rivers and coastlines. As a countermeasure to coastal erosion, this work focuses on the development of coastal artificial in-situ rocks. We developed a new method that encompasses microbes and the related mechanism is called “Microbial Induced Carbonate Precipitation” (MICP). We successfully isolated three microorganisms, Micrococcus sp., Pseudoalteromonas sp., and Virgibacillus sp., from the selected area, and investigated their effectiveness in order to make a solidified sand sample. The precipitated bounding material has also been confirmed as calcite by XRD and XRF analysis. We successfully demonstrated that all of these bacterial species are very sensitive with certain environmental parameters, such as temperature, pH, culture type, culture duration, etc. In laboratory scale, we successfully obtained solidified sand by syringe (d = 2.3 cm, h = 7.1 cm) solidification method bearing UCS (Unconfined Compressive Strength) up to 1.8 MPa using 0.5 M CaCl2 and urea as cementation solution at 30°C. In addition, we propose a new sustainable approach for field implementation of this method through a combination of geotube and MICP mechanism, which will contribute to coastal erosion protection. The proposed approach is more economic, energy-saving, eco-friendly, and sustainable for bio-mediated soil improvement.

Greece and the Aegean area are among the first areas in Europe to have been occupied by humans. The record of human interventions in natural environments is thus particularly rich. Some of the interventions of the people inhabiting various localities of the country have been recorded in local mythology. Through the interdisciplinary field of geomythology it is possible to attempt to uncover the relationships between the geological history of early civilizations and ancient myths.In the present work, we focused on the history of Lake Lerni in the Eastern Peloponnese, an area that is better known through the myth of Hercules and the Lernaean Hydra. The area of the lake – now dried and cultivated – was part of a karstic system and constituted a marshland that was a source of diseases and needed to be dried.A new core is studied from the area of modern-day Lerni using palaeontological methods in order to reconstruct environmental changes that occurred during the last 6.000 years approximately. The area is known to have gone from marsh-lacustrine environments to dryer environments after human intervention or the intervention of Hercules according to mythology. Levels of peat considered to represent humid intervals were dated using the radiocarbon method so as to have an age model of the core. Samples of sediment were taken every 10 cm; the grain size was analysed for each sample as well as the fossil content for the environmental reconstruction.The presence of numerous freshwater gastropods reflects the intervals of lacustrine environment accompanied with extremely fine dark sediment. Sedimentology is stable throughout the core with few levels of coarse sand/fine gravel, only changes in colour hint to multiple levels richer in organic material.

Marathon Lake is an artificial reservoir with great environmental, ecological, social, and economic significance because it was the main source of water for Athens, the capital of Greece, for many years. The present study details the first attempt to map sedimentation in Marathon Lake in detail, using bathymetric mapping and soil erosion field surveying of the torrent watershed areas. First, the results of a bathymetric survey carried out in 2011 were compared with topographic maps that pre-date the construction of the dam. Based on this comparison, an estimated 8.34 hm3 of sediment have been deposited in the 80 years since the dam’s construction. In the current survey, the Revised Universal Soil Loss Equation (RUSLE) was used to estimate soil loss in the watershed area of the streams that end in Marathon Lake. The estimated value from the RUSLE was substantially lower (3.02 hm3) than that calculated in the bathymetric survey.

Cyprus has a long record of tsunami waves, as noted by archaeological and geological records. Large boulder deposits have been noted in the southeastern and western part of the Island. At Cape Greco (southeastern Cyprus) large boulders have been noted, however, no detailed geomorphological research has taken place so far and the related high energy event remains undated. Our research focuses at Cape Greco Peninsula in order to record in detail and interpret the large boulders deposits. The boulders, located at 3 m amsl, are fragments of a layer of an upper Pleistocene aeolianite, which is overlaying unconformly a lower Pleistocene calcarenite. Dimensions and spatial distribution of 272 small, medium and large boulders were documented, while their precise distance from the coastline was recorded by field mapping and remote sensing, using GNSS, drone and GIS technics. Several large boulders weighting more than ~30 metric tons were found up to 60m inland. Geomorphologic mapping and morphometric measurements, along with the presence of marine organisms suggests that some of the boulders were removed from their original intertidal zone and were transported inland by the force of large waves. In this work, we attempt to determine the extreme event that caused their transport inland. We further attempt a correlation of the event with already known tsunami events from Eastern Mediterranean, based on the estimated wave heights and the radiocarbon dating of marine gastropods (Vermetus sp.).

Two well-developed quaternary sand dune fields have been identified on the western and eastern side of Akrotiri promontory (Lemesos, Cyprus). The fields extend immediately from the low level of their source beaches onto higher ground (> 38m amsl). Geomorphic observation supported by OSL dating of multimineral sand horizons demonstrate several phases of sand accumulation in the western field in contrast to the smaller eastern system, where the evidence direct to a relatively recent dune emplacement. The effects of climatic change, relative sea-level change and anthropogenic influence in dune evolution, have been evaluated in both sites in combination with documented evidence of human induced destabilization of the western sand dune field during the 1970s and 1980s. Both fields share similar topographic settings and situated in close proximity but they do not share an entirely similar evolution history. The  οbservations and the data suggest the combination of local and regional control of the development of the sand dunes and the geochronological analysis with luminescence methodology support the ability of the method to reconstruct the evolution of sand dunes fields in the eastern Mediterranean area.

Akrotiri Penisnsula is located west of Limassol at the Southern end of the Island of Cyprus. It covers an area of approximately 100km². The development of the peninsula started with the deposition of calcareous marls in to the Episkopi grabben during the Miocene which resulted the Akrotiri High in the form of an isolated island. The maritime space between the Akrotiri Island and the mainland eventually closed during the Quaternary and several geomorphic features were developed. Beachrocks identified at three continuous pocket beaches at the southwest part of the Akrotiri peninsula. Detailed GNSS measurements and GIS analysis revealed that the area is uplifted. A direct relationship between the development of the beachrocks and the paleogeographic evolution of the area is apparent. Additionally, results from Petrographic, mineral and sedimentary analysis on beachrock samples are indicating a continuous supply of material from the nearby Kouris River. A gradual reduction of the sediment granulometry consists the beachrock is observed. Also the transition of the texture of the samples from non-uniform to uniform is observed. The sample mineralogy varies eg quartz, alkaline feldspars, carbonate minerals, ortho and clino pyroxenes, serpentinites, hornblende, muscovite. A reduction in the contribution of overbearing minerals (according to their hardness) was observed from North to Southern beachrock slabs and the increase of carbonates, quartz and feldspart. It should be noted that there is a strong participation of fossils fragments were a number of them was preserved in good condition. SEM-EDX analysis were conducted and showed that the micritic and sparitic crystals of cement are consisted by High Magnesium Calcite +(>4 mol% CaCO3 or 1.2 wt.). The cement agent forms an isopachous coating around the sediment grains and with meniscus forms connect all the sedimentary particles which leads to the formation of a high density beachrock slabs.

Beachrocks are hard coastal sedimentary formations consisted from various beach sediments, coastal fauna residues and anthropogenic articles. Beachrocks are rapidly cemented through precipitation of carbonate cements typically consisted of High-Magnesian Calcite (HMC), which commonly precipitates in shallow marine environments, (>4 mol % CaCO3 or 1.2 wt. %) or aragonite (Ar). However, debate still exists concerning the accurate depositional environment of beachrocks and data for the mechanism of their formation are considered necessary. This study aims to contribute to the understanding of the beachrock formation, using mineralogical and geochemical methods, analyzing the cement and the consolidated sediments. Bulk samples were collected from three consecutive beaches located at the West part of Akrotiri Peninsula (Cyprus island). The samples were examined under polarizing microscope for the determination of the cement (HMC as micritic and sparitic crystals), its characteristics (isopachous bladed coating, formation of meniscus etc) and the participation of well-preserved fossil fragments. The mineralogical analysis, with the use of XRD analyzer, indicated a variety of minerals which consisting the beachrock (quartz, carbonates, plagioclase, olivine, biotite, zircon etc). Using SEM-EDS it was possible to accurately determine the cement composition and to observe its crystal characteristics. The cement agent was mainly consisted by High-Magnesian Calcite (HMC) of different crystal sizes and matrix material was present as secondary pores filling. The three studied beachrocks at the west of Akrotiri peninsula, were formed in the middle-low intertidal zone. Evidence of continuous uplift of the beachrock is observed both from geomorphological analysis and through its infrastructure. The beachrocks were highly affected by the nearby Kouris river, which supplied the material derived from the inner Cyprus areas rich in Mg2+ rocks (eg. ophiolites) and Ca2+ (eg. limestones, marbles).

Cyprus has a long record of tsunami waves, as noted by archaeological and geological records. Large boulder deposits have been noted in southeastern and western part of the Island. In the area of Cape Greco (southeastern Cyprus) large boulders have been noted, however, no detailed geomorphological research exists so far and the related high energy event remains undated. In this context, we focused at Cape Greco Peninsula at the southeastern coast of Cyprus, in order to record in detail large boulders deposits. The accumulation of the boulders along the uplifted coastline (3m amsl) was recorded. The boulders are fragments of a layer of an upper Pleistocene aeolianite, which is overlaying unconformly a lower Pleistocene calcarenite. Dimensions and spatial distribution of 272 small, medium and large boulders were documented. The precise distance of the boulders deposition from the coastline was recorded by field measurements and remote sensing with the use of GNSS, Drone mapping and GIS technics. Several large boulders weighting more than ~30 metric tons were located up to 60m inland. Geomorphologic mapping and morphometric measurements, along with the presence of marine organisms suggests that some of the boulders were removed from their original intertidal zone and were transported inland by the force of large waves. Samples of Vermetus sp. were collected from the displaced boulders in order to date the extreme event. In this work, we report and compare preliminary results from the application of widely accepted hydrodynamic equations, in order to determine the extreme event that caused their transport inland. We further attempt a correlation of the event with already known tsunami events from Eastern Mediterranean, based on the estimated wave heights and the radiocarbon dating of marine gastropods (Vermetus sp.).

In order to study the geomorphological and environmental characteristics of St. George bay, western Naxos, Greece (Fig.1), a series of 14 beachrock samples were collected and examined. Two transections of the bay, based on field measurements, were designed, in order to provide a deeper understanding of the beachrock development setting. Detailed recording of the beachrocks was accomplished through scuba diving, using a sonar device, measuring tapes, GPS device and Dive Computer. Special attention was given to the cement, as to extract information about the conditions of formation of the beachrocks. Thin sections from the beachrock samples were studied through petrographic microscope in order to investigate their basic characteristics and to obtain information about their basic petrographic and mineral composition. Scanning Electron Microscopy (SEM) alongside with Energy Dispersive Spetrometry (EDS) were used for elemental analysis of the beachrock samples and their cement and Raman spectroscopy was used for identification of the cement crystal structure. For better interpretation of the results, the suggested tool, by Mauz et al. (2015), for reconstructing relative sea level in the far-field was used. In order to estimate the  ecological status of the bay, a study of the macroalgae of the area was also accomplished. Macroalgae sampling of two different methods was conducted, destructive (conventional samples) and non-destructive (photographic samples). 57 conventional samples were collected throughout the beachrock reef. These samples were prepared into herbariums and were identified in the best taxonomic level possible using stereoscope and microscope. Photographic samples were taken from the southwestern and northeastern part of St. George bay, from different types of bedrock (beachrocks, granodiorite, aeolianite) for comparison reasons. The percentages of different types of surface coverage (algal, sediment coverage) were counted for each sample, using the program Adobe Photoshop CS6. Finally, a statistical analysis of the data from the photographic samples was conducted, using the program PRIMER 5, in order to have a better evaluation of the algae data. The depth and coordinates of each conventional and photographic sample were recorded. The results regarding the beach rock samples indicate that their formation took place under meteoric and marine vadose zone conditions. Certain results indicate that the development of the beachrocks took place during a sea level rise. Finally, macroalgae statistical analyses indicated that there are no significant differences between beachrocks and other rocks as substrates and the overall ecological status of St. George bay can be characterized as good, according to the Ecological Evaluation Index (EEI, Orfanidis et al., 2003).

Beachrocks are a window in the past environmental, geological, sedimentological and geographical conditions that were dominant on the coastal zone. The minerochemical examination of cement and the sedimentological analysis are the most efficient methods for understanding the formation mechanism. However, the examination of beachrock samples have limitations and the evidence of formation mechanism are not enough. This study emphasizes on the beachrock formation mechanism through the comparison of cement characteristics, mineral chemistry and sedimentology of beachrock occurrences from different geological and geographical setting areas Diolkos, Corinth, Greece and Sumuide, Okinawa, Japan. Furthermore, in order to investigate the beachrock formation, artificial beachrock samples were created in-vitro using sand samples and ureolytic bacteria from Okinawa under accelerating conditions. Bulk samples were collected from the study areas in order to analyze their mineralogical (XRD and SEM-EDS) and chemical (XRF) composition. Microscopy studies (optical and SEM-EDS) revealed that the cement agent from Diolkos is mainly composed of High-Magnesian Calcite (HMC) in comparison to the Sumuide beachrock which is characterized by the presence of calcite and aragonite. Additionally, the analysis revealed clastic silicate and aluminosilicate minerals. The grain composition of Diolkos slab consists of quartz, plagioclase, K-feldspar with 20% bioclasts compared to the Sumuide beachrock grains that consist of calcareous residuals from the local coral reef. The artificial beachrock investigation indicated that ureolytic bacteria that reside in the Sumuide beach sediment, are capable to precipitate aragonite coating the sediment grains and filing the pores. The cementation was most active in the top part of the samples than the bottom part. This is an indicator that the beachrock formation might occur in depths were these bacteria can be found. The artificial beachrock analysis included its physicochemical parameters using UCS penetration, pH and Ca2+ measurements, X-Ray CT-scanning, petro-graphic polarized microscopy, XRD, and SEM-EDS.

Sedimentological and geomorphological features of Mylopotas and Manganari beaches in Ios Island are investigated in order to determine seasonal changes in the texture of coastal sediments and shoreline position caused by both natural processes and human activities. The fieldwork was conducted in April 2018 and September 2018 including mapping of beach morphology in seasonal scale through topographic monitoring of shoreline, coastline and fixed cross sections in the sites under investigation using a differential GPS. In addition, sediment sampling was carried out along selected cross sections in beaches of Mylopotas (three) and Manganari (two). Grain size analysis and statistical processing were realized to reveal spatial and temporal changes of sediment parameters, such as sorting, skewness, mean and kurtosis. The results indicate a rather homogenous grain size distribution at each study area, with the majority of samples being classified as slightly gravelly sand. DGPS measurements of shoreline position in Manganari Beach indicate changes that vary between 2.50 m and 4.70 m, with the maximum displacement to be observed in the southern part of the beach, where the shoreline is retreated during spring period. Seasonal variations of shoreline position in Mylopotas Beach are up to 4.50 m with the shoreline to be advanced during spring period in the southern and northern part of the beach, while the minimum changes are measured in the central part, where a beachrock formation occurs. Occasional human interferences, such as small-scale beach restoration and nourishment projects, installation of leisure facilities and reshaping of sand dunes, conducted mainly during spring period, alter the coastal sediment budget and transport reinforcing shoreline retreat.

Sea level indicators, such as tidal notches and beachrocks, may provide valuable information for the relative sea level (RSL) changes of an area. The study area, Okinawa, belongs to the Ryukyu Islands, Japan (Pacific Ocean), forming the emerged part of an active island arc, where the Philippine Sea plate is subducting beneath the Asian continent. Evidence of emergence has been noted by various studies. Beachrocks have also been studied, however, detailed examinations of their spatial extent and cement characteristics has not been accomplished. The purpose of this study is to discuss the RSL evolution in Okinawa through the re-evaluation of reported sea level indicators, with additional observations of beachrocks and notches and RSL predictions. Our findings suggest that the majority of Okinawa beachrocks have formed in the intertidal zone. Although the vertical uncertainty of the produced SLIPs is relatively large, there is a good agreement between the different types of sea level indicators. Comparisons with RSL predictions as well as the presence of uplifted notches further suggest that Okinawa island is generally characterized by an uplift trend, which is larger in its southern part.

Coastal erosion is becoming a significant problem in Greece, Bangladesh, and globally. For the prevention and minimization of damage from coastal erosion, combinations of various structures have been used conventionally. However, most of these methods are expensive. Therefore, creating artificial beachrock using local ureolytic bacteria and the MICP (Microbially Induced Carbonate Precipitation) method can be an alternative for coastal erosion protection, as it is a sustainable and eco-friendly biological ground improvement technique. Most research on MICP has been confined to land ureolytic bacteria and limited attention has been paid to coastal ureolytic bacteria for the measurement of urease activity. Subsequently, their various environmental effects have not been investigated. Therefore, for the successful application of MICP to coastal erosion protection, the type of bacteria, bacterial cell concentration, reaction temperature, cell culture duration, carbonate precipitation trend, pH of the media that controls the activity of the urease enzyme, etc., are evaluated. In this study, the effects of temperature, pH, and culture duration, as well as the trend in carbonate precipitation of coastal ureolytic bacteria isolated from two coastal regions in Greece and Bangladesh, were evaluated. The results showed that urease activity of coastal ureolytic bacteria species relies on some environmental parameters that are very important for successful sand solidification. In future, we aim to apply these findings towards the creation of artificial beachrock in combination with a geotextile tube for coastal erosion protection in Mediterranean countries, Bangladesh, and globally, for bio-mediated soil improvement.

In recent years, traditional material for coastal erosion protection has become very expensive and not sustainable and eco-friendly for the long term. As an alternative countermeasure, this study focused on a sustainable biological ground improvement technique that can be utilized as an option for improving the mechanical and geotechnical engineering properties of soil by the microbially induced carbonate precipitation (MICP) technique considering native ureolytic bacteria. To protect coastal erosion, an innovative and sustainable strategy was proposed in this study by means of combing geotube and the MICP method. For a successful sand solidification, the urease activity, environmental factors, urease distribution, and calcite precipitation trend, among others, have been investigated using the isolated native strains. Our results revealed that urease activity of the identified strains denoted as G1 (Micrococcus sp.), G2 (Pseudoalteromonas sp.), and G3 (Virgibacillus sp.) relied on environment-specific parameters and, additionally, urease was not discharged in the culture solution but would discharge in and/or on the bacterial cell, and the fluid of the cells showed urease activity. Moreover, we successfully obtained solidified sand bearing UCS (Unconfined Compressive Strength) up to 1.8 MPa. We also proposed a novel sustainable approach for field implementation in a combination of geotube and MICP for coastal erosion protection that is cheaper, energy-saving, eco-friendly, and sustainable for Mediterranean countries, as well as for bio-mediated soil improvement.

Floods are among the most dangerous natural hazards affecting the development of an area. In Greece, many drainage basins are relatively small with steep slopes, configured by steep streams with braided main channel morphology. These systems are usually dry, but experience extreme flash flood events of low frequency, but high magnitude. Such exceptionally high runoff may be a source of significant damage to human infrastructure. Despite the importance of these floods, the hydrological analysis of ephemeral streams in Greece has been especially difficult due to the lack of discharge gauges.The aim of this study is to present a flood hazard assessment and mapping methodology for the Kerinitis River drainage basin which is located in the North Peloponnese. Additionally, the simulation of a flash flood event along the main channel of the river caused by an extreme rainfall event, similar to the storm that took place on January 11th and 12th, 1997 above the nearby catchment of Xerias River, using a surface GIS-based runoff model was attempted. The application of this modeling led to the direct runoff hydrograph along the Kerinitis main channel at the outlet of the basin (the apex of the fan-delta). The proposed methodologies are based on the application of GIS with the integration of various data concerning the study area.

Akrotiri Salt Lake is located 5km west of the city of Lemesos, in the southern-most part of the island of Cyprus. The palaeogeographic evolution of the Akrotiri Salt Lake presents a great scientific interest, especially during the Holocene where the eustatic movements combined with local active tectonics and climate changes have developed a unique geomorphological environment. The Salt Lake, today a closed lagoon, which is depicted in Venetian maps (Bordon AD 1528) as being connected to the sea, can provide evidence of the geological settings and landscape evolution of the area. In this study, we investigate the development of Akrotiri Salt Lake through a series of cores which penetrated the Holocene sediment sequence. Sedimentological, micropaleontological (benthic foraminifera and ostracods) analyses and geochronological studies performed on deposited sediments, identifying the complexity of the evolution of the Salt Lake and the progressive change of the area from maritime space to an open bay and finally to a closed Salt Lake.

Platis Gialos Bay located at the Southern part of Sifnos Isl. and his length is determined at 1.000 m, with SE direction. The coast of Platis Gialos Sifnos has been under erosion and permanent coastal retreat for several years, especially at the central and west part of the beach. The main causes of coastal erosion are anthropogenic.This paper focuses most intently on the geomorphological and sedimentological dynamic processes of the Bay which forming the current situation. For this reason a number of tasks took place in order to determine the level of disturbances of this dynamic equilibrium. This study included two phases of survey for two different periods (summer/winter). The first phase deals with the geomorphological and sedimentological coast characteristics, and includes: i) long-term geomorphological evolution of the coastal zone through the analysis of satellite images (Google Earth), in order to estimate the intensity of coastal erosion. ii) topographic sections at the surface of the coastal zone, through D-GPS (Spectra Precision SP80 GNSS Receiver), perpendicular to the coastline, iii) sediment sampling in the subaerial coastal area, iv) analytical recording and mapping of the summer and winter shorelines via the D-GPS, v) the situation of the potential feeders of the shore with materials, necessary for the formation of an alluvial beach, and vi) recording of land uses (Fig.1). The second phase, includes the geomorphological and sedimentological characteristics of the marine area, in particular: i) topographic sections of the bottom surface until the depth of 1.5 m, through D-GPS, perpendicular to the coastline ii)sediment sampling in the subaquatic marine area, iii) data of the numerical recomposition of the wind and wave conditions of the study area, iv) bathymetric eco-sonar data (Lowrance LCX-15MT), v) side-scan single beam eco-sounder (StarFish 450), to determine the seabed morphological features of the bay and, vi) substrate component mapping (Fig. 1). Laboratory analyzes were followed by the methods of dry granulometry, in order to categorize it, in different types on the basis of Folk & Ward (1957) method through GRATISTAT (v.8) software.

In this paper, we focus on the southeastern coastal zone of the island of Samos (east-central Aegean Sea), in order to reconstruct the evolution of coastal landscapes and the relative sea-level changes during the late Holocene. We use geomorphological mapping, sedimentological and palaeontological proxies of late Holocene coastal deposits from two lagoon environments. We further compare our results with previously published sea-level data and we show that the southeastern part of Samos was characterized by a subsidence trend at least during the late Holocene, with RSL rise rates of ∼0.8 mm/yr. Our study additionally highlights that local-scale tectonics is responsible for the evolution of the coastal zone of Samos.

Beachrocks are consolidated sedimentary formations and are composed of coastal sediments, which are cemented through the precipitation of carbonates. The lithification takes place in the intertidal zone and can include various sediments, such as sands and gravels of clastic and biogenic origin. This study deals with the cements’ mineralogical and geochemical features of a beachrock outcrop and its aim is the contribution for further understanding on the cementation process of beachrocks. (e.g. Vieira and Ros, 2007; Vousdoukas et al., 2007; Karkani et al., 2017).

Akrotiri Salt Lake is located 5km west of the city of Lemesos, in the southern-most part of the island of Cyprus. The palaeogeographic evolution of the Akrotiri Salt Lake presents a great scientific interest, especially during the Holocene where the eustatic movements combined with local active tectonics and climate changes have developed a unique geomorphological environment. The Salt Lake, today a closed lagoon, which is depicted in Venetian maps (Bordon AD 1528) as being connected to the sea, can provide evidence of the geological settings and landscape evolution of the area. In this study, we investigate the development of Akrotiri Salt Lake through a series of cores which penetrated the Holocene sediment sequence. Sedimentological, micropaleontological (benthic foraminifera and ostracods) analyses and geochronological studies performed on deposited sediments, identifying the complexity of the evolution of the Salt Lake and the progressive change of the area from maritime space to an open bay and finally to a closed Salt Lake.

In order to investigate the formation processes of the seafloor of Argostoli bay (Cephalonia Island, Ionian Sea), an extended geological survey was conducted to gather details about the near-surface geological framework. Methods used for the survey include high resolution subbottom seismic profiles (29.4 line kilometers; EdgetechCHIRP system at frequencies 2-16 kHz) side-scan sonar backscatter surveys of the seafloor (approximately 67 line-km, Starfish 450F), single-beam bathymetry (approx. 67 line-km, Lowrance LCX-15MT Sonar system), and bottom sampling including bottom sediment grab samples (van veen grab sampler) and short sediment cores. The survey was focused at both ends of Argostoli Bay (i.e., Argostoli and Livadi inlets). Preliminary analysis of the sub-bottom profiles in the upper 12-20 m reveals a clear pattern of sediment layers, in both ends of the bay. The uppermost layers been deposited horizontally with small differences in their orientation in the area of Argostoli inlet, while the presence of gas is more pronounced in Livadi inlet. Moreover, in Argostoli inlet a palaeo-surface is visible (probably the base of Holocene sedimentary cover) with minor channel features, likely indicating a shallow river valley. Side- scan mapping in combination with sediment samples and cores showed that the surface sediment consists mostly of finegained material, rich in organic matter over a gravel-lag deposit that may represent the transgressive surface in the area.

This study focuses on the sedimentological and morphological features of Vravrona Beach, East Attica, in order to determine the seasonal changes in the textural group classification of the costal sediments, as well as, changes in coastline position (Fig. 1). Additionally, Vravrona Beach has been chosen for the assessment of a potential coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the broader area of East Attica (Dimou et al., 2010). For the composition of the beach profile in seasonal scale, cross sections were conducted along the beach from landward to seaward until approximately 10 m from the coastline. Beach width as well as the current coastline position for each season were measured with a differential GPS (DGPS). The land use at the landward upper limits of the study area were also measured. Along selected cross sections, sediment sampling was also conducted during January 2018 for the composition of the winter profile of the study area and during September 2018 for the composition of the summer profile of the study area. Sedimentological analyses were based on grain size distribution for the analysis of unconsolidated sediments by sieving and statistical parameters such as sorting, skewness, mean and kurtosis were calculating using GRADISTAT v. 0.4 software in order to determine the sedimentological features of the study area and the transport mechanism at the time of deposition. The textural group of the samples was also determined by Folk and Ward (1957) classification. The grain size analysis of the samples, collected between the upper limit of the beach and the coastline during summer period, show that the majority of grains is described as slightly gravelly sand and gravelly sand, but during the winter period the grains are between gravely sand and sand. The samples collected from the coastline until approximately 10 m seaward are mainly described as slightly gravelly sand and sandy gravel for both sampling seasons (Fig. 2). DGPS measurements of coastline position indicate changes that varies between 4.38 m to 7.41 m with a maximum value at 8.27 m. In agreement to field observations, DGPS measurements indicate an accumulation of sediments at the northern part of the beach during the winter period, while during summer period there is an accumulation of sediments at the southern part of the beach.

The west coast of Naxos Isl. was hit in 1956 by the Amorgos tsunami. This study aims to: a) determine the impact of a potential tsunami similar to the one that occured in 1956, based on the island's contemporary residential and tourist development, and b) explore whether the natural geomorphs (sand dunes) in the 3 study areas (Glyfada, Agios Prokopios, Chora of Naxos) can reduce the tsunami risk. Risk assessment was based on processing field data (differential GPS) and satellite images with GIS software. Furthermore, the dunes potential risk reduction has been evaluated. Results show that taller sand dunes and vegetation provides better tsunami protection to the coast of Glyfada, than the one of Agios Prokopios. Uncontrolled tourism development without any sand dunes protection measures underline their development and, consequently, increases the tsunami risk.

Archaeological remains are valuable relative sea-level (RSL) indicators in Israel, a tectonically stable coast with minor isostatic inputs. Previous research has used archaeological indicators to argue for centennial sea-level fluctuations. Here, we place archaeological indicators in a quality-controlled dataset where all indicators have consistently calculated vertical and chronological uncertainties, and we subject the data to statistical analysis. We combine the archaeological data with bio-construction data from Dendropoma petraeum colonial vermetids. The final dataset consists of 99 relative sea-level index points and 12 limiting points from the last 4000 a. The temporal distribution of the index points is uneven; Israel has only four index points before 2000 a BP. We apply an Errors-In-Variables Integrated Gaussian Process (EIV IGP) to the index points to model the evolution of RSL. Results show RSL in Israel rose from −0.8 ± 0.5 m at ∼2750 a BP (Iron Age) to 0.0 ± 0.1 m by ∼1850 a BP (Roman period) at 0.8 mm/a, and continued rising to 0.1 ± 0.1 m until ∼1600 a BP (Byzantine Period). RSL then fell to −0.3 ± 0.1 m by 0.5 mm/a until ∼650 a BP (Late Arab period), before returning to present levels at a rate of 0.4 mm/a. The re-assessed Israeli record supports centennial-scale RSL fluctuations during the last 3000 a BP, although the magnitude of the RSL fall during the last 2000 a BP is 50% less. The new Israel RSL record demonstrates correspondence with regional climate proxies. This quality-controlled Israeli RSL dataset can serve as a reference for comparisons with other sea-level records from the Eastern Mediterranean.

Different types of sea-level markers have been used in the Eastern Mediterranean in order to assess Late Quaternary coastal evolution and relative sea-level (RSL) changes. RSL reconstructions are useful for various researches, ranging from the investigation of crustal movements to the calibration of earth rheology models and ice sheet reconstructions. GIA models have often been employed to identify stableand unstable areas and deduce tectonic rates through comparisons with observational data. It is generally assumed that most Cycladic islands (Aegean Sea, Greece) are affected by a gradual subsidence, ascribed to the thinning of the local earth crust and to isostatic processes that accompanied the post-glacial rise in sea level. The absence of morphological coastal features indicative of uplift, such as marine terraces or benches, elevated beachrocks, marine notches, or raised Quaternary coastal deposits, are often interpreted as an absence of local uplift.Although Paros Island presents great interest in terms of geoarchaeology, the evolution of its shoreline and RSL changes have not been studied in detail. The Island lies in the center of the Aegean Sea, in central Cyclades. In order to elucidate the RSL changes in the area and place an improved chronological constrain for the Late Holocene, we present new RSL index points, derived from sediment cores fromParos Island in combination with published geomorphological and sedimentological data from Paros and Naxos Island. Our results are further compared with sea-level predictions from two different GIA models in an attempt to better quantify the tectonic regime of the wider study area.

In this paper we attempt to classify drainage sub-basins according to their erosion risk. We have adopted a multi-step procedure to face this problem. The input variables were introduced into a GIS platform. These variables are the vulnerability of the surface rocks to erosion, slope gradient, vegetation cover and land use and drainage basin characteristics. We then constructed a fuzzy inference mechanism to pre-process the input variables. Next we used neural-network technology to process the input variables. The above system was trained to ‘learn’and classify the input data. The output of this procedure was a classification of the sub-drainage basins related to their risk of erosion. This neuro-fuzzy system was applied to the island of Lefkas (Greece).

This research applies the fuzzy set theory via Geographical Information Systems (GIS) - based analysis to investigate slope erosion by water. The main steps of thisprocedure are the definition of the input variables (rocks’ susceptibility to erosion, slope angle, slope morphology), the development of a fuzzy inference system based on theoretical and empirical knowledge, transforming the input to output variables(erosion – deposition) and the visualization of the output variables (spatial distribution of the erosion-deposition processes). The method was applied at the Corinth drainage basin, located in the north-eastern part of Peloponnese (Greece),where a series of catastrophic erosional events have recently occurred.

This research deals with the flood risk in the island of Naxos (Cyclades, Greece). In the stream called Peritsi or Paratrexos, the geomorphology, geology, the land uses and the relief of its drainage basin were studied in detail. These results allowed the estimation of flood risk in the area of Naxos, as well as the security measures that need to be applied. The main aim is the investigation between the relation of rainfall and the outflow with the use of hydrographs. Thus an evaluation of the flood risk of this basin has been studied. In order to produce results of high accuracy the basin was divided into 13 smaller sub-basins which were interpreted separately. For the optimum application of method Clark, there were two tools used: a) water level recorder, b) Meteorological station. Based on the processes mentioned above, individual hydrographs were produced for each of the 13 sub-basins. Once again, the main goal of this project is to compare the rain and outflow parameters in order to identify the areas of the highest risk. Additionally, a flood map has been developed which visualizes the risk scale in a color coded image.

There is a wide range of alternative approaches to study erosion processes. In this paper the construction of a model based in the interaction of Geographical Information System (GIS) and Artificial Neural Networks (ANN) is described. Theneural model uses supervised competitive learning process. The whole procedure starts with the digitization of collected data and the definition of the input variables, such as slope form and gradient, susceptibility to erosion and protective cover. The input variables are transformed into the erosion risk output variable using the neural model. The last stage concerns the development of an erosion risk zones map.

The littoral region of Alexandria, east of Silsileh (the eastern promontory of the Eastern Harbor) to Montazah promontory was investigated combining archaeological and geomorphological evidence in order to better understand the subsidence of the coastal zone. The coastal zone is rich in archaeological and geomorphological features able to provide insights into the evolution of the coastline and the relative sea level changes. Our study has revealed a continuous subsidence of the coastal zone, owed to various contributing processes, while further research is required to decipher the coastal evolution of this littoral.

Fluvial geomorphology is affected by physical conditions which allow its adaptation due to high dynamics and environmental influences. Fluvial morphological changes are manifested as a result of tendency of the river system to maintain its physical balance. Our study area is the upper and middle flow part of Vouraikos river and surrounding area, near the NW border of Chelmos mountain in Northern Peloponnese, near the town of Kalavrita, at an altitude of 800 m. The area is part of the Skepasto basin, constituting of a graben with a general E-W direction that was developed NW of Kalavrita. The area comprises of Mesozoic, Upper Triassic-Jurassic limestone and dolomite of the Tripolitsa unit External Hellenides and Plio-Pleistocene fluvio-lacustrine sequences, while its tectonic structure is characterized mainly by normal faults. The geomorphological landscape is characterized by alluvial deposits and important geomorphological features including fluvial terraces, alluvial fans, fluvial scarps and their main rill washes. This area has been a place of major human activity as shown by the findings of many uncovered artifacts and a settlement. Through a paleographic reconstruction, detailed field investigations, in combination with the compilation of geomorphological maps using GIS software and archaeological evidence found in the area, we attempted to reconstruct the fluvial evolution of Vouraikos river and identify the major geomorphological factors that led to, and influenced it. Finally, the link between cultural activities and sedimentary processes is also studied. The recorded environmental variations had a great impact on the geomorphological shaping and instability of Kalavrita plain and Vouraikos river and are being reflected on the buried settlement. Sediment fluxes were high enough to form strath terraces, while local tectonics aided in the strath and fill terrace creation. Smaller and younger strath terraces, formed during increased sediment supply periods, when the valley was at a higher level.

Although there is rich evidence for human occupation of Paros’ coastline, there is a dearth of data with regards to the evolution of the island's seaboard palaeoenvironments. In this paper, we use sedimentological and palaeontological proxies of late Holocene coastal deposits from lagoonal environment to reconstruct the evolution of coastal landscapes in Paroikia Bay (Paros Island, Greece). A semi-enclosed lagoon existed in the northeastern part of Paroikia from at least 2915–2551 BC, which was gradually infilled after around 780–436 BC. Although it was not possible to chronologically constrain the timing of the infill, it is most likely relatively young, indicating anthropogenic effects. A correlation of our chronostratigraphic data with archaeological remains and tidal notches in the study area suggests that the subsidence observed on Paros Island is linked to long-term subsidence in combination with vertical seismic displacements.

Two well-developed quaternary sand dune fields have been identified on the western and eastern side of Akrotiri promontory (Lemesos, Cyprus, Mediterranean Sea). The fields extend immediately from the low level of their source beaches onto higher ground (> 38m amsl).  Geomorphic observation supported by OSL dating of multimineral sand horizons demonstrate several phases of sand accumulation in the western field in contrast to the smaller eastern system, where the evidence direct to a relatively recent dune emplacement. The effects of climatic change, relative sea-level change and anthropogenic influence in dune evolution, have been evaluated in both sites in combination with documented evidence of human induced destabilization of the western sand dune field during the 1970s and 1980s. Both fields share similar topographic settings and situated in close proximity but they do not share an entirely similar evolution history. The observations and the data suggest the combination of local and regional control of the development of the sand dunes and the geochronological analysis with luminescence methodology support the ability of the method to reconstruct the evolution of sand dunes fields in the south eastern Mediterranean area.

Sea level indicators, such as tidal notches and beachrocks, may provide valuable information for the relative sea level (RSL) changes of an area. Although beachrocks have received various arguments regarding their accuracy as sea level indicators, they have often been used to assess Holocene shoreline changes and crustally induced RSL changes. The study area, Okinawa, belongs to the Ryukyu Islands, Japan (Pacific Ocean), forming the emerged part of an active island arc, where the Philippine Sea plate is subducting beneath the Asian continent. Various studies have noted evidence of emergence. Beachrocks have also been studied, however, detailed examinations of their spatial extend and cement characteristics has not been accomplished. In this context, the aim of this research is to discuss the RSL evolution in Okinawa through the re-evaluation of reported sea level indicators, along with additional observations on beachrocks and notches. Fieldwork was accomplished in the coastal zone of Okinawa, through detailed spatial mapping and sampling of beachrock occurrences. Coastal transects were accomplished in order to measure the width and depth/elevation of beachrock slabs. In order to perform petrographic analysis, stained thin sections were studied using transmitted light microscope where selected samples were studied under SEM.

Akrotiri peninsula is located 5km W of the city of Lemesos and is the southernmost part of the island of Cyprus. Akrotiri peninsula consists of Quaternary sediments which are unconformably deposited on Miocene Pachna formation (chalks and marls). The Quaternary sediments include marine and associated aeolian deposits, alluvial fans and lagoonal and deltaic sediments.  Quaternary marine deposits occur as raised marine terraces with arenitic composition and they are located between elevations of 2-3m and 16-18m amsl. Quaternary alluvial fans were formed by material from the Kouris River, the largest river in Cyprus, and contributed to the formation of a western tombolo, resulting in a bay in antiquity. Local tectonics and eustatic changes resulted in the creation of Holocene geomorphological features, predominately, a salt lake, with an average water table of about 2 m below MSL, which is surrounded by uplifted marine terraces and lagoonal sediments. Based on geomorphologic mapping of the Quaternary landforms and associated deposits, and the morphosedimentary analysis of the geomorphological features, a chronostratigraphic framework for the Holocene evolution of the area has been generated. Textual references of Akrotiri peninsula first appear in Roman time by geographer Strabo who is describing it as a peninsula – like place. In Venetian and Ottoman maps is depicted the evolution of the area, the formation of the eastern tombolo and the usage of the closed lake as a fishery. Also, the diversion of Kouris River by Saint John’s knights west of the village of Kolossi, assisted the production of Sugar Cane and influenced the topography of the area.

This work focuses on the beachrocks of Paros and Naxos Islands, in central Cyclades, Aegean Sea, Greece, in an attempt to study their geochemistry and interpret their palaeoenvironmental significance. Beachrocks are coastal sedimentary formations, consisting of beach sediments that are relatively quickly cemented through the precipitation of CaCO3. However, debate still exists concerning their depositional environment, and therefore, their use as indicators for sea-level changes.In this study we focus on the beachrocks of Paros and Naxos islands, which are found at various depths. For the aim of the present study, representative bulk samples from both islands were analyzed for their mineralogical (XRD and SEM) and chemical (XRF) composition. The cement agent and the fine sand/clay fraction of the samples mainly consist of authigenic magnesian calcite, which commonly precipitates in shallow marine environments, especially in high concentration of Ca2+(>4 mol% CaCO3 or 1.2 wt.%). Furthermore, a series of clastic silicate and alumino-silicate minerals are detected. The predominant coarse fragments hosted within the cement material are quartz, plagioclase and K-feldspar.The texture of the beachrock samples varies from almost homogeneous sandstone to a mixture of lithologies, such as massive gravel, sandstone and claystone. Most of the grains are flattened and only rarely angular pieces of siliceous rocks occur, hosted in the fine-grained Mg-calcite cement. This grain size and shape is indicative of the genetic environment of beachrocks, implying the maturity level of cementation from early stage to modern situation.The beachrock samples derived from various depositional periods and depths, from the front and end slabs. The beachrocks were also correlated with stratigraphical material from boreholes and archaeological remains from the study area in an attempt to understand the coastal changes during the late Holocene in Central Cyclades.

This research was conducted to determine the geomorphological and sedimentological characteristics of the shallow sea bottom (water depth <25 m) of Chania Bay. A detailed bathymetric survey was held from the coastline to the isobath of 25 m. Also was held an overview scanning of the sea bottom by the Side Scan Sonar to record the landforms and the structures of it. Sampling was carried out both to surface sediments and to rocky bottom, in order to study the grain size and the mineralogical composition of loose deposits, and the petrographic features of the hard substrates.The study area is the Chania Bay, which is located in the western and northern part of Crete Island and extents from the area of Kato Stalos, to the east, to the village of Kolimbari, in the west.For the integrated approach and interpretation of the results of this work, we study the effect of topography, geology and hydrology of the basin to the coastal system of Chania Bay. In addition, we investigate the wind and wave status in the region which forms the morphodynamics characteristics of the coastal zone.The ultimate purpose of this work is to link the gained knowledge with the European Union Guidelines on Integrated Coastal Zone Management and the Marine Strategy as well as the implementation of the rules on Maritime Spatial Planning. Based on this integrated maritime policy, the EU aims at the economic and social development of areas related to the marine environment in the context of its friendly use. But especially through marine spatial planning and in combination with increased knowledge of the marine environment, we are able to secure financial investment and improve the way we manage the marine and terrestrial space, while preserving the ecosystem of the area in sustainable conditions

Although there is rich evidence for human occupation of Paros’ coastline, there is a lack of data regarding the evolution of the island’s coastal palaeoenvironments. Paros Island is part of the Cyclades Islands complex, in the central Aegean Sea. It is the third largest island of the Cyclades. The Island is of great geoarchaeological significance, with the earliest evidence of occupation dating back around the 5th millennium BC, while the nearby island of Saliagos has yielded a Neolithic settlement. The studied site, Livadia, is located in the northwestern part of Paros Island, near the modern capital, Paroikia.For the purposes of this work, a multiproxy analysis was undertaken, which included sedimentological and biostratigraphic analyses of Late Holocene coastal deposits from lagoonal environment, aiming to reconstruct the evolution of coastal landscapes in Paroikia Bay (Paros Island, Greece). In order provide insights into the coastal evolution and the RSL changes of this sector of the Aegean, the dated samples of this study were compared with already published archaeological data, geomorphological sea level indicators and with the RSL curve derived from the glacio-hydro-isostatic model for the region.

The paper starts recalling the various stages that lead to the definition of the Early Byzantine Tectonic Paroxysm (EBTP), which was determined mainly from fossil uplifted shorelines of the Eastern Mediterranean between the middle of the 4th century and the middle of the 6th century CE. A comparison of catalogues of earthquakes may show that possibly an important event occurred in 361 CE in the northern Adriatic, i.e. near the beginning of a sequence of clustered earth movements. This event is proposed as the most likely for the coseismic subsidence of a known slightly submerged tidal notch that developed along over 200 km of the Croatian shoreline.

A coastal and submarine geomorphological investigation took place in the coasts of eastern Attica, aiming to identify palaeoshorelines. Former sea-level positions were deduced from emerged and submerged tidal notches. Eight fossil shorelines were deduced in the study area; two emerged ones at about +24 ± 30 and +40 ± 30 cm, and six submerged ones at about −22 ± 30 (modern), −40 ± 30, −60 ± 30, −80 ± 30, −130 ± 30 and −460 ± 30 cm. It is worth mentioning that a rather different tectonic behavior may be distinguished between the south (AT1-AT5) and the north (AT10-AT28) part of the study area.

In this paper the tectonic behavior of Leukas and Meganisi islands (Ionian Sea) is examined through underwater research carried out in both islands. A possible Late Holocene correlation between coseismic subsidences is attempted and evidenced by submerged tidal notches in both islands. These subsidence events probably occurred after the uplift that affected the northernmost part of Leukas around 4 to 5ka BP. In conclusion, although the whole area was affected by a similar tectonic strain, certain coseismic events were only recorded in one of the two islands and in some cases they affected only part of the study area.

Beachrocks represent a significant paleo-environmental proxy because they can record both the vertical and the horizontal evolution of the shoreline. They have often been used to assess Holocene shoreline evolution and crustally induced Relative Sea-Level (RSL) changes in the Mediterranean Sea. In this paper, we used submerged beachrocks from Paros and Naxos Islands (Aegean Sea, Greece) to reconstruct the shoreline modification and provide new insights on the RSL evolution in central Cyclades. Paros and Naxos Islands are of great importance in terms of archaeological evidence of coastal occupation. However, the evolution of their coastlines was seldom explored. In this study, we coupled detailed underwater surveys, analysis of aerial photogrammetry, microstratigraphic analysis and luminescence dating to study beachrock outcrops found down to about 6 m below the present sea-level. We, then, spatially and chronologically constrained some major palaeogeographical changes of a number of coastal sectors of the two islands. Furthermore, the multiple analyses of beachrocks, sediment coring and archaeological data suggested that RSL rose by at least 3.8 m in the last 4.0 ka and that RSL variation in the last 2.0 ka did not exceed 2 m with respect to the present mean sea level.

The littoral region of Alexandria, east of Silsileh (the eastern promontory of the Eastern Harbor) to Montazah promontory was investigated combining archaeological and geomorphological evidence in order to better understand the subsidence of the coastal zone. The coastal zone is rich in archaeological and geomorphological features able to provide insights into the evolution of the coastline and the relative sea level changes. Our study has revealed a continuous subsidence of the coastal zone, owed to various contributing processes, while further research is required to decipher the coastal evolution of this littoral.

The study "3,000 Years of East Mediterranean Sea Levels" investigates whether trends observed during this period in Israel from archaeological indications can be corroborated and strengthened by comparing them with relative sea levels observed in Greece. The process is comprised of three questions: 1) What types of archaeological sea-level indicators in Greece and Israel have the highest level of reliability for dating and sea-level evaluation? 2) What are the overall trends of sea-level change in Greece and Israel during the last 3,000 years, and what degree of error do these curves have? 3) What if any regional trends can be identified from the combined Greek and Israeli data? To answer the above questions, three objectives are pursued: 1) Identify archaeological RSL indicators of the last 3,000 years in Israel and Greece, including already published indicators with adequate measurements, those published but in need of new measurements, and unpublished potential indicators. 2) Assess the reliability of indicators using a consistent scoring system, correction for isostatic and tectonic effects, more precise measurements from indicators, and by exploring new methods to determine the chronology of rock carved indicators in Israel. 3) Using the assembled data, create a sea-level reconstruction for Greece, and combine the data with existing reconstructions from Israel for an analysis of matching trends. The study began with research of published sources and was supplemented by field activity. Surveys in Greece including Crete to assess both published and potential indicators occurred. Ruins from Chersonisos and Matala in Crete were examined and new measurements were taken from the latter. Fieldwork was also performed in Israel, including measurements from Caesarea for functional elevations on water channels at the promontory palace pool, at Achziv's fishpond, and around Tel Dor. The survey collected nearly 140 indicators from Israel and about 120 from Greece (excluding those outside the project's chronological scope). Of the Israeli indicators, some 120 were deemed reliable enough for reconstructions, whereas in Greece only 40 were, and not all of these from tectonically stable areas. The higher reliability of the Israeli dataset may stem from a smaller coastline and more focused sea-level research over the past few decades. In Greece, many measurements were taken by archaeologists in the 20th century before precise surveying methods were available, and published without sufficient metadata. Since then some of the sites have also become inaccessible to sea-level researchers. Analysis of indicators revealed gaps and disparities between the two regional datasets. Israel has a very strong set of many indicators from the Roman Period (~2000BP) to present, but fewer from 3000-2000BP. Greek indicators are strongly clustered in the Classical and Hellenistic Periods (2500-2000BP) with fewer before or after. These disparities make it difficult to effectively compare sea level between regions, but results suggest some correspondence of the curves. Analysis supports the work of previous Israeli researchers and suggests a relatively stable sea level there for the last 2000 years, with possible fluctuations not exceeding half a meter above or below current sea level at ~1500BP and ~750BP respectively. Both regions indicate a sea level rise between 2500-2000BP, but more data from Israel is needed to confirm this, while data from 3000-2500BP in Israel and Greece alike is scarce. In addition to the overall regional RSL comparisons, the current study also identifies the need for ongoing research and data collection: Continuing the search for sea-level indicators in Israel from 3000-2000BP, and in Greece from 3000-2500BP and from 2000BP to present, particularly in areas of reported tectonic stability like the Cyclades.

The last 3,000 years of relative sea level (RSL) in Israel are derived primarily from archaeological indicators with additional bio-construction indicators (Dendropoma petraeum reefs at the edge of the abrasion platform along the Israeli coast). The current study examines whether sea-level fluctuations (above and mainly below present-day MSL) observed along the coast of Israel can also be observed in other East Mediterranean areas like Greece so that better evaluations can be made of local and regional driving mechanisms. There are three objectives for achieving this goal: 1) Identify new and already published archaeological and biological RSL indicators from this period in Israel and Greece; 2) Assess the reliability of both existing and new indicators using consistent standards to determine which types most accurately indicate ancient RSL and with what degree of uncertainty; 3) Correct the data for isostatic and tectonic effects. The survey collected nearly 140 archaeological indicators from Israel and about 120 from Greece. Of the Israeli indicators, some 120 were deemed reliable enough for reconstructions, whereas in Greece only 40 were, and not all of these from tectonically stable areas. The Israeli data includes 31 dates obtained from Dendropoma reefs in Israel. The higher reliability of the Israeli dataset may stem from a smaller coastline and more focused SL research over the past few decades. In Greece, many measurements were taken before precise surveying methods were available, and published without sufficient metadata. The two regional datasets reveal chronological gaps and disparities: Israel has a strong set of many indicators from the Roman Period (2000BP) to present, but fewer from 3000-2000BP, while Greek indicators are strongly clustered in the Classical to Hellenistic Periods (2500-2000BP). On-going research is focusing now also on the last Millennial Greek sea levels (mainly the ‘Venetian’ period). Results however suggest some correspondence and support previous Israeli conclusions suggesting somewhat lower levels around 2500BP and in the first half of the last Millennium: The Crusader period in Israel (11th to 13th century AD) and the Venetian period in Greece (12th to 15th century AD). Near-present, stable levels are indicated during most other periods, despite indications of slightly higher sea levels in the late Roman/Byzantine period.

Beachrocks represents a coastal deposition in the intertidal area, and studying their properties may lead to create a model which identifies the conditions of their formation (paleo-environment). This paper focuses most intently on the cement material which is able to recover the paleo-environment conditions during diagenesis of such coastal sediment. We used optical microscopy, secondary electron microscopy and Raman Spectroscopy to characterize the cement texture, mineralogy and chemistry in the beachrocks. The existence of pure calcite primarily controlled by the meteorite water, while Mg-calcite appears between the lower meteoric and the upper marine phreatic zone. Finally, the presence of aragonite associated with the marine phreatic to lower marine vadose environment.

In this paper a re-analysis of previous research concerning an uplifted tidal notch developed near the modern harbor of Poros (eastern Cephalonia Island, Ionian Sea, Greece) is undertaken. According to radiocarbon dating, this notch was active between the 4th–6th century AD and 1953 AD, i.e. for at least 1450 years. Recent measurements have shown that the inward depth of the notch profile at well preserved sites is 93 cm. This permits an estimate of the average rate of intertidal bioerosion to 0.64 mm/a for this time period.

Fossil shorelines produced by recent co-seismic movements were identified through a submarine survey along the coasts of Ithaca and Fiscardo (Greece). In both areas a tidal notch-slightly submerged below present Mean Sea Level (MSL) was observed at various sites. This “modern” notch is known to have been submerged by the global sea-level rise during the 19th and 20th centuries. The depth after tide and air-pressure correction of the vertex of the “modern” notch (that owes its submergence to the current rapid sea level rise) was measured between -20 and -30±5cm at Fiscardo and between -36 and -45±6cm at Ithaca. This “modern” notch at the same depth on east and west sides of the Ionian Thrust suggests that both areas were not affected by the co-seismic vertical movements that occurred in 1953 (in the wider area). On the other hand, a greater depth in Ithaca could be an effect of co-seismic subsidence. Over the long term, the tectonic behavior of Ithaca differs from Fiscardo. At Ithaca no evidence of emergence was found and Holocene vertical movements have been only of subsidence: submerged fossil tidal notches were distinguished below MSL at about -40 (modern), -60, -75, -95, -106, -126, -150 and -220±6cm. On the East coast of Fiscardo peninsula impacts of ancient earthquakes have left some marks of emergence at about +18 and +44±5cm, and of submergence at about -25 (modern), -45, -60, -75, -82, -100 and -230cm, with even some evidence of past uplift and subsidence at the same sites.

Biophysical restoration or rehabilitation measures of land have demonstrated to be effective in many scientific projects and small-scale environmental experiments. However circumstances such as poverty, weak policies, or inefficient scientific knowledge transmission can hinder the effective upscaling of land restoration and the long term maintenance of proven sustainable use of soil and water. This may be especially worrisome in lands with harsh environmental conditions. This review covers recent efforts in landscape restoration and rehabilitation with a functional perspective aiming to simultaneously achieve ecosystem sustainability, economic efficiency, and social wellbeing. Water management and rehabilitation of ecosystem services in croplands, rangelands, forests, and coastlands are reviewed. The joint analysis of such diverse ecosystems provides a wide perspective to determine: (i) multifaceted impacts on biophysical and socio-economic factors; and (ii) elements influencing effective upscaling of sustainable land management practices. One conclusion can be highlighted: voluntary adoption is based on different pillars, i.e. external material and economic support, and spread of success information at the local scale to demonstrate the multidimensional benefits of sustainable land management. For the successful upscaling of land management, more attention must be paid to the social system from the first involvement stage, up to the long term maintenance.

Sea level indicators, such as tidal notches and beachrocks, may provide valuable information for the relative sea level changes of an area. Beachrocks in particular have received various arguments concerning their use as reliable sea level indicators and their formation environment. This work focuses on the coasts of East Attica in order to trace the palaeoshorelines of the Upper Holocene through the study of beachrocks. The coastal zone was surveyed in detail by snorkelling and diving, in order to locate, map and sample beachrocks. The samples were studied under a SEM, which showed that the beachrocks are mainly composed of quartz grains, a few calcites and feldspars, while the carbonate cement is characterized with the presence of MgO at percentages between 5 and 7.8%. Based on correlations with published drillings in the study area, the studied beachrocks should not be older than 2000 years BP.

Remains of past sea levels, such as tidal notches, benches, beachrocks, etc. may provide valuable information for the investigation of relative sea level changes of eustatic and/or tectonic origin. Tidal notches are usually formed in limestone cliffs in the mid-littoral zone, are well known as precise sea-level indicators and they can attest to the modality of sea level change (rapid or slow) allowing to identify palaeoseismic events. In this framework, this work focuses on the eastern coasts of the Attica Peninsula (eastern Greece) in order to trace the palaeoshorelines of the Upper Holocene through the use of tidal notches and discuss their implication for the interpretation of the recent tectonic history in the area. A submarine geomorphological investigation took place in the coasts of eastern Attica, aiming to identify palaeoshorelines. Former sea-level positions were deduced from emerged and submerged tidal notches. An attempt was made to date past sea level positions, based on 14C datings from sedimentological data of drillings in nearby locations for the submerged tidal notches while one uplifted shoreline was dated with 14C based on a shell collected at a nearby location. Eight fossil shorelines were deduced in the study area; two emerged ones at about +24±6 and +40±6 cm, and six submerged ones at about -22±6 (modern), -40±6, -60±6, -80±6, -130±6 and -460±6 cm. It is worth mentioning that a rather different tectonic behavior may be distinguished between the south (AT1-AT5) and the north (AT10-AT28) part of the study area.

Tidal notches are a well-known sea-level indicator, marking clearly former shorelines, which have often been used to deduce Quaternary tectonic trends and sea-level changes, mainly in uplifting areas. If raised notches have often been used to estimate past changes in sea level and tectonic movements, submerged notches, which are more difficult to observe, have been studied mainly occasionally by a few authors. Nevertheless, Holocene tectonics may include more than a single episode and it may be useful to extend underwater observations below the first submerged notch. In this context, this work focuses in the Aegean region, an area characterized by extensional tectonics, where subsidence prevails, related to the subduction of the Mediterranean floor below the Hellenic arc, where Quaternary uplift trends tend to prevail. In some islands of Cyclades and Sporades, there is evidence of the occurrence of repeated rapid subsidences during the Late Holocene. In this paper, the shape of tidal notches that may well be preserved underwater is recalled in order to reconstruct sequences of coseismic subsidences and other relative sea-level changes that occurred during at least the last few millennia. A re-analysis of already published measurements of submerged tidal notches in several islands reveals that subsidence trends in many areas of the Aegean are not continuous and gradual, but the result of repeated coseismic vertical subsidences of some decimetres at each time. The estimated average return times are of the order of approximately some centuries to one millennium. Although the results cannot be used for short-term predictions of earthquakes, they may provide useful indications about the long-term tectonic trends that are active in the Aegean region.

Different types of sea level indicators, (e.g. geomorphological, biological and archaeological) have been used in the Eastern Mediterranean in order to assess Late Quaternary coastal evolution and relative sea level (RSL) changes. Among them, beachrocks have often been used to assess Holocene shoreline evolution and tectonically induced RSL changes in the Aegean sea. Open debate about the cementation environment and the accuracy of beachrocks as sea level indicators is still present in literature: However, in several recent studies beachrocks have been proven useful in the absence of other sea level indicators or when coupled with other available sea level indicators. In particular, the combined analysis of erosional (e.g. tidal notches) and depositional sea level indicators has great significance given the fact that erosional indicators, although more precise for RSL studies, rarely preserve dateable materials, which are more frequent in depositional landforms. In this context, we carried out a detailed mapping of beachrocks in Paros and Naxos islands (Cyclades, Central Aegean Sea). In most sites, multiple generations of beachrocks were identified, at depths varying between the present mean sea level and -6.3 m. Beachrock slabs were also sampled and thin sections were carried out for petrographic and microstratigraphic analyses, aiming to characterize the constituents, the presence of bioclasts as well as the type of the cements. In order to provide an age estimate for sea level changes in the study area during the late Holocene, beachrock samples were dated using the Optically Stimulated Luminescence (OSL) method. The study focused on both quartz and feldspar. The first OSL age estimates are presented in this study. In the last 15 years, a number of geomorphological and geoarchaeological investigations were carried out to assess the relative sea level changes in this area. Therefore, we correlated beachrocks with previously published data such as submerged tidal notches, cores on coastal lagoons and submerged archaeological remains. Here we present the results of this multiproxy study. Our results allowed both to identify the Holocene palaeoshorelines and to place a chronological framework to the sea level changes in the broad area of central Cyclades.

In the scope of the France-Greek program PLATON n° 30409XH “EMerChanCy”, this work focuses on the beachrocks of Paros and Naxos Islands, in central Cyclades, Aegean Sea, Greece, in an attempt to study their geochemistry and interpret their palaeoenvironmental significance. Beachrocks are coastal sedimentary formations, consisting of beach sediments that are relatively quickly cemented through the precipitation of CaCO3. However, debate still exists concerning their depositional environment, and therefore, their use as indicators for sea-level changes. For the aim of the present study, representative bulk samples from both islands were analyzed for their mineralogical (XRD) and chemical compositition (SEM). Chemical analyses were performed by XRF . The cement agent and the fine sand/clay fraction of the samples mainly consist of authigenic magnesian calcite, which commonly precipitates in shallow marine environments, especially in high concentration of Ca2+(>4 mol% CaCO3 or 1.2 wt.%). Furthermore, a series of clastic silicate and alumino-silicate minerals are detected. The predominant coarse fragments hosted within cement material are quartz, albite and K-feldspar. The texture of the beachrock samples varies from almost homogeneous sandstone to a mixture of lithologies, such as massive gravel, sandstone and claystone. Most of the grains are flattened and only rarely angular pieces of siliceous rocks occur, hosted in the fine-grained Mg-calcite cement. This grain size and shape is indicative of the genetic environment of beachrocks, implying the maturity level of cementation from early stage to modern situation. The beachrock samples derived from various depositional periods and depths, from the front and end slabs. The beachrocks were also correlated with stratigraphical material from boreholes and archaeological remains from the study area in an attempt to understand the coastal changes during the late Holocene in Central Cyclades.

A puzzling, slightly submerged, single tidal notch has been reported from the carbonate coasts of the northeastern Adriatic Sea. This paper attempts to explain the origin and the recent evolution of this marine erosion feature and the reasons for its uniqueness in the late Holocene. After reviewing how tidal notches are usually formed, a comparison of recent measurements of bioerosion rates carried out in the area show that when the contribution of dissolution processes can be neglected, bioerosion rates of the deepening of tidal-notch profiles appear to be very low (often <0.1 mm/y) along the coasts of Istria, in contrast to higher rates (between 0.2 and 1.0 mm/y) generally reported in other Mediterranean areas. Such a low rate of bioerosion implies a long period favourable to tidal-notch development. Several glacial isostatic adjustment computations show that relative sea level changes in the area during the last few millennia may correspond to a period of equilibrium between the regional tectonic subsidence and hydro-isostatic emergence during which relative sea level changes were limited, permitting development of the tidal notch observed. The submergence of the notch is consistent with a coseismic subsidence in late Roman time. After this, a new tidal notch could not form at the present sea level because of the limited amount of local bioerosion and the relatively large rate of sea level rise.

Important earthquakes are often accompanied by vertical-land displacements. Therefore in coastal areas they may result in rapid changes of the relative sea level. An essential tool for the study of coastal paleoseismicity is the identification of fossil paleoshorelines, paying special attention to sea-level indicators that are consistent or provide evidence of rapid relative sea-level change.Here, different types of sea-level indicators that are often used in literature in order to determine changes in fossil shorelines are summarized. Information is also provided regarding four case studies of important earthquakes that occurred in Greece (in AD 365, 1953, and 1956) and in Japan (in 1923).

Because changes in sea level may have a great impact on the distribution of mineral resources, the exploration and exploiting of these resources should not ignore the changes in sea level that may have occurred in the past in the area considered. The study of relative sea-level changes is an essential element of ocean observation and technological advances are often necessary to improve this study that includes the determination of levels (elevation or depth), chronological estimations, and the identification of appropriate sea-level indicators.Indicators of fossil or present-day sea-level positions are the most important elements for a sea-level reconstruction, because they provide information not only on the former level but also on the accuracy of the reconstruction.A classification is proposed of the main criteria that can be used to deduce appropriate sea-level indicators from geomorphological, stratigraphical, biological or archeological coastal data. Two cases studies are used as examples of sea-level reconstructions that may be useful to clarify the geology in certain areas, or to coastal engineering and coastal protection: (1) on the impact of the recent sea-level rise in the interpretation of sea-level indicators; and (2) on the foreseeable impacts of the predicted near-future sea-level rise on the coasts of NE Italy.

In this paper we attempt to map erosion and deposition zones in the island of Samos (Greece). The relief of Samos is characterized by hilly and mountainous geomorphology mantled by surface sediments and soils. The processes of erosion depends mainly on the frequency and magnitude of precipitation, surface water flow, slope characteristics, rock’s susceptibilitiy to erosion, vegetation and human impacts. The aim of this paper is to study these dynamic processes using easily updated spatial mapping processes in order to design structures to minimize erosion.

The aim of this study is to describe and assess changes in physical attributes of mesohabitat types in response to different flows in a Greek mountainous river. Hydraulic simulations were applied using two one-dimensional hydraulic models, MIKE 11 and HEC-RAS. The differences between the two models were analyzed by comparing their outputs against in situ measurements. A 200 m reach in Acheloos river was chosen as study site (Mesochora upstream) mainly because it is located in relatively undisturbed conditions (near reference conditions according to the Water Framework Directive) but also because there is intense interest for the construction of small hydroelectric plants in this area and in other mountainous rivers. For the calibration process cross-sectional transects were established perpendicular to the river flow. Transects were typically placed in areas representative of the various habitat types, proportionally determined by a habitat mapping process at a larger stream segment. Each transect was permanently marked with metal rods to allow repeated measurements in time. A 2D topographic survey was conducted and field data (water level and velocity) were collected at the transects. Also, a gauging station was installed downstream of the reach in order to provide water level data in an hourly step. Hydraulic models were applied and calibrated over a range of flows and river stages using past measurements. For selecting the control transects a thorough analysis of various parameters, such as habitat representativity, streambed slope and substrate types, was applied. In this way the habitat changes were described based on various flow scenarios over time. In a later step the results from the hydraulic models will be combined with fish habitat simulation curves (HSCs) focusing on the integration of mesohabitat and microhabitat types in the environmental flow assessment scheme.

During the implementation of fieldwork for the “Ecoflow” Cooperation project, in Acheloos River, Trikala Prefecture, Central Greece, 10 unstructured sediment samples were extracted from 3 sites along the river banks for measurements and analysis. The samples were taken from the areas of Drosochori (DR 1, DR 2 & DR 3), Aspropotamos (ASP 1 & ASP 3) and Mesochora (KOR 1, KOR 2, MES 1, MES 2, & MES 4). For granulometric analysis of the samples, the Folk &Ward method (2222) was used. As it was resulted, all samples are classified as gravelly sands to sandy gravels, poorly to very poorly sorted, very coarse to very fine skewed and platykurtic to mesokurtic. The ΧRD mineralogical analysis showed that in all the samples quartz is the major component. Calcite or dolomite [one sample] content is ranging between major through medium values. The presence of the magnesian calcite, which was found in two samples, is most likely attributed to biological sources (i.e. epiphytes, shells, etc), as commonly occur white colonies of small coral-like assemblages stack on the permanently wet pebbles observed close to the river banks. Sodium feldspars predominantly albite] are present in half of the samples as medium component and as trace component in the other half. By contrast, potassium feldspars [mainly orthoclase] are always present in minor/trace amounts. The presence of clay minerals, when considered as a group, is that of a medium or minor component. As the clay minerals content increases, the water has more suspended particles, so the river's turbidity during stormy events is strongly influenced. The higher content of clay minerals in the samples of Mesochora (downstream) indicates a different source of sediment from that of the other samples. By comparing the mineralogical analysis results with river water chemical analysis results from the same sampling sites, it becomes evident that the analyzed sediments do not provide the river waters with ions, as can be deduced from the low content of alkalies and alkaline earth metals. Sulphates and chlorides were detected in trace amounts in the water samples, whereas no sulphate minerals or halides there were detected in the sediments analysed. It is therefore concluded that there is not any buried evsaporite source in the vicinity of the sampling areas. In addition, the significantly low content of nitrates, nitrites and ammonia demonstrate the nonexistent contamination from biogenic factors. Another factor that plays a crucial role in the ecological status of the river is the availability of sediment for the development and maintenance of suitable habitats for the icthyofauna. The composition and structure of sediments affect their transportation and deposition behaviour which impacts the substrate of the river habitats. To assess this aspect in the study area, habitat suitability curves for specific fish species have been used that describe the best substrate for the necessary river habitats to support the breeding and reproduction of the particular fish species. The representation of the sample sediments in the substrate types required has been estimated by combining the results from habitat mapping, suitability curves and the sediment analyses. The results indicated that the type of material available in the particular river segments is appropriate for the maintenance and development of the habitat types that are required for a good ecological status.

An underwater geomorphological survey along the coasts of six Cycladic islands (Sifnos, Antiparos, Paros, Naxos, Iraklia and Keros) revealed widespread evidence of seven submerged tidal notches. At least seven former shorelines were identified at depths between 280 ± 20 and 30 ± 5 cm below modern sea level. The vertical succession of several submerged notches suggests the occurrence of rapid subsidence events, potentially of seismic origin. Comparison with other sea-level indicators from Naxos and Delos islands indicates that these relative sea-level changes took place after 3300 BP and provides a rough estimate of the time of development of several submerged shorelines. The submergence of the uppermost notch at −30 ± 5 cm is ascribed to effects of the recent global sea-level rise occurred during the last two centuries and, at least in part, to effects of recent earthquakes. Potential effects of the 1956 Amorgos earthquake with regard to coseismic and post-seismic vertical displacement have been recently investigated using a modellistic approach. According to the above, the lower shorelines should result from repetitive subsidence events and not from gradual subsidence.

New geomorphological investigations along the coasts of Corfu, Othonoi, Paxoi, and Antipaxoi Islands allowed the identification of recent fossil shorelines.Former sea-level positions were deduced from sea-level indicators. A ‘modern’ tidal notch, submerged c. −20 cm, was observed in all studied islands.This notch is regarded to have been submerged by the global sea-level rise that occurred during the 19th and 20th centuries at a rate exceeding thepossibilities of intertidal bioerosion. Its presence provides evidence that no vertical tectonic movements occurred since its formation. On Corfu, impactsof ancient earthquakes have left some marks of emergence at about ≥ +130 ± 11, +110 ± 11, +65 ± 11, +40 ± 11, and +25 ± 11 cm, as well as marks ofsubmergence at about −40 to −50, −85 ± 11, −120 ± 11, and −180 ± 11 cm. The emergence of +130 ± 11 cm, previously dated at about 790–400 cal. BC, was detected through erosion notches at various sites in the western part of Corfu and appears to continue even more west, at Othonoi Island. Tidalnotches submerged at depths exceeding 0.4 m were observed in the northeastern part of the island and suggest the local occurrence of a sequence offour coseismic subsidences, with average vertical displacements of 40 cm, during at least the last few millennia. At Paxoi and Antipaxoi, Holocene verticalmovements seem to have been mainly of subsidence. At Paxoi, the ‘modern’ notch was found at about −20 to −30 cm, while four more submerged tidalnotches were distinguished at about −40 ± 11, −60 ± 11, −75 ± 11, and −90 ± 11 cm, while in Antipaxoi, three submerged tidal notches were distinguishedat about −60 ± 11, −75 ± 11, and −120 ± 11 cm.

The aim of this study is to apply a state-of-the-art methodology for the estimation of environmental flows by predicting how different in-stream flows affect fish microhabitats. A habitat modelling approach was adopted to simulate and assess the ecological effects of physical aquatic habitat changes in Greek upland rivers downstream of water abstraction schemes (dams, river diversions, etc), since there is an intense debate about the construction of small hydroelectric plants in montane rivers. Two sites on the Acheloos river were chosen as study areas (Tripotamo and Mesochora upstream of the Mesochora dam), because they are located in relatively undisturbed conditions. Standard hydraulic simulation and aquatic habitat modelling was based on data surveyed along cross-sectional transects in a representative river reach. After field data collection a hydraulic model (HEC- RAS) was applied for different flows. The representative reach comprised of the habitat types and approximated proportions detected in a previous exploratory charting of hydromorphological units over a longer piece of river. Thus, a river segment for hydraulic modelling was identified in each of the study sites (segments with relatively homogeneous conditions in terms of hydrology, geomorphology, and habitats). The basic scheme of the physical habitat simulation was applied, based on a 1-dimentional hydraulic modelling, habitat evaluation with Habitat Suitability Curves (hereafter HSC) and generation of Weighted Usable Curves in function of river flow. This way, the habitat changes can be estimated for various stream flow conditions based on an indicator of habitat quantity and quality. Generic habitat suitability curves are used from Brown Trout, a relative of the native Balkan Brook Trout inhabiting local streams. In a later stage, several river flows will be integrated in the model calibration, in order to reduce the uncertainty of the model and simulate the habitat changes in terms of habitat time series within an ample range of river flows. The habitat evaluation was based on HSC; such curves are ecological models in a simple univariate format, indicating the habitat suitability of certain hydraulic conditions for a given fish species and life stage. The HSC are frequently defined by scientific studies, for the variables depth, mean velocity, substrate and cover (obtained by field observation using visual assessments by snorkelling). The habitat modelling in representative reaches enables an ecological assessment and the proposal of environmental flow regimes in the segments affected by a given water abstraction scheme. Finally, this preliminary application promotes the need for further science-based eco-hydrological approaches that are relevant to both biological quality elements and current EU policy.

Underwater geomorphological survey may reveal evidence of submerged tidal notches. In this paper, we present the methodology with the aim to reveal past temporary standstills of relative sea-level. Some examples of tidal notch development and tectonic movements are provided from fossil submerged notches mainly from Greece. A vertical movement causes a displacement of the intertidal bioerosion zone. For this reason the tidal notch profile reflects changes that occurred in the relative sea-level. If the movement is rapid a new tidal notch will be formed. On the contrary, if the movement is slower than the intertidal bioerosion rate, the height of the notch will increase. For this reason underwater marks on carbonate cliffs may provide evidence of recent vertical shoreline displacements of gradual or co-seismic origin.

The legislative framework in Greece regarding environmental flows is based mostly on hydromorphological criteria with little respect to the biotic elements of the rivers ecosystem. Nevertheless, the European Framework Directive (2000/60) outlines the importance of several groups of aquatic organisms that can be used as indices and provide valuable information about the water needs of the riverine ecosystem. Towards this direction, a habitat modelling approach was applied in this study to simulate and assess the alterations of the Weighted Usable Area (WUA) using existing habitat suitability criteria (HSC) for brown trout (adults and juvenile). Brown trout was selected because it is the most recreationally and economically important species in the study areas. Habitat models are designed for a wide variety of planning applications where habitat ecology is an important consideration in the decision process. Habitat Suitability Index curves used in this study describe the instream suitability of the habitat variables most closely related to stream hydraulics and channel structure (e.g., velocity, depth) for two life stages of the brown trout (adults and juvenile). The Brown Trout data are used provisionally to the complete absence of any local HSI development. For this preliminary application, depth and velocity values were converted into their corresponding habitat suitability index values using a GIS software. Among the HSC examined here, there were those that were cited by Boove (1978) and Raleigh et al (1986) and their development is based on literature sources or professional opinion. The demonstration applied here clearly identifies some of the utility in using HSC to potentially identify critical low-flow periods, where additional flow reductions may adversely affect water use, recreation, and aquatic species. The proposed method should be complemented with the ecological information of native fish species, and tested for transferability in other regions of Greece.

The 7 kilometers long coastline of Marathon Gulf (East Attica, Greece), has been chosen for this study, in order to classify its coastal erosion, using the Coastal Vulnerability Index (CVI) through GIS technology, since several incidents of erosion have been identified during the past decades in the area. The CVI index is used for assessing the vulnerability of a coast to an anticipated future sea-level rise. It relates geological (coastal geomorphology, historical changes of coastline’s position, coastal slopes) and oceanographic (wave height, run up and tidal range) variables in a semi-quantitative manner. We combined different kinds of datasets extracted from high resolution panchromatic aerial photographs of several time periods (1960-2010) and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematic (RTK) GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System, in order to estimate the rate of shoreline change for a period of 53 years. Retreating rates were calculated for each section reaching the value of 0.6 m/yr. According to the produced CVI values (10.61- 39.52), it is found that 46% of the coast has very high vulnerability, 20% high vulnerability, whilst 29% have low vulnerability. The area named “Plesti” at the southern part of the study area, a large segment at the coast of Nea Makri, the northern part of Agios Panteleimonas beach and the eastern estuary of the Inois river are those with the higher risk. These conclusions are in full agreement with the field observations.

part and the Karvouni mountain in the central part. The Geology of Samos consists of a metamorphic substratum, a non metamorphic unit, neogene and quaternary sediments. This island has been affected many times by natural hazards, such as forest fires, soil erosion, flash floods and gravity movements. The aim of this paper is to create an erosion risk map of Samos Island. This has been achieved by a series of separate stages, such as the creation of a database of geological, geomorphological and topographic data, extensive field observations and analyses of aerial photos and satellite images, within a GIS based platform. The final step involves the application of a functional relationship based on a probability model to input data consisting of the lithology, slope, mean altitude, and the vegetation-land use for each drainage basin to produce the final erosion risk map.

The objective of INTIMATE is to reconstruct past abrupt and extreme climate changes over the period 60.000 to 8000 years ago, by facilitating INTegration of Ice core, MArine, and TErrestrial palaeoclimate records and using the combined data in climate models to better understand the mechanisms and impact of change, thereby reducing the uncertainty of future prediction. The project is organized in four working groups: WG-1 Dating and Chronological Modelling A reliable chronological framework is the basis of all studies of the past climate. WG1 is dedicated to developing and improving dating methods over the last 60,000 years and bringing scientists together to develop a coherent dating framework in which records can be compared at unprecedented detail. WG-2 Quantification of Past Climate The aim of WG-2 is to collect and quantify information of past climate from e.g. ice cores, tree rings, corals, stalagmites, and marine and lake sediments in order to draw a detailed picture of the highly variable climate evolution in the North Atlantic region. WG-3 Modelling Mechanisms of Past Change Our ability to forecast the rates and magnitudes of future change depends on numerical models. By using combined ice core, terrestrial, and marine data sets as targets, WG-3 will optimize methodologies to evaluate model simulations and make data-model comparisons. WG-4 Climate Impacts The aim of WG-4 is to gain insights into the impacts of past climatic changes on animal and human populations and the ecosystems of which they are part. WG-4 will quantify the magnitudes and rates of population, species, and ecosystem responses to climate events of different magnitudes in space and through time.

New geomorphological investigations carried out in 2012 along the coasts of Corfu, Othonoi, Paxoi and Antipaxoi Islands have allowed the identification of recent fossil shorelines. Former sea-level positions were deduced from sea-level indicators, such as emerged and submerged notches. Notch geometries (height, inward depth and vertex depth) were measured. Due to the absence of tidal records at the closest tidegauge station during the period of fieldwork, an uncertainty of ±14 cm in depth measurements was taken into consideration. A “modern” tidal notch, submerged ca.-20 cm, was observed in all studied islands, at various sites. This notch is regarded to have been submerged by the global sealevel rise that occurred during the 19th and 20th centuries at a rate exceeding the possibilities of intertidal bioerosion. Its presence provides evidence that no vertical tectonic movements occurred since its formation. At Paxoi possible marks of erosion by waves, a few decimetres above sea level at two sites, may be interpreted as a still undetermined short-lived period of emergence. Below the “modern” notch, lower shorelines measured at –45±14 cm and-58±14 cm may correspond to the same fossil shoreline, apparently submerged by a coseismic vertical movement. At Antipaxoi, no evidence of emergence were found and Holocene vertical movements seem to have been only of subsidence; two submerged tidal notches have been distinguished at about -70 and -120 cm. On Corfu island impacts of ancient earthquakes have left some marks of emergence at about +20, +45, +110 and +140 cm, as well as marks of submergence at about -35 -50, -75, -100 and -180 cm. The emergence of +140 cm, which had been previously dated at or after 790-400 cal. B.C., was detected through erosion notches at various sites of the western part of Corfu and seems to continue even more west, at Othonoi Island.

A submarine survey along the coasts of Ithaca and Fiscardo has permitted the identification of fossil shorelines produced by recent co-seismic movements. In both areas a tidal notch slightly submerged below present MSL was observed at various sites. This “modern” notch is known to have been submerged by the global sea-level rise during the 19th and 20th centuries. The depth after tide and air-pressure correction of the vertex of the “modern” notch (= MSL before the recent sea-level rise) was measured between -19±6 and -25±6 cm at Fiscardo and between -34±6 and -43±6 cm at Ithaca. The presence of this “modern” notch at the same depth on both sides of the Ionian Thrust would give evidence that both areas were not affected by the co-seismic vertical movements that occurred in 1953 in the wider area, while a greater depth in Ithaca could be an effect of co-seismic subsidence. Both cases are discussed and analysed in this paper. Assuming that the development of the “modern” notch was produced by bioerosion, it is possible to deduce a period of relative sea-level stability before the 19th century during 2.4 to 4 centuries at Ithaca and 1.5 to 4 centuries at Fiscardo. Over the longer term, the tectonic behavior of Ithaca differs from Fiscardo. At Ithaca no evidence of emergence has been found and Holocene vertical movements have been only of subsidence: fossil submerged tidal notches can be distinguished below MSL at depths (±6 cm) of about -40 (modern), -60, -75, -90, -100, -120, -130, -140, -150 and -220 cm. A southward tilting of the island is suggested from the -110 cm notch, but this is not the case for the -70 cm shoreline. On the east coast of Fiscardo Peninsula impacts of ancient earthquakes have left some marks (±6 cm) of emergence at about +15 and +40 cm, and of submergence at about -20 (modern) -35, -50, -60, -70, -80, -90, -100 and -230 cm, with even some evidence of past uplift and subsidence at the same sites.

Tidal notches can form on carbonate coasts during periods of relative stable sea-level, or when sea-level changes occur at a rate lower than the rate of bioerosion. Tidal notches have often been used for Quaternary sea-level reconstructions and for estimating tectonic movements, especially in uplifting areas. Underwater geomorphological survey may reveal evidence of submerged tidal notches. Detailed, accurate and systematic survey along the coastal zone by boat is necessary, to access all sites and establish lateral continuity of observation. During the survey, the local lithology is taken into account. For each site, the time and the GPS coordinates are collected. Underwater, the observed features are measured in relation to sea level and photographed. Notch geometries (height, vertex and inward depth) are measured and interpreted. The accuracy can be improved by multiple measurements and by corrections based on air pressure and tidal records. Submerged tidal notches cannot be dated directly, but their age can be inferred from coastal cores or archaeological data. Information on the duration of the various sea-level positions can be deduced from assumptions on the minimum and maximum values of intertidal bioerosion in carbonate rocks. Through this methodology new evidence concerning the rates of subsidence in the investigated area may be provided. The profiles of submerged notches, resulting from different combinations of RSL in sheltered areas, allow to qualitatively distinguish the way of subsidence e.g. co-seismic event, gradual relative sea-level rise, etc. Some examples of tidal notch development and tectonic movements are provided from fossil submerged notches in Greece. Although tidal notches are not forming anymore in the present-day mid-littoral zone, underwater marks on carbonate cliffs may still provide evidence of submerged tidal notches corresponding to former sea level positions, or to recent vertical shoreline displacements of seismic origin.

The present study examines nitrate contamination and groundwater quality in the Megara basin of Attica Prefecture (Greece). Hydrochemical data were assessed using descriptive and multivariate statistical analysis to (1) classify the data into hydrochemically similar groups, and (2) to investigate geochemical and human-related factors responsible for the observed groundwater quality. Geographic Information Systems (GIS) were used to incorporate both thematic (landuse) data and groundwater chemistry to study the extent and variation of nitrate contamination and to establish spatial relationships with specific landuse types. The results indicate that more than 70% of the groundwater samples located around the national highway had nitrate concentrations that exceeded acceptable levels according to international legislation and guidelines (Directive 98/83/EC, EPA, WHO). The combined spatial analysis and statistical hydrochemical evaluation show that nitrate contamination in groundwater is closely associated with specific landuse classes and activities (e.g. agriculture, pasture, industries, urban effluents).

Through this research relative sea level changes from Late Holocene until the present day were studied, in the area of Skopelos and Alonnisos Islands. The study was accomplished through methodical underwater geomorphological research in both islands and led to the location of six and seven distinct submerged fossil shorelines, in Skopelos and Alonnisos accordingly, along the islands' coastline. Both islands have been affected during the last millennia, by repeated subsidence events, often of coseimic origin. The amount of each subsidence displacement was generally limited to one or a few decimetres, with recurrence intervals of some centuries.

Flood damages for residential and commercial/industrial areas can be direct and indirect. While direct damages are caused by physical contact of floodwater, indirect flood damages are caused through interruption of economic and social activities as a consequence of direct flood damages. Direct and indirect damages can be subdivided into primary and secondary categories as primary are the physical damages on the property and secondary damages are defined by the replacement costs. In this paper we are trying to estimate direct residential flood damages in a section of Kifissos drainage basin (Athens, Greece), taken into account the physical characteristics of the system as well as the landuse and predominant building types of the study area. Taken into account the results of this model each element of the urban environment has to be properly prepared and build capacity to cope with the current and future challenges.

In this paper, after a short summary on the processes and rates of bioerosion that contribute to the deepening of a tidal-notch profile, some Mediterranean case-studies are presented, where a tidal notch is prevented either from forming or from being preserved. Furthermore, as shown also in a complementary paper, the recent global sea-level rise is preventing the development of new tidal notches in the present mid-littoral zone. This very useful sea-level indicator, of past temporary standstills of the relative sea level in carbonate rock areas, is of great value in assisting interpretations of relative sea-level change in locations where it is preserved. The possibilities of absence of formation or of preservation, however, imply that it should be interpreted carefully before reconstructing local relative sea-level histories. In particular, the lack of fossil tidal notches cannot be relied upon to interpret the absence of past periods of relative sea-level stabilization.

Natural hazards, on a national and international scale, have increased in the last years as a consequence of climatic changes and human activity resulting in an unfavourable impact on socio-economic conditions. Catastrophic phenomena related to river floods as well as, from erosional and meteorological events, and human intervention. The Vulnerability being particularly high in the regions intensely populated, like the analyzed case study, high is the Risk. The importance of geomorphological studies in assessing natural hazards due to river floods was brought into focus with recent floods event that occurred in urban areas in NW Peloponnesus, Greece. During the autumn and winter months intense rainfalls persisted for several hours producing severe flash flood mainly in the alluvial playing of same urban streams - river. There were some loss of life and damage to buildings, transport infrastructure and agricultural crops. The damages are mainly due to absence of good alluvial playing management practices in recent decades, concretely after the year 1960 during the urban growth of towns. The most commonly visible consequences of the land-use change are flash floods observed in urban areas after high precipitation events. As important as the value of runoff formed from the watershed, is the process of reconstruction of the shape of the runoff hydrograph, especially the estimation of the time and value of the peak flow.

In a changing environment, due to the changing climate and the rapid urbanization, the cities have to develop the ability to be resilient and adapt in the present and future development. Therefore, every element of the urban environment has to be prepared and develop abilities, in order to face the future challenges, such as the floods. This paper focuses on a part of Kifissos drainage basin (Athens, Greece) in order to estimate and compare direct residential flood damages from different building types around Kifissos river. For the purposes of this study, FloReTo, a web-based tool was used. FloReTo is a web-based advisory system on mitigation measures on a micro-scale level, enabling tailored approach for the user’s own property data. As this paper deals with flood damages on a microscale-residential level, the data collected from the studied buildings include information concerning the type of property, the conditions of the buildings (old, new, renovated, etc.), type of foundation, elevations of the floors, configuration of the basement (if they exist) and first floor with a detailed description of the materials, the assets/property of the examined floors and finally information about the services of the building (electricity, heating, sewerage system). The comparison of the results of this model allows evaluating the predominant building types of the study area along with their preparedness and capacity to cope with the current and future challenges.

This study focuses on the estimation and management of flood risk in the drainage basin of Paratrechos or Peritsi stream in Naxos Island, through the study of geomorphological characteristics, geology, land use and topography. The catchment area of Paratrechos or Peritsi stream is approximately 54 km. High morphological relief characterizes the mountainous areas and lowland areas present mild relief. The average elevation reaches 245 m, while the average slope of the basin is 21%. The stream is known to have caused severe problems following intense rainfall, with landslides in the mountainous areas and subsidence in large parts of the road network, and with intense flooding events in the wider area of Chora of Naxos. Several floods have been recorded for Paratrechos or Peritsi stream, with the most recent at the end of March 1998, beginning of January 1999 and 18th February 2003. The aim of this study is the investigation of the relationship rain-runoff through Unitary Hydrographs, in order to estimate and evaluate the flood potential of the hydrologic basin. In order to obtain accurate results, the hydrologic basin was divided into sub-basins, based on the class of each stream, and the characteristics of each sub-basin were studied. For the optimum application of the Clark method, the data were enriched with field measurements, through the installation of a water level recorder and a meteorological station. The results from the field measurements were used to confirm the results of the method. Through this method, the maximum flow at the mouth of each sub-basin and the concentration time were calculated. Maps of flood risk were developed, with the use of ArcGis 9.3 software, presenting the characteristics of the flood risk locations in the study area. Furthermore, Instantaneous Unitary Hydrographs were produced for each sub-basin, in order to study and compare the relationship of rain-runoff and determine the causes of the risk. The identification of these areas and the application of the method were accomplished through the study and use of contours, elevation and trigonometric points, watersheds, land use, hydrographic network, soil characteristics, geological characteristics and flood picks.

We reassess the importance of archaeological sea level indicators along the coast of central Italy (Figure 1), recently revisited within the European COST Action ES0701. It appears that the local sea-level rise since 2000 years ago can be estimated of the order of about half a meter, that agrees with the classical literature about this topic, rather than ~1.35 m, as recently proposed. In order to analyze the contribution of glacio-isostatic adjustment (GIA) effect to sea level rise detected with observations on field, we employ different viscosity of 0.5 x 10^21 Pa.s for upper mantle and 2.7 x 10^21Pa.s for lower mantle and several late-Pleistocene ice sheets chronologies. Neglecting the tectonic contributions to sea level variations and supposing a laterally uniform rheology, in these regions, RSL curves depart from eustasy mainly because of the effects of melt water loading, responsible for a widespread subsidence reaching its largest amplitude in the bulk of the basin. The mismatch between observations from field data and model predictions can be partly attributed to the poor knowledge of the visco-elastic property of the mantle and to uncertainties of the details of the melting history. The residual between the observations and the predictions of RSL leaves some room for a contribution of recent sea level variations driven by climate change, which according to IPCC estimates amount to 30 cm globally averaged (IPCC, 2007).

A common feature of the coastal excavations in both Paros and Naxos is that of submerged antiquities and collapsed hilltops into the sea. Beach rocks along the modern coastlines bear witness to the extent and depth of ancient shores. The submerged antiquities of Paros include cemeteries of various time periods, harbor installations and certain rock-cut features whose function is not yet interpreted with certainty. The archaeologists who excavated Grotta and Aplomata on Naxos spoke of two seismic events; one at an early phase of the LH IIIA2 and another one at LH IIIC period. Indisputable evidence for those earthquakes offer two submerged tidal notches found at a depth of –3 m and –2.5 m respectively. The tsunami that covered the northern part of the Hellenistic Agora in the 2nd c. AD is additionally confirmed by a submerged tidal notch at a depth of –1.70 m and dated shells of Cerastoderma. The article proposes an entirely new perspective on the sea-level changes in Cyclades, which is strictly based on archaeological stratification and sea-level indicators.

Tidal notches are known to undercut limestone rock formations in the mid-littoral zone, especially in microtidal marine areas. Fossil tidal notches in uplifted or submerged positions have often been used to deduce former sealevel stands and tectonic movements. In particular, the good preservation of a tidal notch profile after emergence or submergence may be used as excellent evidence that the relative sea-level change was rapid, possibly coseismic. Tidal notches are believed to result mainly from marine bioerosion processes during periods of stable relative sea level. While in tropical environments their development may often include bioconstruction layers near the notch base, in temperate environment they tend to be purely erosional features, mainly caused by the boring capacity of endolithic and epilithic algae and by the grazing gastropods that rasp away the microflora together with rock particles in the intertidal range. Micro-erosion measurements have shown that the rate of deepening of a tidal-notch profile may be very variable (from less than 0.1 mm/yr to about 1 mm/yr, with averages of the order of 0.2 to 0.3.mm/yr in some sites of the Mediterranean). This high variability may depend from seasonal changes in the environment (temperature, salinity, air pressure) that have an influence not only on intertidal vegetation and grazing organism, but also on sea-level changes over seasonal or inter-annual scales. In spite of this variability, the inward depth of fossil notches may be used as an approximate method to roughly estimate the duration of a period of relative sea-level stability. All carbonate rocks are not equally sensitive to tidal-notch development: the slope of the rock layers and irregularities on the rock structure or surface may locally prevent the development of a tidal notch. This means that tidal notches may be present in some locations but not at some nearby sites. Therefore the absence of tidal notches can hardly be used as a reliable criterion to interpret the lack of a sea-level stillstand. During the last two centuries tide gauges have shown that the global sea level was rising at a rate faster than the possibilities of bioerosion. As a consequence, new tidal notches have not been forming in most places during the last couple of centuries. This is causing a general lacuna in geologic marks. In conclusion fossil tidal notches can be useful to interpret relative sea-level change in places where they are preserved. However, the lack of tidal notches does not provide evidence of the absence of a sea-level stillstand and coastal geomorphic archives are most often incomplete.

The paper Faivre et al. (2011) presents an interpretation of results deduced from two coastal cores that are trying to date the period of formation of a slightly submerged tidal notch often reported from the coasts of Istria. The development of a tidal notch in carbonate coasts is usually made possible by intertidal bioerosion processes during periods of relative sea-level stability (Pirazzoli, 1986). The inward depth of the tidal notch profile, that in Istria is often of about half a meter, may be used for a rough estimation of the duration of the period of relative sea-level stability, with assumptions on the bioerosion rates, that in the Mediterranean have been reported to vary generally between about 0.2 and 1.0 mm/y (Evelpidou et al., 2012). The profile of the Istrian tidal notch shows a well preserved roof, evidence that the notch was submerged by a rapid subsidence, probably coseismic (Evelpidou et al., 2011a, 2011b). Several publications, some of them co-signed by the same authors for the area between Porec and Zadar (Fouache et al., 2000; Faivre and Fouache, 2003), have reported, from correlation with archaeological remains, that the submerged notch corresponds, more or less, to the sea level in Roman times. Other data by Faivre et al. (2010), mention a tidal notch submerged by 0.5e0.7 m and a sea level rise from the first century AD that cannot have highly exceeded 1.0 m. Finally according to Fouache et al. (2011), the sea level rise indicated by archeological remains can be estimated at 1.0+-0.48 m since Roman times. Faivre et al. (2011) provide a new interpretation from the two cores, which is in complete contradiction with previous results, suggesting that the notch formed much later, between 1000 and 1500 AD. These two dates correspond to radiocarbon ages of two shells collected by the cores. However, apart from the depth of sampling, that nearly coincides to the base of the notch, not before but after its submergence, there is no clear evidence that the dated shells are really related to the sea level at which the notch developed before its submergence. Also, the assertion that the sample from one core would have been deposited at the beginning of the notch formation, while the sample at the same depth from the other core would just have preceded the coseismic subsidence, seems unconvincing. In fact, after the rapid subsidence of the area, the relative sea level became several decimeters higher in the areas of the Mirna River valley and of the Santa Marina Cove, permitting an acceleration in marine sediment deposition at the levels where they have been recently cored. In addition, the period between 1000 and 1500 AD seems too short for the development of the tidal notch considered, more specifically that this period seems very unfavorable to tidal notch development because the global sea-level rise that occurred until at least 1350 AD, at a rate of 0.6 mm/y (Kemp et al., 2011), has probably limited the possibilities of local bioerosion. Seismic evidence in the period around 1500 AD is also missing. If the rapid subsidence had a coseismic origin, the event is likely to have produced a tsunami in the northern Adriatic. It is hardly believable that a tsunami occurring about 1500 AD could escape notice in Venice and in the other lagoons and harbors of the western coast of the Adriatic. In short, a late Roman date, e.g. 361 AD, as suggested by Benac et al. (2004), seems more likely than a date around 1500 AD. As to the relative sea level stability necessary for the notch formation, it could have occurred in a period of balance for relative sea level changes between the eustatic, isostatic and tectonic factors (Pirazzoli, 2005), i.e. before and during Roman times, possibly in accordance with relative sea-level variations of the type of those predicted with the modelm-2byAntonioli et al. (2007, Fig. 9C or 9D).

An underwater geomorphological survey along the coasts of six Cycladic islands (Sifnos, Antiparos, Paros, Naxos, Iraklia and Keros) revealed widespread evidence of a recent 30–40 cm submergence, part of which may have seismic origin. Comparison with information reported from earthquakes having affected the area suggests that at least part of the recent submergence might be an effect of the 1956 Amorgos earthquake. Modelling of the co-seismic and short-term post-seismic effects of the earthquake revealed that part of the observed subsidence may be explained in some of the islands by a fast post-seismic relaxation of a low-viscosity layer underlying the seismogenic zone. However far-field observations are underestimated by our model, and may be affected by a wider deformation field induced by the largest aftershock of the Amorgos sequence, or by other earthquakes.

The recent rise in global sea level is causing the disappearance of an important geomorphological sea-level indicator, the tidal notch.Tidal notches have often been used in carbonate coasts for Quaternary and late Holocene sea-level reconstructions and estimation of tectonic movements, especially in uplifting areas. In this paper, we review the rates of tidal notch development, and examine the recent gradual depletion of this feature, during at least the last century, and its relation to the increasing rates of sea-level rise. Some examples of tidal notch development are provided with fossil submerged notches from Greece. Although tidal notches are no longer forming in the present-day mid-littoral zone, underwater marks on carbonate cliffs may still provide evidence of submerged tidal notches corresponding to former sea-level positions, or of recent vertical shoreline displacements of seismic origin.

Detailed mapping along the northwestern coastline of Euboea has provided new evidence of colonization by Lithophaga lithophaga (L.) reaching about 3.8 m above the present biological MSL. Such marine biological marks, together with morphological notches, correspond to the occurrence of two sequences of Holocene vertical displacements higher than those reported by previous studies, on the central part of the southern coast and along the northern coast of the island. A well developed emerged notch is found at + 1.7 ± 0.1 m above present mean sea level, whereas the uppermost part of the lithophagid holes suggest a former emerged shoreline at least at + 3.8 ± 0.1 m. Radiocarbon AMS dating of Lithophaga shells found in their burrows, showed that the lower uplifted shoreline corresponds to a tectonic event (probably coseismic) apparently dated at 2200 a BP, while the higher shoreline corresponds to an older relative sea-level transgression, possibly of tectonic origin, apparently dated about 5570 a BP. The apparent radiocarbon age of lithophagid shells can be about 350 to 400 years older than the uplift event that exposed them, due to incorporation of host-rock carbon. Nevertheless, the two new paleoshorelines provide evidence that repeated uplift movements, greater than those reported by previous authors, occurred during the late Holocene, uplifting the western part of the island.

Naxos Island is situated in the Cycladic plateau (middle Aegean Sea) and consists of concaved beach zones separated by small headlands. This study investigates the diachronic palaeo-shoreline shift due to the sea level change and its effect to the palaeo-environmental evolution of the western coastal part of Naxos Island during the Late Holocene. For this purpose, six boreholes were drilled and dated using radiocarbon techniques. The associated geomorphological, sedimentological and paleontological investigation concluded that during Late Holocene, the embayments of Naxos western coastal part were frequently exposed, and their communication with the sea was not perennial. The coastal area was wider with many active lagoons and embayment changing from shallow marine environment to coastal environment frequently alternating to brackish mesohaline one. The former sea-level position in western Naxos island should be between −1.5 m and −2 m during the last 2000 years, which may partly reflect eustatic processes and partly a gradual or coseismic land subsidence.

We present estimates for late Holocene relative sea level change along the Tyrrhenian coast of Italy based on morphological characteristics of eight submerged Roman fish tanks (piscinae) constructed between the 1st century B.C. and the 2nd century A.D. Underwater geomorphological features and archaeological remains related to past sea level have been measured and corrected using recorded tidal values. We conclude that local sea level during the Roman period did not exceed 58 ± 5 cm below the present sea level. These results broadly agree with previous observations in the region but contrast with recent analysis that suggests a significantly larger sea level rise during the last 2000 years. Using a glacial isostatic adjustment model, we explain how regional sea level change departs from the eustatic component. Our calculation of relative sea level during the Roman period provides a reference for isolating the long-wavelength contribution to sea level change from secular sea level rise. Precise determination of sea level rise in the study area improves our understanding of secular, instrumentally observed, variations across the Mediterranean.

Lechaion’s ancient harbor is now a coastal swamp filled with sediments. Two natural factors explain the harbor’s abandonment: (1) tectonic uplift during historical times and (2) the location of the harbor basin in a serpentine depression protected from the sea. Although it undoubtedly functioned as a very efficient sediment trap, only modest sedimentation rates (<1 mm/yr) have been measured in the basin. This paradox suggests that the basin was dredged and that the extracted sediments were dumped, forming a number of mounds around the harbor edges. The transition from marine organics to silt is dated to 750–400 cal. B.C. and precedes the 1.2 m uplift of the harbor at around 340 B.C., which underscores the minimal impact of tectonic forcing factors. The presence of fine-grained sediments is consistent with an increasingly protected environment. The macrofauna indicate a low-energy environment enriched with organic matter and brackish conditions. All data suggest that this environment became isolated from the sea. Although a seismic uplift around 340 B.C. played a partial role in the evolution of the harbor, it is not the sole natural forcing agent involved in the silting up of the basin.

Detailed mapping along the coasts of Skyros Island (Aegean Sea) provided new evidence concerning the rates and the modality of subsidence in the area. The results are provided through the study of the shape and the dimensions of the two submerged notches detected around the carbonate coasts of the island.It is apparent that the island has been submerged not only due to the global sea-level rise during the last two centuries (1.8 ± 0.3 mm/year between 1950 and 2000), but also because of tectonic events testified by the type of the submerged notches. Some of these tectonic events seem to be of gradual and some of co-seismic origin. The transition of MSL from the retreat point of the lower notch to the retreat point of the upper notch seems to have been produced by co-seismic subsidence of about 55 cm at slightly less than 850 years BP.

The aim of this paper is to provide further information of the tafoni development. At Theologos area, Fthiotis Prefecture, north Euboean Gulf, a carbonate formation hosts a variety of well developed tafoni. 165 tafoni were, randomly, selected by means of a detailed geomorphological investigation. The presence or absence of lichen cover, rock flaking, and cavern floor debris, amalgamation, salt flakes, different kind of structures, biological communities, were noted, while measurements regarding their dimension took place. Surface hardness values, obtained using a Schmidt hammer. Although, there is no evidence of the key factor that drives the growth of tafoni, salt weathering and low strength seems determinant of their formation. Moreover, much of the evidences suggest that joints are actively influencing the origin and the morphology of tafoni. It is possible that tafoni formation is initiated at weak zones. The studied tafoni are actively developing and are not relict features inherited from a past environment. It seems that their evolutionary stage is II towards to III. The results of chemical and mineralogical analysis indicate that during the cavernous weathering, silica, sulphates, alumina and iron oxides have replaced carbonate grains. Also, at the non-weathered part of the rock, the main mineralogical phases are calcite and dolomite.

Naxos is the largest island of the Cyclades (Aegean Sea, Greece), covering an area of ca 450 km². Its 150 km long coasts exhibits various morphological features such as cliffs, lagoons and beaches. These latter are largely preserved along the western coast, between the main city (Chora) and Pyrgaki, and are associated with well-developed dune fields. A few dunes fields are also preserved along the Eastern part (Azala Bay, Psili Ammos). Field study made it possible to propose an updated geomorphological mapping of the dune fields. Four landforms have hence been recognized, especially on the basis of their form, size, location and vegetation cover. Assuming that these various landforms relate to at least three Holocene aggradation periods, a geochronological approach was developed in order to unravel the climate influence on the Naxos dunes formation. 24 OSL dating were performed at the Leibniz Institute for Applied Geophysics (LIAG, Hannover, Germany) on samples from two main dune fields : Aliko (West coast) and Psili Ammos (East coast). We here present the first results and interpretations of these geochronological research.

Global models of glacio-isostatic adjustment (GIA) depend critically on assumptions about the rheology of the mantle and the history of ice melting since the Last Glacial Maximum. Here we employ different viscosity profiles in the range of 0.4 x 10^21 Pa.s for upper mantle and 4 x 10^21Pa.s for lower mantle and several late- Pleistocene ice sheets chronologies to interpret relative sea level (RSL) observations collected along the Tyrrhenian coasts. Neglecting the tectonic contributions to sea level variations and supposing a laterally uniform rheology, in these regions, RSL curves depart from eustasy mainly because of the effects of melt water loading, responsible for a widespread subsidence reaching its largest amplitude in the bulk of the basin. We reassess the importance of archaeological sea level indicators along the Tyrrhenian coasts of Italy (Lazio, Italy), recently revisited within the European COST Action ES0701. It appears that the local sea level rise since 2000 y ears ago can be estimated of the order of about half a meter, that agrees with the classical literature about this topic, rather than ~1.35 m, as recently proposed. The mismatch between observations from field data and model predictions can be partly attributed to the poor knowledge of the visco-elastic property of the mantle and to uncertainties of the details of the melting history. By forward modelling based on a modified ICE5G chronology, and using data from Tyrrhenian coast of Italy and SE Tunisia, we also evaluate the effects of a melt water pulse of the history of RSL, according to distinct assumptions about its origin (Antarctic or Northern Hemispheric).

This research applies the fuzzy set theory via Geographical Information Systems (GIS) - based analysis to investigate the slope erosion by water. The main steps of this procedure are the definition of the input variables (rocks’ susceptibility to erosion, slope angle, slope morphology), the development of a fuzzy inference system based on theoretical and empirical knowledge, transforming the input to output variables (erosion – deposition) and the visualization of the output variables (spatial distribution of the erosion-deposition processes). The method was applied at the Corinth drainage basin, located in the north-eastern part of Peloponnese (Greece), where a series of catastrophic erosional events have recently occurred.

Detailed mapping of coastline around Theologos area revealed the existence of well developed permanently submerged notches 75 ± 10 cm below present mean sea level. The regional occurrence of well preserved submerged tidal notches suggests their coseismic origin. The submergence of this Holocene shoreline possibly occurred at 1894 AD. Average submergence rate of 6.08 mm/yr may be estimated by a well preserved recumbent U-shaped notch. The retreating point depth suggests that the developing period of the notch might have been of the order of as much as three thousand years. Several non in situ large rock blocks, containing marine fossils (Lithophaga, Vermetids, Serpulids) in growth position, seem to have been projected on the coast by a tsunami wave, which might have been caused by the same coseismic episode.

The assessment of an aquifers’ vulnerability to pollution is of great importance, and can be used as a tool to augment planning, effective protection and management of groundwater resources’ quality, especially in the case of karstic aquifers. The present study aims to assess the intrinsic vulnerability of a karstic groundwater system, with the use of a modified version of the PI method. The assessments are functional to the effectiveness of the protective cover, as well as to the degree to which the protective cover is bypassed due to flow conditions. The used data was obtained by field work, empirical and semi-quantitative approaches regarding lithology, fissuring and karstification of bedrock, soil characteristics, hydrology, hydrogeology, topography and vegetation. The combinational effect of the above parameters, as processed with the aid of a GIS system, yielded the final calculation of the protection factor (π) and subsequently the vulnerability of the aquifer to pollution.

This paper focuses on the study of the geomorphological processes and the impact of neotectonic deformation on the geomorphological structure. A vast database was developed, containing different kinds of information, concerning geology, topography, drainage characteristics, vegetation and land use of the Ionian Islands. A geographic information system platform was developed in order to analyse the data, and to model and finally map the prevailing geomorphological processes: the erosion and deposition zones.Erosion risk factors have been processed in order to develop erosion risk maps demonstrating vulnerable to erosion areas. This study also concludes that the Ionian Islands are strongly influenced by the neotectonic processes that have defined their current morphology.

Present morphological and tectonic image of Ikaria island is the complex result of both the tem-poral evolution of the island, as part of the geodynamical evolution of the Hellenic Arc, especially that of the last stages (from the upper Miocene and after), and the exogenous factors. Also human impact functions as an additional parameter for the formation of Ikaria geoenvironment.According to field data and their analysis, computing and estimation which took part with the use of modern technologies (use of GIS, analysis of geographical and descriptive databases) the mor-photectonic units of Ikaria Island were defined. The definition of the morphotectonic units was based on their special features and more precisely on the lithological differentiation (granite, metamorphic rocks and post alpine formations) as well as the complex ductile and brittle structures (large scale ductile shear-zones and brittle detachment faults, normal faults, strike-slip transfer faults and join sets) and the morphological features (slope distribution, asymmetry of the drainage system, planation surfaces, morphological discontinuities etc).The synthesis of the special features of each morphotectonic unit in combination with the human impact (fires, overgrazing etc), defines the kind, the intensity and the geographical localization of the natural hazards which occur in various sites of the island, such as landslides, erosion, floods, seismic activity, relief changes, coastline changes etc.

Environmental history often reveals the contribution of humans in the modification of natural environment, always in relation with the climatic factors. Archaeological settlements may be preserved through desiccation, however, they are commonly found in floodplain sediments. Archaeological evidences may provide with useful information about the processes and extent of environmental changes, but they may also be used as tools for the analysis of floodplain sedimentation, relative chronology of sedimentation events and for the geomorphological evaluation of the particular archaeological site. The characteristics of archaeological indicators and the deposits in which they occur, may indicate important aspects of their source, transportation way and age. Evidence of river migration may be found in alluvial plains, through careful observations. The study area is located in Kalavrita region in northern Peloponnese. The archaeological excavations carried out revealed the fortification wall of the ancient city of "Kleitor"which is dated between the 3rd and 2nd century BC (Hellenistic Period). It may also provide clues for land surface development, reworking of sedimentary deposits, paleoenvironmental and climatic conditions. Sediments indicating considerable climatic changes are alluvial deposits of considerable thickness, covering areas with human impact. All the aforementioned become a tool for dating the course changes of the rivers and consequently a geomorphological instability. The relationship between geomorphology and history is recognizable also in the settlement distribution. This close relationship between environment and man provides a tool to understanding the landscape evolution from a geomorphological and historical point of view.

Paros Island is part of the complex of Cyclades Islands, situated in the central Aegean Sea, Greece. The climate of Paros Island is representative of the Mediterranean type, with abrupt rainfalls and lower temperatures during winters and long term sunshine accompanied by dry periods during the summer, conditions able to cause severe problems on the land. The island's low vegetation leaves the ground exposed to erosion. Also, the recent change from the local's people agricultural activities to touristic ones-especially the abandonment of the agricultural terraces during the last 50 years-has influenced the soil cover of the island in an unfavorable way, leading to total soil loss and exposure of the bedrock in many areas. Aggravating this fact, the island's steep slopes render soil regeneration almost impossible. The transferred soil is either moving towards the small alluvial plains or, in most cases, is being deposited directly to the sea. In the following paper an effort is being made to depict the currently existing situation on the island by delineating the areas still appearing to be at a high risk for erosion and to estimate the average amount of soil loss. For the later, the Universal Soil Loss Equation (USLE) was tested on the data of the island. The application of the USLE was implemented via MapInfo and ArcGIS Tools Software. The main result of the present study is that it outlines the areas where severe erosion might occur and also gives a good example for land users what is the best scenario o protect their land against erosion and which plant they should use or avoid to protect their soil from erosion.

The possibility of Holocene subsidence along the northern coast of the Corinth Gulf is often mentioned in the literature; however, systematic detailed evidence that submergence (e.g. of archaeological remains) does not simply depend from eustatic sea-level rise is most often missing. In this paper, a new detailed study of submerged tidal-notch profiles along the limestone coast has shown that periods of sea-level stability are intercalated with periods of rapid subsidence or gradual relative sea-level rise. It appears that most of the sites considered, seem to have been affected by a relatively recent co-seismic subsidence of about half a meter, whereas during the longer period, by stages of relative sea-level stability and/or gradual relative sea-level rise. This evidence of subsidence is confirmed by radiocarbon dating in doline sediments, suggesting that during certain periods, a relative sea-level rise was much faster than the raising suggested by glacio-eustatic or hydro-isostatic estimations. Juxtaposing a list of known earthquakes occurred in the area shows that several earthquakes (e.g. the 1981 one for the easternmost sites considered) are potential candidates for the recent co-seismic displacements and thus supporting the geomorphological interpretations.

The study area, Mesokambos, is located at the SE coast of Samos Island situated at the east-central part of the Aegean Sea. Mesokambos is an alluvial valley situated on the outskirts of Pythagorion, a town built on top of the ancient town of Samos which is believed to be inhabitant since at least the Late Neolithic period (4th millennium BC). Archaeological evidences indicate that the present morphology is associated with recent coastal subsidence which comes in contrast with the uplift of the North West coastal area of Samos Island. For the purposes of this study detailed geomorphological mapping, paleontological, sedimentological and radiocarbon dating analyses of the Late Holocene coastal zone were conducted. The study of sea-land interactions during Upper Holocene, in relation to the eustatic sea level rise, as well as the geomorphologic observations and analyses on deposited sediments, aims to reveal the palaeogeographical evolution of the landscape. To obtain information about the Holocene stratigraphy under the recent alluvial cover, eight boreholes followed the detailed geomorphological mapping. The paleontological analysis took place and ten samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS radiocarbon techniques providing temporal control of the sediments. In this study the tracing of the diachronic palaeo-shoreline shift due to the sea level change and its effect to the palaeo-environment in the south-eastern part of Samos Island was attempted. Sea level changes along with local conditions have been studied and the palaeogeographical evolution of the last 6.500 has been verified.

The study area of Vigla coastal zone is located at the W coast of Naxos, the largest island of Cycladic plateau. The study of sea-land interactions during Holocene in relation to the eustatic sea level oscillations as well as the geomorphologic observations and analyses on deposited sediments, aims to reveal the paleogeographic evolution of the landscape and its impact to the overall cultural development of the area. A geomorphological mapping of the coastal area along with the drilling of three boreholes has been accomplished. Moreover, a micro faunal analysis has been performed. Five samples of plant material, chart coal and shells were dated using AMS and Conventional radiocarbon techniques providing temporal control of the sediments. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 5000 BP have been verified.

The palaeo relative sea-level indicators are the most important type of data as far as the Glacial Isostatic Adjustment (GIA) related to the Last Glacial Maximum is concerned. The geomorphological and archaeological indicators have recorded the long-term sea-level variation that accompanied and followed the melting of the Late Pleistocene ice sheets. This bathymetry change stems for the combined effects of the eustatic sea-level change, the gravitational interactions between the geoid and the ice sheets and the deformation of the solid Earth. Since these three factors are fully described by the sea level equation in a self-consistent manner, the comparison of relative sea-level (rsl) data and predicted Holocene curves provides fundamental constraints on the GIA models. While the rsl data from the formerly glaciated area may provide constraints on both the extent and thickness with time of the ice sheets and the local shallow Earth structure and rheology, the palaeo sea-levels from the Mediterranean Sea may constrain the volumes of melt water that has been globally released through time and also the lower mantle rheological parameters. In this work we combine archaeological and geomorphological rsl indicators with GIA-model predictions to investigate the Holocene sea level changes in Tunisia and Cyclades islands (Central Aegean). While the former area has been proven to be vertically stable on the long timescale, the Central Aegean could be affected by local tectonics that would result in vertical deformations. We therefore compare at first the available rsl data from Tunisia with GIA predictions based on a suite of available late Pleistocene ice chronologies and Earth rheological models. We find the best combination of ice and earth models to explain the rsl data from Tunisia and finally apply those to investigate the vertical stability at the Cyclades islands and to quantify the tectonics-related rates of vertical crustal deformation.

This paper is an attempt to reconstruct the Holocene geomorphological evolution of the Kambos coastal - alluvial plain, situated in the southern part of the island of Samos between the ancient city of Samos (contemporary city of Pythagorio) and the temple of Hera (Heraion). The present morphology of the site area is shaped by the fluvial action of Mavratza Torrent forming an extensive alluvial fan in the northern part of the plain, while further southwards a drained freshwater marsh close to the sea exists. Heraion is located about 6km westwards of the ancient city. The habitation of the site area started approximately in the 11th century BC and has been constant to this day. Samos city enjoyed its greatest prosperity in the 6th century BC, under the leadership of the tyrant Polycrates. To reconstruct the geomorphological changes of the plain’s area, a detailed geomorphological survey in combination with stratigraphical and palaeontological techniques took place. In addition, a drilling project of two vibracores was carried out. The chronostratigraphy of the cores was determined by two C14-AMS radiocarbon datings undertaken on in situ bivalves. The evaluation of the data gives rise to the following time-scenario concerning the geomorphological evolution of the area. Long before 2700 BC, the area was covered by fluvial sediments originating from the nearby torrents to the north. Predominance of sandy fraction and a low percentage of silty-clayey material may indicate a process that removed the fine material. Absence also of coarse clastics (pebbles, cobbles) indicates restricted fluvial transportation and subsequently a low gradual relief. By ~2700 BC the area had already been flooded by sea-level rise and a shallow lagoon with a sandy bottom was formed. The lagoon continued to exist for a further ~2000 years, progressively becoming muddy; it was restricted and gradually transformed into a marsh. This marsh endured until the final decades of the previous century before it was drained. The aforementioned results strongly encourage the idea that the paved road connecting the ancient city to the temple in the 6th century BC must have been situated more inland, avoiding the coastal lagoon.

In this paper we examined whether the recorded precipitation changes cause erosion in Naxos Island, Greece using precipitation indices derived from daily precipitation totals, during the period 1955–2007, in order to develop an erosion risk model. Although the mean annual precipitation appear to be low (~360.0 mm), the erosion processes of the area are very intense, because of the intensive character of precipitation, the high slope relief, the differential lithology and the absence of important land cover The results of the analysis showed that the climatic changes in precipitation and the changes in land cover and land use are the main drivers for the erosion. This is why the 2nd (1971–1985) and 3rd (1986–2007) studied sub-periods may be called of high erosion risk, and especially the second one mainly because of the increased frequency of extreme precipitation events.

The Saint Georgios coastal zone, located at the W coast of Naxos, the largest island of the Central Aegean Sea, was investigated in order to determine the palaeo-geography, sea level changes and their effect to the palaeo-environment of western Naxos island and to human activity. Detailed geomorphological mapping, study of micropaleontological and sedimentological characteristics and dating analyses of the Late Holocene of St. Georgios coastal zone were conducted.To obtain information about the Holocene stratigraphy under the recent alluvial cover, three boreholes followed the detailed geomorphological mapping. Microfaunal analysis took place and five samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS and conventional radiocarbon techniques providing temporal control of the sediments. The sea-land interactions during Upper Holocene, in relation to the eustatic sea level oscillations, as well as the geomorphologic observations and analysis on deposited sediments, aims to reveal the palaeo-geographic evolution of the landscape and its impact on the archaeological sites. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 6144 BP have been verified.

The study area of St. Georgios coastal zone is located at the W coast of Naxos, the largest island of Cycladic plateau. The city of Naxos, located approximately 2.5 km from St. Georgios, is believed to be inhabitant since the early Cycladic period 5000 years ago. Archaeological evidence from Mycenaean times indicate the presence of a port whose remains along with a coastal road are found today underwater to a depth of about 2 m. In a distance of approximately 1.5 km from St. Georgios the archaeological site of the four temples of Yria, dedicated to god Dionysus, is situated. The first of the four temples is dating in the 8th century BC, while the last one in the 1st century AC. Moreover in Stelida area, adjacent to St. Georgios coastal zone, the existence of an ancient quarry is significant for the understanding of the palaeoenvironment of this area as well as the connection between these two archaeological sites. For the purposes of this study detailed geomorphological mapping, micropaleontological, sedimentological and dating analyses of the late Holocene coastal zone were conducted. The study of sea-land interactions during Upper Holocene, in relation to the eustatic sea level oscillations, as well as the geomorphologic observations and analysis on deposited sediments, aims to reveal the palaeo-geographic evolution of the landscape and its impact on the archaeological sites. To obtain information about the Holocene stratigraphy under the recent alluvial cover, four boreholes followed the detailed geomorphological mapping. The microfaunal (benthic foraminifera) analysis took place and ten samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS and conventional radiocarbon techniques providing temporal control of the sediments. In this study the tracing of the palaeo-shorelines and sea level changes and their effect to the palaeo-environment in the western Naxos are attempted. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 6144 BP have been verified.

The main objectives of this study are to identify, classify and map the badlands area, as well as to identify the underlain soil types and determine the connection between badlands and climatic changes during Quaternary. The area along the southern coast of the Central Corinth graben, near the town of Derveni (North Peloponese) was chosen as a case study, since extended erosion landforms display geomorphological characteristics, typical of badlands. The area is built up by Plio-Quaternary lacustrine clays with intercalations of distal parts of the fan deltas deposits and records an intensive structural elevation from Pliocene until today. The study focuses on the main factors that contributed in the formation and evolution of badlands in the area, with strong emphasis on geological structure, climatic and sea-level changes and human activity, as well as on the interaction of these factors. It concludes in a geomorphological map with the badlands distribution and discusses the impacts on land degradation and the possible actions against further expansion

Inland sand dune activities that set an interesting example in terms of wind erosion and accummulation in the Aegean Region under the conditions of the Mediterranean climate, and that appear on lands where the annual rainfall is about 600 mm, exist on the Akselendi Plain, Manisa. Until today, some studies have been conducted on the Akselendi Plain, which has become famous worldwide for that matter. Besides, there is an ongoing Bilateral Project with GREECE, supported by TUBITAK, some results of which will be explained in this paper. Besides the erosive winds blowing on the Akselendi Plain, the existence of mostly coarse textured alluvial deposits, the first of which is the large bed of Kum Çayı, moreover, the misuse of agricultural and non-agricultural areas have caused wind erosion, and they also caused the sediments, moving from the bed of Kum Çayı by deflation, to give great damages along with the sand dune invasion in the south of the bed. This activity has especially increased in the last fifty years. The views that we reached on the subject of wind erosion on this area and the causes, evolution and effects of sand dunes will be reported in the paper. Moreover, information will be given on the problems and on the status and efficiency of the precautions that have been taken, besides on the precautions that will need to be taken in the short term and long term. Again, the continued sand plunder because of the incorrect applications, and the effects of that on the sand dune formation will be explained. Also, some interesting formations that we determined in the last studies we conducted and that can set an example in this scientific area will be submitted to the world of science.

Karlovassi basin area has been studied for long period by the team from University of Athens. This area suffers from frequent floods which frequency even raised after large area of forests in Kerketeas Mountain area was burned down in year 2000. In recent period the area has been studied from the point of view of flood risk. High volume of data was collected and processed as an input to the flood risk model. The model was built using Arc Hydro toolset in ArcGIS environment (Maidment, 2002). Based on this model a GIS based flood risk map was created. In order to get more detail description of rainfall-runoff process a decision has been made to apply hydrologic model which works with more detail description of runoff process. For these purposes fully HEC-1 model (Hydrologic Engineering Center, 1998) was chosen. HEC-1 describes runoff process with semi-distributed approach. Results for modeling of precipitation event from November 2001 are presented here.

The upper Miocene of Karlovassi Basin, Samos Island, Greece, contain continental evaporites such as colemanite, ulexite, celestite, gypsum and thenardite. These evaporites are related with volcanic tuffs, diagenetically altered in a saline-alkaline lake environment. The aim of the present paper is to: a) define the impact of the already known and possible buried borates and other evaporites to the geochemistry of the hydrogeological system of Karlovassi Basin, and; b) to assess the correlation between surface and underground evaporite deposits considering the spatial changes in the concentrations of the examined physicochemical parameters. Fieldwork, laboratory measurements and literature data revealed elevated boron values (2136–33012 ⧎/L) in the central part of Karlovassi Basin. In the same area, high amounts of strontium, sodium, lithium and sulfates also occur. It is proposed that these ions originate from the leaching of evaporites and authigenic minerals such as the Sr-rich clinoptilolite and the boron-bearing potassium feldspar. Boron values are abnormally high for freshwater aquifers, and are indicative of the presence of buried evaporites in the basin with unknown significance.

Santorini is an island of the Aegean Sea that belongs to the Prefecture of Cyclades. It is located southern of Ios Island and, along with Anafi, these are the southernmost islands of the Cyclades. Santorini is composed of Thera, with a crescent shape, and the islands of Therassia and Aspro (Aspronisi) in a circle. In the centre of the circle lies the caldera, which was formed by a volcanic eruption (or eruptions) and the simultaneous collapse of a part of the island. Santorini caldera is one biggest of the world, covering an area of approx. 83 km2, with a length of 11 km (N–S) and a width of 7.5 km (E–W). The volcanic islands of Nea Kameni and Palaia Kameni have formed within the caldera. Nowadays Santorini is a volcanic island that belongs to the Aegean volcanic arc and, with its fumaroles, gases and a high temperature, is the only active volcano in the Eastern Mediterranean.

The Cycladic islands are located in the central Aegean Sea (Greece) forming a partly submerged plateau separated into two parts: the eastern shallower one (Andros, Tinos, Mykonos, Naxos, Paros, Syros, Ios, Sikinos, Folegandros) which formed one big island (6.978 km2) at the end of the last glacial period; the western islands (Kea, Kythnos, Serifos, Sifnos, Milos) which remained separated during the same period. The eastern islands constitute an erosional plateau which is the end product of a Neogene palaeosurface that was partially submerged due to thinning of the crust during the Quaternary. The presence of numerous Neolithic sites both on land and submerged indicates the existence of an advanced civilization in the area for thousands of years. The location of the lost Atlantis could be found in this area probably between Naxos, Paros and Antiparos.

The present contribution deals with the natural environment of Paros island coastal zone. More than 75% of the coastal zone consists of high and lower cliffs, whilst the relatively flat coastal plains are rare. The island receives a substantial amount of wave energy flux. The largest rocky and of high slopes coastal part is situated at the northeast and northwest part of the island being developed on hard (resistant to weathering processes) metamorphic rocks. Coastal plains (slopes < 2.5%) have been formed on Quaternary clastic formations. Furthermore, sandy and/or pebbly beach zones have been formed by the deposition of terrigenous (mainly) and marine sediments, along relatively sheltered from the wave activity parts of the coastline, i.e. the bays of Drios, Kephalos, Plastiras, Piso Livadi and Alikes. Palaeogeographic reconstruction with respect to sea-level rise within Holocene reveals that Paros island, at 10.000 yr BP, was much larger (some 1.025 km2) combined with the islands of Antiparos, Naxos and several islets, while at 6.000 yr BP was only connected to Antiparos island covering 264.3 km2. Finally, the predicted ca. 0.5 m of sea level rise for the year 2100, due to climatic change, will definitely threaten the socio-economy of the island as all touristic beaches will be deteriorated as well as several  onstructions along its coastline.

The coastline of Attica incorporates a great number of pocket beaches, which are characterised further by the presence of extensive beachrock formations. The present study concerns the evolution (past, present and future) of the Kalyvia beach zone, located at the western coast of Attica and at a distance of 42 km from the city of Athens. The subaerial part of the beach zone consists of mixed materials (mainly sand, granules and gravel), while extensive beachrock formations exist on its shoreface. The beach is exposed primarily to southern wind-induced waves, the largest of which (offshore wave height up to 6m and period >11sec) begin to break at about 8 m of water depth and have a run-up capability of approximately 1.5 m. Most of the subaqueous part of the Kalyvia beach zone is lithified, as the beachrocks extend from the shoreline down to >8 m of water depth. This part of the beach zone may be subdivided further into three units: the deeper one (water depths >7m), the middle (depths 5-6.5 m) and the upper unit (from 4 m depth up to the shoreline). This almost continuous presence is related to the gradual sea level rise during the upper Holocene (past 6.000 years), indicating also a relative climatic stability and/or homogeneity during this period, although some morphological and structural differences in the beachrock indicate changes either in the rate of sea level rise or in the prevailing climatic conditions. Over the last decades, human activities and constructions have deprived the beach of hinterland sediment supply, changing, therefore, its sedimentological character. During this period, beachrocks have played a ‘protective role’ stabilizing and reducing substantially the retreat of the beach zone, which on the basis of the landward boundary displacement of the beachrocks has been estimated to be in the order of 30cm per year from 1969 to 2005. This retreat is attributed to the marine erosion of the sediment that used to cover the upper beachrock formations, in combination to the sea-level rise (approx. 18 cm over the past century) and the lack of sediment supply. Moreover, this degradation of the Kalyvia beach zone is expected to be intensified by the potential future sea level rise (approximately 38 cm for the year 2100).

This chapter describes the study of the structural control of the Meganissi island coastal zone and its geomorphological evolution; based on these, it presents a coastal hazard risk map. The coastal geomorphology is affected by the lithological configuration, the tectonism, the wider seismotectonic status and the sea activity. For this study, a database has been created in GIS. using all data deriving from the above characteristics as well as from detailed fieldwork, aerial photos, satellite images and pre-existing maps. Data were analysed and processed in order to understand the geomorphological evolution of this island and its close connection with the structural evolution. Finally, we proceeded to develop a coastal hazard risk map using the slope gradient, the wave energy and the structural characteristics of this island as input variables. This has been achieved via a fuzzy inferences model using a loosen coupling between the Mat lab software package and the MapInfo GIS.

This chapter studies the counteractive dynamic marine and river environments responsible for a river mouth’s and a delta’s modulation. The Acheloos River (West Greece) was chosen as the case study due to the recent changes taken place in its Delta area; the geotechnical constructions and the agricultural planning have altered the basin’s conditions. The aim of this study is to analyze the present dominant environment and the impact of human activity on this balance with the application of modern technological tools; emphasis is placed on the geomorphological along with the land use changes taking place in the three district parts of the Acheloos’ delta within a period of four decades (1960–2000): delta plain, delta front, pro delta. Bibliographic references, geographical and geological maps, aerial and satellite imagery of different seasons and dates, were utilized in addition to extensive fieldwork measurements and mapping. A geographic database was developed and it is continuously updated.

The present contribution examines the various geomorphological, sedimentological and coastal hydrodymamic conditions that are related to the present erosive situation along the broader coastal area of the N/NW coast of Samos Island. The extended erosion, particularly evident during the past 2-3 decades, is attributed to the rise of sea level (>10 cm over the past 100 years according to IPCC report of 2007) in conjunction with the incoming relatively high wave energy, which favouring the offshore transfer of fine-grained beach material. In addition, the various man-made constructions either inhibit the terrigenous sediment fluxes to reach the coast and/or by altering coastal hydrodynamics contribute to erosion. Finally, the existed defence constructions seem to have served only to the stabilisation of the coastline and not to its natural recovery.

Weathering formations resembling small caves, known by the name of Tafoni, are a characteristic, but not exclusive, feature of the Mediterranean area. Examples of such geomorphological formations have been recorded in Sardinia and Corsica (Klaer, 1956; Frenzel, 1965), in Tuscany (Martini, 1978), in S. Spain (Mellor et al., 1997) and in the Aegean Sea area (Greece) (Riedl, 1991; Hejl, 2005).

As flash flood events are becoming more frequent, the development of flood estimation methods for areas with limited or lack of data has attracted the interest of many scientists. The aim of the present paper is to develop a GIS based methodology in order to study the flood risk in Karlovassi basin. The annual probability of a flood event is relatively high at Karlovassi area (Samos Island – Greece). Especially, after the forest fires that took place in the summer of 2000, during which 90.000 hectares were burnt in Kerketeas Mountain, the phenomenon has become more intense. Primary data were collected from maps, literature, aerial photos and field work. The collected information data were analyzed through the use of the software ArcGIS in order to generate the appropriate background for the formation of the flood risk model. All the input parameters were weighted and the model was calibrated in situ through field work. The proposed methodology and the preliminary results, as exported for the Karlovassi area, prove the suitability of GIS-based methods in the creation of flood risk maps.

The present study investigates the principal morphological and sedimentological (textural) characteristics of the beach-zones along the Tigani and Mikalis Bays, which are located at the southeastern coast of Samos Island. It is also examined their retreat due to the expected sea level rise induced by the climatic change. The beach zones under investigation has been formed in front of alluvial coastal plains, while at their western end host the mouth of small (ephemeral) rivers. Their width varies between 12 and 25 m, becoming narrower towards their eastern ends; this shows that the longshore sediment transport, which is from W to E due to their coastline orientation relatively to incoming waves, has not been strong enough to move most of the sediment eastwards. The subaerial part of both beach zones consists of gravels, while their subaqueous part is covered by sand. The presence of low dunes at the backshore odf the Thiogani Bay in association with the lack of sand between the dunes and the shoreface indicate that the beach zone is under erosion. Furthermore, with respect to the expected sea-level rise the shoreline of Tigani bay may be retreat by 15-20 m, when the nearby shoreline of Mikalis bay could retreat 12-15 m.

A geographical information system (GIS) is more than a sophisticated softwareprogram; it is a powerful tool that can be used effectively in geocultural landscape research. Geocultural landscape researchers analyze the historical content of a present landscape and its landscape evolution over time; they strive to reconstruct historical states of a landscape, using different sources, methods and techniques developed in various disciplines such as archaeology, geography, history, planning sciences as well as in related auxiliary sciences. The general interest of this study is the application of geoinformation technology in the geocultural landscape research.The introductory chapter overviews different functions of a GIS and demonstrates its role in a geocultural landscape analysis. The differences between methodology, science and GIS as a tool are presented, specifically dealing with research issues with a time and space component, as well as their representation in a computer-based system. The chapter concludes with a summary of research issues that may concern the interdisciplinary teams of both landscape researchers and geoinformation scientists.

In this paper we are examining the state of Naxos Island as far as erosion is concerned, using precipitation indexes produced from daily precipitation totals and Geographical Information System (GIS) in order to develop an erosion risk model. Naxos Island belongs to the Cycladic area and is situated at the central Aegean Sea, in Greece. The relief of the island is mountainous, with a central mountain chain crossing it from north to south. The geology of Naxos is characterised by a migmatite irruption, metamorphic rocks (schist, gneiss, marble), and sedimentary rocks (Neogenic and Quaternary deposits). Tectonism of the area is low nowadays but in the past geological time has played a major role defining the present morphology. Although the mean annual precipitation appear to be low (~360.0 mm), the erosion processes of the area are very intense, because of the intensive character of precipitation, the high slope relief, the differential lithology and the absence of important land cover. The aforementioned factors are the major contributing to the formation of the present denudated morphology mainly because of the intense run off.

This study focuses on the phenomenon of erosion regarding the coastal dune system inNaxos island (Cyclades), Greece. In the western coastal zone of Naxos, several dunefields are observed. Despite the fact that erosion on the inland has become more intenseduring the last years, providing thus sufficient material for the development of new dunefields, the current dunes are retreating.Climate variability and prolonged human activities are the major components that lead tothe dunes’ modification, which is a sign of desertification that comes in accordance withthe recent climate change. The climatic factors that are probably involved in the dunes’erosion are the aeolian blow and the precipitation, which may act in counterbalance to thedunes formation. The climatic data that were used in the analysis include daily values ofprecipitation and wind speed, acquired from the Hellenic National Meteorological Service,for the period from 1955 to 2003.This study results in the main reasons for the retreat of the dune fields, namelyanthropogenic constructions, whose intensity increases because of the touristicdevelopment on the western coastal zone, climatic conditions and wave processes.

Optically Stimulated Luminescence (OSL) dating techniques are extensivelly used in nowadays to provide chronological information of sediment material (Zacharias et al., in press) related to landscape evolution caused by natural phenomena or influenced by human activities. Within the present study, OSL was employed to provide the age profile of sand dune formations from Mainland Greece (Peloponnese) and the islands of Crete and Corfu. The application of OSL dating was practised on quartz samples extracted from the sedimentmaterial using a modified SAR protocol (Murray and Wintle 2000). The estimation of samples dosimetry was based on gamma- (Tzortzis and Tsertos, 2004) and alpha-spectrometry (Michael and Zacharias, 2000) to provide the U, Th and K concentrations. The so far dating results indicate for ages that fall within Late Holocene to modern periods (4,000 - 500 years). The study will report on the geomorphological, micromorphological and dating results in anattempt to form the environmental and chronological framework of the dune formations in Greece.

The geochemical characteristics of topsoil depend on many variables such as thelithological nature of the geological environment, climatic conditions and humaneffects. This paper focuses οn assessing the contribution of lithology to soilgeochemistry, through the process of erosion. For this purpose, extensive field workwas carried out, including lithologic recognition of formations, rock and soil samplingand finally definition of possible human impacts that affect the chemical status ofsoils. Supplementary information was adopted from the pre-existing literature for thearea, as well as from geomorphological characteristics, climatic conditions andchemical analyses of both rock and soil. Thus, a primary database has beendeveloped, in order to asses the correlation between susceptibility of outcroppinggeological formations and soil geochemical status. The area of Kopaida basin, incentral Greece, was chosen as a case study, and the final outcome was the developingof an erosion risk map for the prevailing geological formations, which may be used asuseful tool for developing appropriate strategies on environmental protection, hazardassessment and regional planning.

Erosion represents a natural process, during which particles of geologicalformations are carried away by water, wind or by their combination. It is asignificant social and economic problem, which makes research on land and watermanagement necessary. Monitoring of erosion is needed in order to predict thedevelopment of the incident and moderate it.The selected study area is the Syros Island, a small Cycladic island. In order toassess erosion risk index, a number of effective factors were used. These factorswere used as input variables of the risk model, from which derived the outputvariable that lead to the production of the erosion risk map.

The increasing worldwide apprehension of groundwater contamination problems generated the concept of groundwater vulnerability, which is based on the theory that the natural environment can offer some degree of protection to groundwater, against the natural and human impacts,especially considering, contaminants entering the subsurface environment. Although there are several methods related to the vulnerability risk assessment and mapping for porous and karstic media, there is no relative method concerning the discontinuous media. Studying groundwatervulnerability on the smaller islands of the Aegean Sea is important, because water supplies are few and avoiding contaminants entering the groundwater is vital. Tinos Island has significant water tables, as far as quantity and quality is concerned. The selected study area is theFalatados-Livada drainage system, which is developed along the lithological contact of granites and schists. In order to assess groundwater intrinsic vulnerability, a number of effective factors were used. These factors were used as input variables of the risk model, from which derived theoutput variable that lead to the production of the groundwater intrinsic vulnerability risk map.

Land use changes are sources for a series of problems but they can be solutions as well. In a nature conservation area it call reduce and increase biodiversity, however in the Tihany Peninsula nature conservationists try to protect the present natural environment. Human induced landscape changes gained the peninsula the first landscape protection district status of the Country. Geological background, microclimatic conditions, given soil heritage, plant cover and land use plays all important role in the life of the Peninsula. We wish to give an example flow human induced activities might affect the valuable natural environment ill a way that threatens the aim of the protection.

The aim of this paper is to study the historical alluviation of Thessaloniki using mainly archaeological data. Such data have been found in many places in the study-area. These findings date from the Neolithic to the Ottoman period. We have approached this problem by studying the geomorphological processes of this area and through detailed mapping of the alluviation around ancient monuments. A spatial database was created containing geological, geomorphological and archaeological data, along with all measurements collected during fieldwork. Apart from contemporary data, older topographical maps of the area were also imported and analyzed in the GIS together with the other datasets. The results indicate that deposition rates vary on temporal and spatial scales. This is due to the topography, the lithology and the climatic changes in the area. Thus, the whole landscape of Thessaloniki area has undergone continuous change; we have estimated vertical deposition rates ranging between 1,66 and 7,5 mm p.a.

The geomorphological processes, which take place on the coastal zone, are influenced by a number of environmental factors, such as lithology, climate, biota, and oceanography. The present study investigated the causes of erosion taking place on the beach zones and on the coastal cliffs along the Island of Samos (eastern Aegean Sea). On the northern part of the island the coastline is characterised mainly by rocky and craggy coasts with the beach zones to be limited and in the form of a ‘pocket’ type of beach, while on the southern part by wide and long beach zones constituted by cobbles and pebbles. Intense coastal erosion takes place mainly on the rocky coasts on the northern and especially on the northwestern part of the island. In some coastal places intense coastal erosion causes problems not only to the infrastructure (road network), but also to near-coast people’s properties. Coastal erosion is more intense on the northern coasts, than on the southern coasts, due to the differenced in the incoming wave energy, which is dominated by the more intense and frequent blowing northerly winds. Furthermore, it seems that coastline retreat is more often along parts of the coast consisting of marles, malry limestones and limestones.

In this paper the counteractive dynamic marine and river environments responsible for a river mouth’s and a delta’s modulation is studied. The Acheloos River (West Greece) was chosen as the case study due to the recent changes taken place in its basin. The aim of this study is to analyze the present dominant environment and the impact of human activity on this balance. A GIS database was developed and updated in order to provide access for future use and computer analysis (both spatial and chronological). The study, includes an estimation of the delta forming processes, the impact of the anthropogenic parameters on these processes, and, finally, their representation.

The shallow bay of St. Georgios is situated in the northwestern part of the Naxos Island and it is characterized by a 2.7 km long sandy coast consisting of fine-grained (sandy) material. Sand dunes are the landward limit of the beach zone, whilst at the southwestern part of the coast an extensive lagoon plain has been formed. A partially emerged reef and the morphologically associated Manto islet protect the middle and southwestern part of the beach zone from the most frequent (>40% annually) incoming N waves and the highest NW waves (>3 m). The coastal zone is under erosion as shown by the reduction in size (>50%) of the Manto islet and the extensive erosion of the foredunes, despite the reduction of the incoming wave energy due to the reef presence. The continuous erosion (lowering) of the reef in connection with the expected eustatic sea level rise is anticipated to cause further retreat of the shoreline, demolishing the sand dune field and inundating the nearby low-lying hinterland area.

The scope of the present research is to examine the spatial consequences of the predicted future sea-level rise upon the active area of the delta of the River Acheloos, which forms part of the NW coast of the Gulf of Patras (Ionian Sea). The growth of the Acheloos River deltaic plain, prior to the construction of dams and channelization of the lower part of the river, took place through the progradation of four main distributaries which transported 5-6 million tones of sediments annually.Following the construction of the dams, the hydraulic regime of Acheloos has changed and its propagation has ceased. The present investigation aims to quantify coastal changes on the deltaic plain of the Acheloos river due to the combined effect of (i) the process of inundation induced by a future sea level rise of 0.5 and 1 m and (ii) coastal erosion caused by the increased exposure to wave action due to sea-level rise and subsequent coastline retreat. The results of our analysis show severe shoreline recession (up to 1900m), extensive submergence of the active deltaic plain (~ 2586⋅103 m2 or 61.4 %) and elimination of most of the lagoonal areas. The substantial loss of deltaic land, accompanied by salinisation of the groundwater table, will cause severe damage to the agricultural economy of the area. Furthermore, we show that the consequences of a future sea-level rise on a low-relief fluviallydominated delta cannot be predicted accurately by simple conceptual models; instead, a holistic approach incorporating topographic, geomorphological, sedimentological, morphodynamic and hydrodynamic analyses is required.

As evidenced by the development of tools that enable proper analysis of river systems, floodplain modeling is more important than ever before. Current legislative and socioeconomic aspects of integrated water resource management often require a hydraulic analysis prior to development or construction in a floodplain. To aid in accurate floodplain modeling, scientists use computer models in planning and analyzing floodplain hydraulic situations while having difficult modeling problems depending on data needs and data availability. On the one hand, floodplain models are successful in dealing with time variation, and models with hundreds or even thousands of time steps are common. On the other hand, spatial disaggregating of the study area has been relatively simple, assuming, in many cases, uniform spatial properties or allow for small numbers of spatial subunits within which properties are uniform. Geographical Information Systems (GIS) offer the potential to increase the degree of definition of spatial subunits, in number and in descriptive detail. This paper focuses in integrating GIS and floodplain modeling in order to produce fast, accurate and easy to understand, through thematic and animated maps, results, through the development of an integrated Decision Support System (DSS). The system was applied in Prasianos watershed, Rethimnon, Crete isl., to enable prediction of spatial runoff distribution, calculate flood hydrographs and simulate the flooding following an earthen dam breach.

In the present paper we develop a software in order to describe, in quantitative terms, the time variation of the shape and dimensions of a landform. The software is based on an iterative cellular automata algorithm. In each step, the algorithm calculates the altitude and soil thickness of each cell, which represents a piece of land. The calculations are based on the continuity equation. Parameters which express the intensity of weathering of rock masses, soil transport along slopes and fluvial transport of sediments by rivers (physical processes parameters), are incorporated in the continuity equation, using empirical relations. These parameters may be time constant or time dependent. The physical meaning of a time dependent parameter is that the rate of a geomorphological process may change with time, as a result of human activities or changes in the climate. The temporal variation of the physical processes parameters are expressed by simple mathematical expressions, which may represent smooth, rapid or periodical changes.This software may be useful in geomorphological and environmental research, inorder to estimate the future development of a landform, as a result of physicalprocesses and human activities.

In this paper we investigate the relations between the landforms and thediscontinuous tectonism. A multistep methodology has been adopted. Thus, first westudy the topography of a given area and by proper procedures we classify thegeoforms. We next examine the geological formations of the area, the drainagesystem, the landuse, the vegetation and the human impact.Finally, we study the tectonic zones of this area (faults and fractures zones). Datahas also been obtained by airphotos and satellite images. All the above information is analyzed in a G.I.S platform using expert system methodology. This procedure has been applied to some selected places of the Greek territory.

Paros Island is part of the complex of Cyclades Islands, situated in the central Aegean Sea, Greece. It is characterized by the Mediterranean type of climate, with abrupt rainfalls and lower temperatures during winters and long term sunshine accompanied by dry periods during the summer, which constitutes a tough environment for the land. The low vegetation of the island leaves the ground exposed and very vulnerable to erosion. Also the recent change to the activities of the local people from agricultural to touristic ones and especially the abandonment of the agricultural terraces during the last 50 years has influenced the soil cover of the island in an unfavorable way, leading to total soil loss and exposure of the bedrock in many areas. Aggravating this fact, the slopes of the island are high in general terms thus making soil regeneration almost impossible. The soil that is transferred is either moving towards the small alluvial plains or, in most cases, is lost directly to the sea. In this paper there is an effort to depict the situation that currently exists on the island by pointing out the areas that still appear to be in a high risk for erosion and to estimate the average amount of soil loss. For the later the Universal Soil Loss Equation (USLE) was tested on the data of the island. The application of the USLE took place with the use of MapInfo and ArcGIS Tools.

Cyprus is experiencing negative impacts from flooding due to rainstorms in its urbanenvironment. There are no official figures on the extent of urban flood damage.However, the information from insurance companies is that, although Cyprus lies in a seismic region and its climate is semi-arid, the extent of the urban flood damage ismore than the extent of earthquake damage. Main causes of such damages are thelack of storm water drainage systems, the disruption of pre-existing naturalwatercourses by urbanisation, the blockage of man-made watercourses, the everchanging land use. The main effects/ impacts of these damages are the flooding of basements and low lying floors, where could me caused damages to parked cars, central heating systems, stored goods. Some consequential damage is the loss of productive time, loss of guarantees/ warranties of electrical/ mechanical equipment.This paper presents an institutional analysis, highlighting the gaps in planning,implementation, maintenance of urban flood management systems. It includes a case study of flooding caused due to institutional gaps and proposes measures to reduce the risk of urban flood damage.

The present contribution is dealing with the outcrops and the hydrogeological behaviour of the fractured rocks (mainly igneous, metamorphic and not karstified carbonate rocks, as they have been defined by the I.A.H Commission of the Hardrock Hydrogeology). The presentation starts with the description of the geotectonic regime of the Hellenic territory into the adopted different geotectoniczones. For each zone a general lithological and structural description is attempted accompanied by the description of the main aquifers and the general directions of the groundwater flow related to the formation of the rock mass fractures. Finally, an analytical description of some case studies is presented.

The Paros Island (Cyclades Islands, Aegean Sea, Greece) is characterized by a Mediterranean type of climate, while the Tihany Peninsula (Trans Danubian Middle Range Mountains, Lake Balaton, Hungary) is characterized by a Sub-Mediterranean type of climate. The Paros Island has abrupt rainfalls and lower temperatures during winters and long term sunshine accompanied by dry periods during the summer. The situation is similar in the Tihany Peninsula, except that there is snowfall in the winter and very intensive but short rainfalls in the summertime. These circumstances constitute a tough environment for the land. The low or sparse vegetation and steep slopes of the investigated areas leaves the ground exposed and very vulnerable to erosion. The recent change to the activities of the local people from agricultural to touristic ones and especially the abandonment of the agricultural terraces during the last 50 years has influenced the soil cover of the island, leading to total soil lossand exposure of the bedrock in many areas. The increase of tourist activities caused the same results however the agricultural activities have not ceased but increased a little. The slopes of the examined areas are high in general terms thus making soil regeneration almost impossible. The soil that is transferred is either moving towards the small alluvial plains of the island and inside the peninsula in Hungary. We try to compare the situation of the investigated Greek island and Hungarian peninsula bypointing out the areas that still appear to be in a high risk for erosion and to estimate the average amount of soil loss. For the later the Universal Soil Loss Equation (USLE) was tested on the data of the island. The application of the USLE took place with the use of MapInfo and ArcGIS Tools. We wish to give some details about the experiences of using the USLE model on these two territories.

The description of coastal recession is a difficult asset that is characterized by highuncertainty. This uncertainty stems from the nature of the different factors that constitute the coastal systems. Physical features such as the different geological formations, the tectonic state of the coastal area and the sea level are all factors that complicate the efforts to describe the situation. In addition, any GIS software is lacking the tools to explain or map the uncertainty factors. Therefore, it is necessary to introduce a tool that may handle the natural factors in a GIS interface. In this paper we present an algorithm that works on a GIS interface and uses grid modelingtechniques. Taking into account factors such as the geology of the areas that are examined, the drainage system, the coastal type etc., the system applies a set of user defined empirical rules, to estimate the evolution of the recession process in the affected areas. For this paper we have tested the algorithm at the island of Samos (Eastern Aegean, Greece). In the last 20 years, huge problems of coastal erosion have been observed at the northeastern part of the island near the town of Karlovassi and at the southwestern part near the Castle of Pythagorion.The algorithm may prove to be of great assistance as a decision support tool for the municipalities in these areas, since the measures that have been taken so far are temporary and do not envision the future development of the coastline.

The Karlovassi Basin is an area that has suffered many catastrophic events such as fires or floods within the last 10 years. These intense phenomena, that take place mostly at its northern part, along with the human activities, have significantly accelerated the evolution rate of the local landforms. The result is the noticeable alteration of the geomorphological landscape within these last ten years.When dealing with landscape evolution, the time is a basic factor since it determines the intensity of the morphologic development. For this paper we used an algorithm for the temporal analysis of the changes in the landscape, because of the erosional processes. The software that has been developed to apply the algorithm is GIS based and uses the concept of the cellular automata for the geospatial calculations. For each grid cell it calculates the altitude and soil thickness of the area, based on the continuity equation, which involves parameters of different natural processes such as the weathering of rocks, the river and slope sediment yield, etc. Since time is an important factor in this equation, each parameter is characterized as timeconstant or time dependent. The temporal variation of the physical process parameters is expressed by simple mathematical expressions, which may represent time constant values, as well as abrupt, smooth or periodical variations with time.This algorithm may support the local authorities in decision making issues, since it may identify the areas that require protection against the intense physical phenomena of the last years. Moreover, it may be useful in geomorphological and environmental research, concerning the way that some landforms evolve.

Sárvíz Valley is approximately 100km long, situated SW from capital of Hungary (Budapest). The total examined area of the valley is 60561.85ha. The soil cover is very mosaic, but the larger spots belong to Chernozems. We prepared the soil map of the valley, based on former soil maps, core samplings and aerial photographs. Based on the soil map we prepared the erosion map on the territory of the Sárvíz Valley Small Region Association. Erosion modeling was done by the USLE (Universal Soil Loss Equation) model. We marked areas where different amount of special attention and soil protection measures are needed. One of the basic aims of this study is the application of soil mapping and modeling for the calculation of erosion. With the help of these tools we are able to outline the areas which, as far as erosion is concerned, are in need of protection, as well as the less useful areas for agricultural production.

Kernel discriminants are greatly appreciated because 1) they permit to establish nonlinear boundaries between classes and 2) they offer the possibility of visualizing graphically the data vectors belonging to different classes. One such method, called Generalized Discriminant analysis (GDA) was proposed by Baudat and Anouar (2000). GDA operates on a kernel matrix of size N x N, (N denotes the sample size) and is for large N prohibitive. Our aim was to find out how this method works in a real situation, when dealing with relatively large data. We considered a set of predictors of erosion risk in the Kefallinia island categorized into five classes of erosion risk (together N=3422 data items). Direct evaluation of the discriminants, using entire data, was computationally demanding. Therefore, we sought for a representative sample. We found it by a kind of sieve algorithm. It appeared that using the representative sample, we could greatly speed up the evaluations and obtain discriminative functions with good generalization properties. We have workedwith Gaussian kernels which need one declared parameter SIGMA called kernelwidth. We found that for a large range of parameters the GDA algorithm gavevisualization with a good separation of the considered risk classes.

We present our experience in visualization multivariate data when the data vectors have class assignment. The goal is then to visualize the data in such a way that data vectors belonging to different classes (subgroups) appear differentiated as much as possible. We consider for this purpose the traditional CDA (Canonical Discriminant Functions), the GDA (Generalized Discriminant Analysis, Baudat and Anouar, 2000) and the Supervised SOM (Kohonen, Makivasara, Saramaki 1984). The methods are applied to a set of 3-dimensional erosion data containing N=3420 data vectors subdivided into 5 classes of erosion risk. By performing the mapping of these data to a plane, we hope to gain some experience how the mentioned methods work in practice and what kind of visualization is obtained. The final conclusion is that the traditional CDA is the best both in speed (time) of the calculations and in the ability of generalization.

This chapter concerns the application of computing technologies in Geoarchaeology. The main issue is the combination of GIS and remote sensing technologies with on-site observations of the archaeological, geomorphological and geological characteristics of the area. This combination involves gathering all the necessary information of the spatial structures: geological, topographical, geomorphological and archaeological data. The main target is the composition of the palaeolandscape in order to reveal the paleotopography of Thera and the archaeological site of Akrotiri before the Minoan eruption. GIS analytical tools may help to recreate the different phases of landform evolution of Thera before the Minoan era till nowadays. Thus, 3D models before the Minoan, during the Minoan and after the Minoan phase were produced. Furthermore, the chapter focuses on the geomorphology of Akrotiri site, the most important archaeological site on Thera. The geological formations and the dominant erosion and deposition processes were mapped in order to understand the geomorphological evolution of the area. The extensive reworking and adaptation of the geomorphology from sustained volcanic activity over a long period has resulted in huge physical changes: loss of a central area of the island, coastline modifications, soil loss, deposition and abandonment of valleys and settlement sites. This abrupt evolution have played a major role to the land use change and land cultivation, strongly affecting the local communities, perhaps emphasising and coinciding with distinctive periods of cultural expansion and contraction.

In the present paper the differential equation of the temporal development of a landform (mountain) with a time dependent diffusion coefficient is solved. It is shown that the shape and dimensions of the landform at time t are independent of the specific variation of the diffusion coefficient with time; they only depend on the mean value of the diffusion coefficient in the time interval where the erosion process takes place. Studying the behaviour of the solution of the differential equation in the wave number domain, it is concluded that Fourier analysis may help in estimating, in quantitative terms, the initial dimensions, the age or, alternatively, the value of the diffusion coefficient of the landform. The theoretical predictions are tested on a hill of the southern part of the Ural mountainous region, in order to show how the results of the mathematical analysis can be used in describing, in quantitative terms, the morphological development of landforms due to erosion processes.

The evolution of landscapes as natural phenomena is rarely seen in a generation,but in volcanic regions the landscape is transformed at a tremendously fast rate.These places are physical bounded and marked by natural phenomena as well asimbued with cultural meaning. In regions where volcanic activity is dormant, it isargued that a different cultural association is formed; in this paper thepalaeoenvironmental and volcanic evolution of the sites are analysed in thevolcanically active Mývatn region (NE Iceland) and on the island of Thera (AegeanSea, Greece).The island of Thera consists of a basement of recrystallized limestones andmetamorphosed rocks. This basement is covered by a sequence of volcanicformations. The volcanic activity, which started about 1.6 million years ago, isstill active and it is the predominant natural feature of the island’s topography.The Mývatn region is a volcanically active area, straddling the American andEuropean plates along the North Atlantic ridge. The most recent lava eruptiontook place in the 1983 and land areas are constantly changing in response to newactivities. Few of the questions that the research will approach are:

• In what way have volcanoes evolved during the last millenniums and what dramatic changes have they brought to Natural resources?
• To which extent is an active long-term natural disaster a constant threat for human presence? How is human – nature balance attained?
• Is cultural meaning projected on such a natural landmark? Which aspects of human life are directly influenced (e.g. settlement patterns, land boundaries, resources and economic activities) and which aspects are more implicitly affected (e.g. mental images, religious perspective, spiritual perceptions)?

The post-Alpine sedimentation history in Greece is mainly characterized by thedevelopment of terrestrial, marine and lacustrine successions. During the UpperMiocene salinity crisis marine evaporites, mainly gypsum, were formed in severalbasins across Greece (i.e. Ionian Islands, Crete Island). These evaporites present simple mineralogy and they are almost insoluble. As a result, they appeared to be quite resistant in weathering process and they are easily identified in the field.On the contrary, Upper Miocene evaporites of lacustrine origin have a morecomplicated mineralogy and they are rare in field outcrops in a worldwide scale, since they are commonly easily weathered. Even though, the adjacent to Aegean Sea, Western Anatolia volcanic terrain hosts a series of lacustrine evaporites, the only similar deposit in Greece is that of Karlovassi Basin, in Samos Island.The aim of the present paper is to study the erosion risk of the Upper Mioceneevaporate - bearing formations of Karlovassi basin developing a GIS model based on Boolean logic. Some of the affecting parameters that were input into the model are: the vulnerability of the lithological formations, the run off model, the morphological slopes and the aspect, the tectonic discontinuities, the land use – land cover of the wider area and the man made intervention. The geographical distribution of the aforementioned parameters, along with their modelisation, resulted to an erosion risk map of the Karlovassi basin.

During the last years the major threat for the deforested areas of the Crete island,especially the area of Moussouron municipality, is the quick wash out of soil material. The wash out of soil material, due to logging activities or fire events, obstracts efforts for reforestation and natural reconstruction of the site. For the needs of our research, the field experiments were applied at a high slope area situated at Moussouron municipality (Crete island - South Greece), where majorfire events recently took place and caused serious damages at the vegetation. Inspecific, neighboring areas of approximately 2.6km2 and 3.2km2 have been burnt in2003 and 2004, respectively. This case study area is mainly characterized by the Mediterranean climate, having extended dry periods during summer (5% of total rainfall) and periods with intensive rainfall during winter (95% of total rainfall). The area presents high relief alterations with intense slopes (~65% of the area has slopes over 20 degrees) and lithologically is mainly characterized by two basic formations; carbonate rocks at higher and schists at the lower altitudes. The aforementioned characteristics have caused the soil to intensively wash out just after the fires occurred. The main purpose of this research is to evaluate the correspondence between the amount of eroded material and the rain intensity, at conditions of recently burnt areas. In order to approach the problem, tree trunks in a parallel to the contour lines arrangement, were installed. This way the study area was split in numerous plots with predefined dimensions and precisely measured slopes. Just after each intense rainfall, thickness measurements of accumulated material were performed at each one of the tree trunks, while the runoff material was also estimated at the lowest parts of each plot. Αt the same time, using a rain gauge, rain intensity was also measured, in order to correlate this factor to the overall soilwashout. The research, performed within a period of 20 months with a total of 18 intense rain events, concludes to the rates of denudation and soil washout at non protected deforested areas and at the same time at areas were tree trunks were put as a prevention method. Particular preservation strategies and research methodologies adjusted to the needs of specific areas, may indeed act in favour of natural resources and retain ecological balance.

Development of accurate and efficient models on erosion risk mapping are difficult to be applied on different environmental parameters, mainly due to the complexity of the integrated parameters. In this study the developed GIS model is based on the theory of Boolean logic. The rules integrate the main parameters for erosion, e.g. vulnerability, slope, drainage density, although it is easy for more parameters to be added. As case study area Penteli mountain (North-East Attiki) was selected, that suffers from intense erosion, mainly due to the last severe fire events. With the aim of restraining erosional processes, combinatory strategies, such as assignment of tree trunks parallel to contours, have been applied. The results of this study include a model for erosion, deposition and material transfer. Complementary, a GIS based model was developed so as to define the movement of eroded material within the different drainage basins of the area. The model defines the erosional and depositional sites and the results are confirmed by the measurements on the tree trunks.

There is a wide range of alternative approaches to study erosion processes. In this paper the construction of a model based in the interaction of Geographical Information System (GIS) and Artificial Neural Networks (ANN) is described. The neural model uses supervised competitive learning process. The whole procedure starts with the digitization of the data and the definition of the input variables: such as slope form and gradient, lithology and vegetation - landuse. The neural modeltransforms the input variables into the erosion risk output variable. Thus, the last stage regarded the creation of an erosion risk zones map. For case study was chosen the island of Corfu (Greece). The island consists of lithologies very vulnerable to erosion and receives considerable amounts of rainfall, especially if compared to the rest of the Greek territory. Finally, the whole model was tested and the proper function of the model was confirmed by field data observations.

The aim at this paper is to study the historical allouviation of the area ofThessaloniki using mainly archeological data. Such data has been found in manyplaces in this area. These findings (buildings, castles, road traces, fortifications) dateback from Neolithic up to Ottoman period. We have approached this problem bystudying the geomorphologic processes of this area and by mapping in detail theallouviation of the ancient monuments. A spatial database has been created attributing geological, geomorphological, hydrological, other environmental and archaeological data along with all the measurements undertaken during fieldwork. Apart from contemporary data, older topographical maps of the area have also been input and analysed in the GIS together with the rest datasets. A specific methodology was applied in view of recording and studying the erosion-deposition rates. The derivative results have indicated that deposition rates vary within diverse temporal and spatial conditions. This is due to the topography, the lithology and the climate changes of this area. The study, also, reported that in some places vertical depositions rates at about 0, 5 cm/year. The applied model tracing erosional processes and deposition rates can be implemented in any other location irrespective of the environmental, spatial, or archaeological data characterizing the area.

Kernel discriminants are greatly appreciated because 1) they may express nonlinear boundaries between classes and 2) they permit to visualize graphically the data points belonging to di®erent classes. One such method is called GDA (Generalized Discriminant Analysis), however it operates on a kernel matrix of size NxN and is for large N prohibitive. We illustrate how this method works in a real situation when dealing with relatively large data. We consider a set of predictors of erosion risk in the Kefallinia island categorized into 5 classes of erosion risk (together N=3422 data items). We argue that a proper preparation of appropriate learning samples can greatly speed up the evaluations and result in good generalization properties. Our concern is to ¯nd appropriate data for learning. This is done by a kind of sieve algorithm.

Principal objective of the research was studying Roman landscapes with thecombinatory analysis of environmental, geomorphological data and with softcomputing applications such as GIS and algorithms, designed specifically forarchaeological purposes. The identification and the modeling of the possibleRoman cadastral systems via traditional methodological approaches comprised avital stimulus for the technological oriented approaches. Geomorphologicalanalysis of the landscape along with the implementation of the algorithmstrengthens the reliability of the output models and provides significantinformation for the palaeoenvironment. Modelling the spatial organisation of theRoman landscape in the area of Beziers (south France) pre-supposes acombinatory study of the physicogeographical, the geomorphological, thegeological and the archaeological characteristics of the area. Signifying the landboundaries and the road network of the area during Roman period indicates astraight forward human intervention on the landscape. Though, studying modernlandscape’s environmental settings may hinder conclusions about earlier periodsof use of the area, unless environmental data, to be added in the model, isevaluated in advance. Considering that the data collected and mapped nowadaysmay not be found in situ, emphasis is placed in the potential displacement of thearchaeological data to be input in the Roman cadastral models. In conjunctionwith the geomorphological analysis of the data, an erosion model, based onFractals philosophy, has been also developed assessing the consistency of dataused to derive possible models of Roman cadastres.

The study focuses on the application of computing elements in the field of geoarchaeology. Emphasis is placed on the meaningful combination of geomorphological and environmental data along with archaeological features within Geographic Information Systems. Principal objective was the identification and the modeling of possible Roman cadastres in the area of Béziers, in southern France. For this purpose numerous technologies have been applied; GIS, GPS, Remote Sensing techniques and Digital Image Processing methods were used for the collection, storage, digitization and analysis of geoarchaeological data. Geographical Information System (G.I.S.) was used for the processing of primary data, the production of secondary information layers, the development of the digital elevation model and its derivative files and, in essence, for the spatial and the quantitative analysis of the data. The research concluded at 3 potential Roman cadastre grids establishing orientation and distance of axes as main criteria. Further processing of the data concluded in one final Roman cadastre grid for the area of Biterrois in France.

The widespread use of the GIS tools, besides the simple mapping of areas also enabled the visualization of various spatially referenced parameters for earth sciences. Parameters such as the slope or the drainage density of an area can be calculated with the GIS tools and can be depicted in maps. In many environmental problems though, the involved variables present inexact knowledge and spatial uncertainty. This is a problem appear also when we treat erosional processes, where a number of the system input variables are of fuzzy nature, such as the erodibility, the topography’s gradient, the drainage density and the vegetation - land use. The fuzzy nature of these physical parameters, if it is to be approached by mapping tools, requires the use of special methods that will assure that the geographicaldistribution of the results will be accurate. Dealing with such uncertainties and the visualization methodologies that should follow them, is the ultimate aim of this paper. In the approach that is described here, MapInfo GIS software and Matlab are used in combination to study the erosional processes on a volcanic landscape, such us Thira Island, Greece. Mapinfo software was used for the creation of the input parameters. The management of the database was created during the digitization and the creation of the input parameters and finally for the rendering of the geographical output of the study in the form of thematic maps. Matlab software wasused for the calculations within the different parameters and the gradient leveling that were applied to the logical results. The transformation of the input variables to the output ones (erosion risk) was achieved by formulating a number of fuzzy logical rules. The final step of these processes is the development of the thematic maps.Thira Island has been chosen for this case study, because its volcanic landscape and its susceptibility to erosional phenomena appeals great scientific interest and requires the introduction of different approaches for the solution of the natural problems. Besides, the output of this study can constitute an important tool for the local authorities of the island.

Using a given data set (the Kefallinia erosion data) with only 3 dimensions and with fractal correlation dimension rGP ¼ 1:60, we wanted to see, what really by the kernel methods is provided.We have used Gaussian kernels with various kernel width ¾. In particular we wanted to ¯nd out, whether the GDA (Generalized Discrimination Analysis) as proposed by Baudat and Anouar (2000), permits to distinguish better the high, medium and low erosion classes as compared to theclassical Fisherian discriminant analysis. The general result is that the GDA yields discriminant variates permitting for better differentiation among groups, however the calculations are more lengthy.

In this paper we attempt to classify drainage sub-basins according to their erosion risk. We have adopted a multi-step procedure to face this problem. The input variables were introduced into a GIS – platform. These variables are the vulnerability of the surface rocks to erosion, topographic variations, vegetation cover and land use and drainage basin characteristics. We then constructed a fuzzy inferencemechanism to pre-process the input variables. Next we used neural-network technology to process the input variables. The above system was trained to ‘learn’ and classify the input data. The output of this procedure was a classification of the sub-drainage basins related to their risk of erosion. This neuro-fuzzy system was applied to the island of Lefkas (Greece).

Naxos is the biggest island of the Cyclades. It is composed primarily of mica-shists, gneiss and marbles and granodiorites in the western part. The latter extend along parts of the studied area. Detailed coastal geomorphological study and GIS analysis made possible the determination of coastal evolution of this area during Late Quaternary. A number of shallow drillings and archaeological evidence helped in the determination of the sequence of the coastal evolution of the study area. Two sets of coastal dunes were mapped reaching elevation of 4 and 8 m respectively, plus older well preserved dune fields reaching elevations up to 18m located in the south. It was found that three granodiorite capes were small islands at the end of the last transgression in Mid Holocene. Since then, parts of the coastline, prograded joining them and forming coastal dunes, beachrocks and wetlands in several locations.

The main research aim of this paper is to examine the slope-stream erosionalprocess in the Korinthos drainage basin located in the north – eastern part ofPeloponnese, Greece, by means of applying the fuzzy set theory on a GIS platform.The main steps of this procedure are: the definition of the input variables (erodibilityof rocks, slope angle, slope morphology), the construction of a fuzzy inference system based on theoretical and empirical knowledge for transforming the input to output variables (erosion – deposition) and the visualization of the output variables (Spatial distribution of the erosion-deposition processes). The earth’s surface is the result of endogenous (weathering) and exogenous (erosion) processes. Weathering destroys chemically, biologically and mechanically the structure and the cohesion of the rock. The erosional mechanism transports the sediment and depends on many factors such as: frequency and magnitude of precipitation, surface and subsurface waters, slope elements (geometry, length and angle), rocks’ susceptibility to erosion, vegetation cover, human actions and land use. The study of the erosional process demands a series of steps in order to obtain the final output maps. These steps include: 1) field-work, air-photos and satellite images interpretation, map digitization (geological, topographical, drainage), 2) definition of input and output variables, 3) formulation of the proper logical rules (Boolean or fuzzy) for the transformation of input variables to output variables, 4) analysis and visualization of the output results.The input variables used in this research are: erodibility of rocks, slope angle andslope morphology. The erodibility of rocks depends on many variables which showspatial and time variation. Firstly, it depends on physical and chemical characteristics of the rocks and the rocks’ structure and discontinuities. Secondly, it depends on the existence of a protective vegetative cover which contributes in the increase of the infiltration capacity and limits the runoff flow. Thirdly, it depends on the characteristics of the involved processes: the intensity and duration of precipitation and also its spatial and time distribution and its raindrop size.The input variables are inserted into a fuzzy inference system, constructed in orderto transform them to output variables (erosion-deposition variable). This is achievedby the formulation of the proper ‘if…then’ rules based on theoretical as well asempirical knowledge of the erosional processes.The output variable (erosion) expresses the degree of erosion and deposition ofthe various parts of the drainage basin and is presented through erosion risk maps of the area that is studied.

In this paper the study of geomorphological characteristics, developed because of the run off, in the Cyclades area and especially in Tinos, Mykonos and Naxos islands, has taken place. In order to explain their development, the geomorphological characteristics were correlated with the lithological, tectonical and hydrological characteristics of the study area. The study area is characterized by a wide variety of different lithological and hydrogeological factors. To achieve this study’s targets, GIS and GPS technology was used in order to geographicallyand statistically analyse the morphological, hydrological, lithological and tectonic factors of this area. The main sources were the pre-existent maps and the literature, aerial photos and satellite images, while the extensive field work resulted to the geomorphological mapping of the area. The results of this study are related to the analysis of the current morphology and are presented on maps and rodograms.

The Cycladic islands are located in the central Aegean Sea (Greece) in a relatively low seismicity area and are composed mainly of metamorphic and plutonic rocks. Although the Cycladic plateau is believed to be an entity, a closer morphologic study of the islands through GIS, separates them into two parts: the eastern shallower one (Andros, Tinos, Mykonos, Naxos, Paros, Syros, Ios, Sikinos, Folegandros) which formed one big island (6.978Km2) at the end of the last glacial period; the western islands (Kea, Kythnos, Serifos, Sifnos, Milos) remained separated during the same period. It is concluded that the eastern islands constitute an erosional plateau which is a product of a Neogene palaeosurface that is partially submerged due to thinning of the crust during the Quaternary.

This paper describes the study of the structural control of the Meganissi island coastal zone and its geomorphological evolution; based on that it detects and presents coastal hazard. The coastal geomorphology is affected by the lithological configuration, the tectonism, the wider seismotectonic status and the sea activity. For this study, a database has been structured in G.I.S. was using all data deriving from the above characteristics as well as detailed fieldwork, aerial photos, satellite images and pre-existing maps. Data were analysed and processed in order to locate zones of high hazard risk. Finally, a hazard risk map was developed for Meganissi island.

In this paper the counteractive dynamic marine and river environments responsible for a river mouth’s and a delta’s modulation is studied. The Acheloos River (West Greece) was chosen as the case study due to the recent changes taken place in its basin. The aim of this study is to analyze the present dominant environment and the impact of human activity on this balance. A GIS database was developed and updated in order to provide access for future use and computer analysis (both spatial and chronological). The study, includes an estimation of the delta forming processes, the impact of the anthropogenic parameters on these processes, and, finally, their representation.

The goal is to visualize a set of multivariate data in such a way that datavectors belonging to different classes (subgroups) appear differentiated as muchas possible. When intending such visualization, the first question should be aboutthe intrinsic dimensionality of the data. The answer may be obtained byevaluating, e.g., the fractal correlation dimension. The projection to a plane isjustified when the correlation dimension of the data is about 2. Only in such casethe performed visualization is plausible to reflect all the between group and thewithin group relationships among the data vectors. There are several recognizedmethods for mapping data to a plane. Our interest lies especially in nonlinearmethods. We consider in detail three methods: The canonical discriminantfunctions, the kernel discriminant functions and the neuroscale mapping. Weillustrate our considerations using the Kefallinia erosion data, where each datavector belongs - in a crisp way – to one of five predefined subgroups indicatingthe severity of the erosion risk. The assignments to the subgroups were performedby an expert GIS system based on logical rules established by experts.

The main purpose of this paper, is to study the coastal morphology of the five largest islands in the Ionian Sea (Zante, Kefallinia, Ithaki, Leukas, Corfu) located in Western Greece, in relation to lithology, tectonic characteristics, general seismotectonic regime and marine processes of the area, and finally to locate sites of possible future coastal retreat. The predominant lithological formation of the coasts of Zante, Kefallinia, Ithaki and Leukas, is the carbonate rocks. The shores of Corfu island are composed mainly of Neogene and Quaternary formations. The morphology of the steep coastline is determined in general by offshore normal faults having NW-SE and N-S directions and the relief steepness is intensified by the high resistivity of the calcareous formations. The low relief coasts are common in areas where Quaternary deposits are dominant. Data derived from aerial and satellite images, large scale maps and detailed fieldwork mapping were treated by GIS. The upper coastal zone limit was extended up to the 20m contour line. A coastal hazard map was developed focusing on erosion prone areas. The most vulnerable were found to be the western coasts of Leukas, south Kefallinia, north Ithaki and north Corfu. Landslides and rockfalls are especially risky in western Leukas, northern Corfu and southernKefallinia.

In this paper the area of the lakes Iliki and Paralimni are examined (Viotia). The research focuses on the influence of the tectonic on the morphological structure of the area and on the formation of the lakes, with fieldwork and the use of GIS (Geographic Information Systems). For this purpose the azimuth directions ofthe rupture zones were calculated with the use of ‘geoline orientation’ algorithm. The analysis of the morphological slopes and of the aspect was performed with the use of the algorithm ‘Triangulation with smoothing’. The outcome of the fault direction concurs with the Pliocene faults direction, as well as the tectonic Fokiko - Viotiko trough direction. The Quaternary faults direction concurs with the recent rupturezone. In general, the dominating morphological slopes are of 0-10%, while the higher slopes are found at the north and east. The aspect that concerns the direction of the morphological slope concurs with the main rupture zone of the tectonic Fokiko - Viotiko trough direction, and the recent rupture zone. The orientation of Iliki lake corresponds to the former rupture zone; the orientation of Paralimni lake corresponds to the later one.

The erosional processes depend on various variables such as lithology, topography,drainage system, rock structure and climatic conditions. The quantitative evaluation on some of the above geological and geomorphological parameters is of primaryimportance for the purpose of developing erosion risk maps. These maps can become useful tools for developing appropriate strategies on environmental protection, hazard assessment and regional planning. The island of Sifnos, in Cyclades, was chosen as a case study, where in the final map of the sub-basins of this island, erosion risk distribution is presented.

In this paper we are studying the erosional procedures on the basis of Geographical InformationSystems (GIS) and Artificial Intelligence (AI) methods. More precisely we use fuzzy logic rules toestimate the erosion risk index for the surface rocks and a model of neural networks to spatially categorisethe erosion risk index. The described procedure is applied at Zakynthos island, where acomplete spatial database already exists.

The geomorphology of Greece is the result of multiphase tectonic movements of compressional and extensional nature plus exogenous processes. In this complex relief a Mediterranean-type ecosystem has been developed reflecting the prevailing climatic conditions. The frequent occurrence, especially during summer, of strong winds and high temperatures are the main reasons for extensive fires. The aim of this paper is to develop a methodology to face with this increasing danger using fuzzy set theory in a Web-GIS platform. As a case study of this work the two of the Ionian islands, Zakynthos and Kefallinia have been chosen, which are characterized by a relatively well developed vegetative cover and frequently recurring fires. It is widely accepted that the fire management is of primary importance for the environmental protection and planning.

We compare space quantization obtained by codebook vectors yielded by Kohonen’s self-organizing maps and the neural gas methods. The average approximation error (called also the quantization error) is smaller when applying the neural gas method. The results are visualized graphically by scatterplot matrices. For the special case of 3-dimensional data the results, i.e. location of the representative codebook vectors among the original data points – are also visualized by a rotatable 3-D plot. The analysis was carried out for the Kefallinia data counting n D 3420 data vectors, each with p D 3 components. We stated that the results depend on the way of standardization of the data.

We consider a large set of data comprising N=3422 data vectors, each containing observations on p=3 variables. We find for these data representative data vectors. We do it by employing the methodology of Kohonen's self-organizing maps. The found representative data vectors are called codebook vectors. In particular we analyze two collections (assemblages) of codebook vectors counting m=275 and m=120 elements. The quantity of the representation is measured by evaluating two errors: the quantization error q1 and the topological error q2. We show for our data that the magnitude of these errors depends on the way the original data werestandardized. After a thorough graphical analysis of the results we came to the conclusion that codebook vectors obtained from data standardized by range yield a little better representation as those do which were obtained from data standardized by variance. None of the representations is satisfactory from our point of view.

In this paper the area of Iliki and Paralimni karstic lakes is studied throughfieldwork and GIS. The study area is situated east of the Fokida – Beotia tectonicdepression focusing on the relation of the tectonic activity to the formation of thesurrounding slopes. As a result of this study, slope formation is related to the two main tectonic phases of the wider area.

In this paper we examine methods of digital image processing, in order to extract drainage system branches and import them into a GIS layer. Moreover, we have developed special algorithms on GIS environment in order to analyse drainage system parameters. In order to get the optimum detection of the drainage system characteristics, we applied on the Landsat image and on aerial photos several filters. Using the aerial photos of the area, we created the orthophotomosaic, which came out of the ortho-rectified aerial photos. Via stereoscopic observation on the computer screen, we detected and digitized the drainage system branches. Using special algorithms, developed under the MapBasic programming language, we evaluated the drainage system and the faults directions, in order to analyse them quantitatively and geographically.

In this paper we are examining Salamina island from a physical-geographical anda geomorphological aspect. For the purposes of this study, we used all existed official maps, recent aerial photographs and satellite image as well as data deriving from extensive fieldwork at the study area. The results of the photo-interpretence are combined and correlated with the outcome of the primary data (physical, geological, geomorphological) that were collected through fieldwork, which took place with the use of GPS, to ensure the accuracy of the measurements. This study resulted to the creation of a geomorphological map of the study area in a GIS environment, along with several thematic maps presenting all collected data (primary and secondary). Finally, a geomorphological and environmental evolution of the study area has taken place, in order to map the genesis of the nowadays morphology.

The main purpose of this paper, is to study the geomorphological evolution of Meganisi island’s coastal zone and to detect areas vulnerable to coastal erosion.The geomorphology of the island is effected by the lithological configuration, the tectonic characteristics, the wider seismotectonic status and the sea activity of the area. The wider area is characterized by intense seismicity: strong earthquakes are very frequent (M>6) and from the seismotectonic point of view is very complex. Limestone is the main lithological formation of Meganisi coastal zone. Coastline is steep and straight with morphological slopes ranging from 0%-66%. A big part of the area (40,87%) is of high slope (>20%). A GIS was developed using data deriving from detailed inland and sea fieldwork, aerial photos, satellite images and pre existing maps. Data were analysed statistically and geographically and variousthematic maps were created such as the morphological map, map of vulnerability, etc. Data deriving from this analysis as well as from fieldwork were processed through logical rules in order to locate zones of high erosion risk. Finally, an erosion risk map was developed in order to locate those areas that are vulnerable to futureerosion and to keep attention to them.

Coastal areas are the result of a complex interaction of many factors such as rock properties, geomorphological processes and wave action. We approach these dynamic landscapes using fuzzy set theory. As input variables we use rock’s erodibility, slope gradient, (drainage density,) vegetation and land use and wave characteristics. Next we formulate fuzzy logical rules to transform input variables to output ones. The output of the system represents the coastal depositional and erosional processes. As a case study we choose the island of Corfu (Greece) which presents lithologies very vulnerable to erosion and receives very high amount of rainfalls, in relation to the rest of the Greek territory. All this procedure has been developed using a loose coupling system of a flexible GIS platform and the proper environment to process fuzzy variables.

This study is dealing with the natural environment of the coastal zone of Paros island chosen as a representative ‘sample’ of the Cyclades complex of islands and amongst the most touristic ones. More than 75% of the coastal zone consists of high and lower cliffs, whilst relatively flat (slopes <2,5%) coastal plains do not exceed the 17% of the coastline. The island receives a considerable amount of wave energy; this has its highest values (>1500 W/m) at the NE part of the island and its lowest at the SE “protected” and shallower shelf area. Touristic (sandy/pebble) beaches have been developed along those parts of the coastline characterized by Quaternary (erodible) lithology associated with moderate wave activity. Sea level rise during the Holocene has played also an important role in coastal geomorphology; for example, Paros was connected to Naxos and Antiparos islands 10.000 yr BP and to Antiparos 6000 yr BP. A further rise of sea level (some 0,5 m at the year 2100) due to climatic changes will obviously deteriorate the terrestrial part of the coastal environment and especially all the touristic beaches and related establishments along its coastline.

Geographical Information Systems are important tools for various scientificaspects. Especially sciences related to cartography and geographical analysis should definitely employ GIS technology. In this study we present an Internet – based GIS that our team developed under MapXtreme platform. This application gives access to numerous web-users through a server that controls both analysis and data retrieval requests. It is a practical and economical method in order to introduce GIS to educational institutions. This Web GIS may operate through a local or wide area network and, apart from educational purposes, offers a low cost information exchange solution between vast numbers of users.

This paper is a preliminary study of an extensive project that will take place at Corfu island (Northern island of Ionian Sea), involving the municipality of Esperion and the Remote Sensing Laboratory (University of Athens). The project’s purpose is to estimate the erosion progress at Sidari bay’s (North part of Corfu island) coastal zone, due to wave activity. Sidari area consists of Neogene formations, which are extremely vulnerable. Moreover, wave impact is also of high energy, causing subsidence of the coastal line. Through this project, our team is developing a GIS database that holds information, deriving from existing maps, bibliographical references, and climatological logs, related to geology, geomorphology and environmental parameters. Apart from those data, aerial photography stereo observation and extensive D-GPS fieldwork resulted to continual coastline monitoring and GIS database updating, for a period of 26 and 5 years, respectively.Project’s conclusions are based on quantitative and spatial analysis through GIS, giving answers on the erosion’s rate, the erosion’s impact on human activities and structures, and finally an estimation on Sidari’s coastal zone future morphology.

Naxos is the largest island (430km2) οf Cyclades complex. The relief of the island is mountainous, with a central mountain chain crossing it from the north to the south.The geology of Naxos is characterized by a migmatite irruption, metamorphic rocks (schist, gneiss, marble), and sedimentary rocks (Neogenic and Quaternary deposits). Erosion is a complex procedure, which takes place after the forming ofweathered surface material. In this study, an erosion risk map was created, with the use of GIS technology. For this purpose, the maps and fieldwork data concerning the geology of the island, as well as the topography and the geomorphology (of the area) were imported into the GIS. Subsequently, the input data of the final thematicmap were modified with the use of fuzzy logic rules, which was considered to benecessary because of the nature of the studied variables.

In this study we examined the geomorphological and environmental characteristics of south Attika coastal zone (from Voula area to Lagonisi), a region in which man-made influence is very intense. This paper includes the detection of features of the coastal zone, that are in danger of alteration, because of their exposure to human intervention; it results to the study of the above characteristics and their mapping, with a purpose of using the final thematic maps in future study of the area, after the oncoming changes, because of the Olympic games of 2004. For this purpose we developed a database with geographical, geological, geomorphological and environmental characteristics in GIS and we created the corresponding thematic maps. Data collection took place through photointerpretation of corresponding aerial photos and fieldwork of the coastal zone (from inland and offshore) with the use of GPS.

The flat terrestrial part of the coastal zone of the Paros Island (slope <2,5% forelevations 0-50 m), represents only the 19% of the total area of the island (193 km2). More than 75% of the coastal zone consists of high and lower cliffs, whilst relatively flat and sandy (and/or pebble) beaches do not exceed the 17% of the coastline. The island receives a considerable amount of wave energy; this has its highest values (>1500 W/m) at the NE part of the island and its lowest at the SE “protected” and shallower area. Touristic (sandy/pebble) beaches have been developed along those parts of the coastline that characterized by vulnerable lithology associated with moderate wave activity.

In this paper we study Samaria gorge through recognition, recording and visualization of geomorphological characteristics. Geomorphological characteristics collected through Remote Sensing techniques, are compared with those collected through stereoscopic observation of aerial photos and fieldwork. At the first phase, the aerial photos of the studied area were scanned and through selected digital image processing algorithms, the geomorphological characteristics were stressed and recorded. At the second phase a geomorphological map was created based on data derived from stereoscopic observation of the area aerial photos and fieldwork. During fieldwork a GPS was used, which was connected with the GIS in order toimmediately record and test the measured characteristic position. Finally the combination of two methods took place in order to develop a geomorphological map.

Thera, along with the islands of Therasia, Aspronisi, Palaea and Nea Kameni, form avast roundly shaped caldera, of 8x10 km. Because of the intense volcanic activity, The shape and morphology of Thera has repeatedly changed through the years. This characteristic makes Thera, from a geological point of view, a very interesting island. Paleo-environmental and volcanic evolution is quite impressive, moreover if it is expressed through modern technology, such as GIS and modern visualization tools. As far as archaeological findings are concerned, Thera is already famous for the existence of the Minoan civilization. Volcanic activity is highly linked to both thepreservation of the archaeological findings and the destruction of the Minoan civilization over Thera Island. In this study with the use of Geographical Information Systems we propose a wide cultural park, combining all physical, geological, geomorphological and cultural characteristics, and through that the connection between volcanic activity and Minoan civilization evolution.

Cephalonia belongs to Ionian islands and consists of two alpine zones, the pro-apoulia and the Ionian one, and pleiocene and quaternary deposits. In this paper we are developing a land use / land cover map of Cephalonia island and an urban map of Argostoli town, the capital of Cephalonia, using GIS techniques and photointerpretation.

We consider the problem of predicting a risk index of an event on the base of several predictors. The specificity of the problem lies in the fact, that there are no training data; instead we have a set of logical rules describing in a fuzzy way several classes of the risk (’very low’, ’low’, ’medium’, ’high’ and ’very high’ risk). We present several problems and doubts we had met when trying to construct a predictor. After considering several alternatives we stated that a simple neural network architecture (with one perceptron) calculating logistic regression has given the best agreement with expert opinion. Thus,based on the rules, we are able to mimic the expert opinion by a neural network model.

Andros is the 2nd biggest island in Cyclades. Its morphology is intense and derives from the lithological and tectonical characteristics of the island. In this paper we studied Andro’s island environmental characteristics using Remote Sensing and GIS techniques. A GIS database was developed including all the corresponding geographical, geological, geomorphological and environmental characteristics. Moreover, an environmental map was developed at a 1:50.000 scale that elaborates all the above data. Remote Sensing techniques were also used in combination to the traditional cartographical methods, in order to locate with maximum accuracy all these data and input them in the GIS.

In this paper we study the coastal zone in the region of Acheloos’ river mouth and delta. In recent years, this region has been subjected to a series of environmental changes, primarily due to intense human activity concerning large hydroelectricdams. These dams created between 1960 and 1986 are responsible for important changes of the river’s flow. The purpose of this study is to record the changes that have occurred between those years and present time; to define and analyze their possible consequences on the coastal geomorphology of the region. For this reason we used topographical and geological maps (scale 1:50.000), aerial photos (scale 1:33.000) and finally satellite photos. A geographical database has been created in a GIS with environmental, geological, geomorphological and anthropogenic features of the studied area. All digital data were analyzed spatially and quantitative in order to describe the change of delta shape, size and finally the occupied land use. Finally different thematic maps were created showing the geomorphological and environmental changes during those years.

In this paper the erosional process of northeastern coastal Attica is studied. The alpine formation, usually Mesozoic limestones and the post-alpine deposits such as conglomerates, sandstones and marl-limestones characterize the geology of this area. This area has dramatically changed in the last decade as a result of a rapid urbanization. In June 2001 this coastal area experienced a severe fire event with enormous effect of the vegetation cover. Apart from this damage the outcropping of post -alpine vulnerable formations might accelerate erosion during possible intense rainfall. All these taken under consideration turned us to the construction of an erosion risk map based on web-GIS and soft computing technology. Such approach can be very useful for regional planning and environmental management. Indeed since our first abstract (September, 2001) heavy precipitation has been occurred (November, 2001) and a vast quantity of the weathering material has been mobilized. This fact and the new data sets have strongly proved the usefulness of this study.

This study is dealing with two different transformation rules for creating erosionrisk thematic maps. The first rule, based on Boolean logic, is a well known theoryused for composing maps and demanding crisp sets as input data. The second one is the fuzzy logic theory, appropriate for handling fuzzy sets. In this context we present a case study from the Greek territory of Korinth. It concerns the hydrological basin where recently a catastrophic flood event has occurred. As input data we have used field measurements, aerial photos, satellite images, topographic and geological maps. These data sets were georeferrenced, digitised and introduced to a G.I.S. – web platform. The G.I.S. – web technology permits easy data and map updates. Oursoftware tools were the MapInfo G.I.S., the MapXtreme web interface and theMatLab. The aim of this paper is to emphasise on the utility of erosion risk maps forenvironmental protection and agricultural uses.

This paper presents a GIS-based geomorphological map of Milos island. In orderto create this kind of maps, one must employ a wide variety of digital processingtechniques, in order to obtain high accuracy and analysis speed. Both aerial photosand satellite images had to be geometrically and radiometrically corrected, in order to eliminate distortions. Using digital image processing techniques, different information layers were developed and imported to the MapInfo GIS. GIS software was used for the comparative spatial and quantitative analysis of all the information layers. The GIS handled all geomorphological data as separate objects. Thus, everyobject’s attributes and every distance between objects, is easily measurable. Moreover, data modifications and updates are also very quick and easy. Milos is a volcanic Aegean-sea island. Over the last decades, significant geomorphological changes have taken place, because of rapid increment of tourism. The rapid, and of a large scale, geomorphological changes that have already taken place and will continue in the future, were the reason why Milos island was selected among others to be studied from a geomorphological point of view. This paper’s aim is to record geomorphological features of Milos island in order to be compared with data that will be gathered in some years at the second stage of this study, in order to present geomorphological changes due to human activity impacts.

In this article, we will present the ‘Cadastre Grid Software’ (version 3) and its new enchanced functions and capabilities. This new version has already been used on a variety of applications, including archaeology (investigations on cadastre detection), geology (analysis on tectonic fault directions) and geomorphology (drainage system analysis). Moreover, we will describe the use of ‘Cadastre Grid Software’ in combination with MapInfo GIS, in order to extract primary data from maps (topographic, pedological, etc.), aerial photos and satellite images. Cadastre lines and grids extracted using the ‘Cadastre Grid Software’, are then processed with MapInfo GIS, enabling comparisons among different models or study areas, e.g. Bezier’s and Patra’s cadastres.

This study is an attempt of creating a virtual model of Patra’s cadastre grid. For this purpose geomorphological and environmental data in combination to archaeological data were analysed using different information technologies. Different kinds of techniques were used in order to reach the target. Remote Sensing and Digital image processing was used in the first place to initiate the primary data. Geographical Information Systems (G.I.S.) were used for the processing of primary data and the production of secondary information layers.Geomorphological and environmental data were particularly helpful for theelimination of those lines that couldn’t be part of a Roman cadastre grid.

Samos island has recently (July 2000) experienced severe fire events that changedmost of its landcover map. Apart from this catastrophy, Samos island also encounters intense rainfalls, soil erosion and flood events. Unfortunatelly, erosion proccess are highly accelerated when natural protective mechanisms, like landcover, are absent. At Samos case, we produced an erosion risk map, using as principal attributes lithology, drainage system analysis, topography and recent landcover data. All these data, were input into the GIS and processed through fuzzy logic rules, in order to derive an erosion risk map. Such maps can be proved very useful tools, when classifying zones of high erosion risk and when taking appropriate measures in advance. Erosion risk maps can be used from both local authority and research teams that need, among others, to evaluate erosion factor or plan effective policies.

Selecting a suitable area for a sanitary landfill is a very complicated task involvinga series of parameters. For the needs of this paper, we categorized all the parameters into five major groups: a) Geological – Geomorphological – Hydrological - Hydrogeological, b) Land planning, c) Environmental d) Operational and e) Financial. Each group may contain many sub-groups and so on. In this study we attempt to indicate the most suitable areas for the establishment ofa sanitary landfill at Naxos island, using Geographical Information Systems. Themethod of ‘multiple selection criteria’, helps to objectively specify suitable areas,based on given weight factors for each parameter.Geographical Information Systems enabled the processing of all necessaryparameters and weight factors in order to develop different theoretical models forNaxos island. All resulting areas, were automatically marked by the GIS, and the bestpossible solution was isolated. Moreover, we developed different thematic maps,graphically representing the elimination criteria and the resulting positions.

Coastal zone of the Ithaki Island consists mainly of calcareous rocks (>80%) of the Ionian geotectonic zone and secondarily of Neogene sequences, flysch and Quaternary deposits. Due to the presence of carstic limestones, vegetation is poor with the ‘makia’ type of vegetation to cover almost the half of the coastal land. In terms of coast formation, four types of coasts have been identified, according toShepard’s genetic classification; these are coasts of: tectonic origin, terrestrial deposition, subaerial erosion and marine erosion. The small coastal towns and villages occupy only the 3,1% of the coastal land being developed primarily on Quaternary deposits and in areas with small (10%) topographic slope. Beaches suitable for touristic activities are present within protected small bays and usually are associated with the presence of fluvial deposits reworked by the existed wave activity.

The aim of this paper, is to demonstrate the use of GIS technology in the study of knickpoints, by processing geographical, geomorphological and geological variables. The final result is the creation of different level databases and thematic maps and their combination in order to help scientists to deduce geomorphological conclusions. These GIS techniques help the user to locate probable knickpoints fast and accurately, minimizing the subjectivity of the processing. This methodology can be easily applied to any set of similar nature primary data, without any modifications. As a case study we used Leukadaisland (West Greece) because it gathers a variety of lithologies, a sufficient rain state, a polymorphic relief and tectonic activity. The result of this study is a field cross-tested method based on GIS techniques that can predict the exact point providing the coordinates (e.g. Longitute/Latitute) of possible knickpoints. Thedata that the user has to supply to the system is a good scale relief and the drainage system of the area.

Coastal zone of the Ithaki Island consists mainly of calcareous rocks (>80%) of the Ionian geotectonic zone and secondarily of Neogene sequences, flysch and Quaternary deposits. Due to the presence of carstic limestones, vegetation is poor with the ‘makia’ type of vegetation to cover almost the half of the coastal land. In terms of coast formation, four types of coasts have been identified, according to Shepard’s genetic classification; these are coasts of: tectonic origin, terrestrial deposition, subaerial erosion and marine erosion. The small coastal towns and villages occupy only the 3,1% of the coastal land being developed primarily on Quaternary deposits and in areas with small (10%) topographic slope. Beaches suitable for touristic activities are present within protected small bays and usually are associated with the presence of fluvial deposits reworked by the existed wave activity.