<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>10</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Saitis, G.</style></author><author><style face="normal" font="default" size="100%">Koutsopoulou, E.</style></author><author><style face="normal" font="default" size="100%">Evelpidou, N.</style></author><author><style face="normal" font="default" size="100%">Kawasaki, S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A comparative study of beachrock mechanism formation focusing on natural and artificial beachrocks: case of Diolkos, Corinth, Greece and Sumuide, Okinawa, Japan</style></title><secondary-title><style face="normal" font="default" size="100%">RCG2019 “Geomorphology of Climatically and Tectonically Sensitive Areas”</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2019</style></year></dates><pub-location><style face="normal" font="default" size="100%">Athens - Greece</style></pub-location><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;div&gt;Beachrocks are a window in the past environmental, geological, sedimentological and&amp;nbsp;geographical conditions that were dominant on the coastal zone. The minerochemical&amp;nbsp;examination of cement and the sedimentological analysis are the most efficient methods for&amp;nbsp;understanding the formation mechanism. However, the examination of beachrock samples&amp;nbsp;have limitations and the evidence of formation mechanism are not enough. This study&amp;nbsp;emphasizes on the beachrock formation mechanism through the comparison of cement&amp;nbsp;characteristics, mineral chemistry and sedimentology of beachrock occurrences from different&amp;nbsp;geological and geographical setting areas Diolkos, Corinth, Greece and Sumuide, Okinawa,&amp;nbsp;Japan. Furthermore, in order to investigate the beachrock formation, artificial beachrock&amp;nbsp;samples were created in-vitro using sand samples and ureolytic bacteria from Okinawa under&amp;nbsp;accelerating conditions. Bulk samples were collected from the study areas in order to analyze&amp;nbsp;their mineralogical (XRD and SEM-EDS) and chemical (XRF) composition. Microscopy&amp;nbsp;studies (optical and SEM-EDS) revealed that the cement agent from Diolkos is mainly&amp;nbsp;composed of High-Magnesian Calcite (HMC) in comparison to the Sumuide beachrock which&amp;nbsp;is characterized by the presence of calcite and aragonite. Additionally, the analysis revealed&amp;nbsp;clastic silicate and aluminosilicate minerals. The grain composition of Diolkos slab consists of&lt;/div&gt;
&lt;div&gt;quartz, plagioclase, K-feldspar with 20% bioclasts compared to the Sumuide beachrock&amp;nbsp;grains that consist of calcareous residuals from the local coral reef. The artificial beachrock&amp;nbsp;investigation indicated that ureolytic bacteria that reside in the Sumuide beach sediment, are&amp;nbsp;capable to precipitate aragonite coating the sediment grains and filing the pores. The&amp;nbsp;cementation was most active in the top part of the samples than the bottom part. This is an&amp;nbsp;indicator that the beachrock formation might occur in depths were these bacteria can be&amp;nbsp;found. The artificial beachrock analysis included its physicochemical parameters using UCS&lt;/div&gt;
&lt;div&gt;penetration, pH and Ca&lt;sup&gt;2+&lt;/sup&gt; measurements, X-Ray CT-scanning, petro-graphic polarized&amp;nbsp;microscopy, XRD, and SEM-EDS.&lt;/div&gt;</style></abstract></record></records></xml>