<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pirazzoli, P.</style></author><author><style face="normal" font="default" size="100%">Evelpidou, N.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tidal notches: a sea-level indicator of uncertain archival thrustworthiness.</style></title><secondary-title><style face="normal" font="default" size="100%">SLALOM International Conference</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;div&gt;Tidal notches are known to undercut limestone rock formations in the mid-littoral zone, especially in microtidal&amp;nbsp;marine areas. Fossil tidal notches in uplifted or submerged positions have often been used to deduce former sealevel&amp;nbsp;stands and tectonic movements. In particular, the good preservation of a tidal notch profile after emergence&amp;nbsp;or submergence may be used as excellent evidence that the relative sea-level change was rapid, possibly coseismic.&amp;nbsp;Tidal notches are believed to result mainly from marine bioerosion processes during periods of stable relative&amp;nbsp;sea level. While in tropical environments their development may often include bioconstruction layers near the&amp;nbsp;notch base, in temperate environment they tend to be purely erosional features, mainly caused by the boring&amp;nbsp;capacity of endolithic and epilithic algae and by the grazing gastropods that rasp away the microflora together with&amp;nbsp;rock particles in the intertidal range.&lt;/div&gt;
&lt;div&gt;Micro-erosion measurements have shown that the rate of deepening of a tidal-notch profile may be very&amp;nbsp;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&amp;nbsp;of the Mediterranean). This high variability may depend from seasonal changes in the environment (temperature,&amp;nbsp;salinity, air pressure) that have an influence not only on intertidal vegetation and grazing organism, but also on&amp;nbsp;sea-level changes over seasonal or inter-annual scales. In spite of this variability, the inward depth of fossil&amp;nbsp;notches may be used as an approximate method to roughly estimate the duration of a period of relative sea-level&amp;nbsp;stability.&amp;nbsp;All carbonate rocks are not equally sensitive to tidal-notch development: the slope of the rock layers and&amp;nbsp;irregularities on the rock structure or surface may locally prevent the development of a tidal notch. This means that&amp;nbsp;tidal notches may be present in some locations but not at some nearby sites. Therefore the absence of tidal&lt;/div&gt;
&lt;div&gt;notches can hardly be used as a reliable criterion to interpret the lack of a sea-level stillstand. During the last two&amp;nbsp;centuries tide gauges have shown that the global sea level was rising at a rate faster than the possibilities of&amp;nbsp;bioerosion. As a consequence, new tidal notches have not been forming in most places during the last couple of&amp;nbsp;centuries. This is causing a general lacuna in geologic marks.&lt;/div&gt;
&lt;div&gt;In conclusion fossil tidal notches can be useful to interpret relative sea-level change in places where they are&amp;nbsp;preserved. However, the lack of tidal notches does not provide evidence of the absence of a sea-level stillstand&amp;nbsp;and coastal geomorphic archives are most often incomplete.&lt;/div&gt;</style></abstract></record></records></xml>