High-resolution onshore–offshore morpho-bathymetric records of modern chalk and granitic shore platforms in NW France

Anne Duperret, Céline Raimbault, Bernard Le Gall, Christine Authemayou, Brigitte van Vliet-Lanoë, Vincent Regard, Elsa Dromelet, Sara Vandycke
2016 Comptes rendus Geoscience  
et al.. High-resolution onshore-offshore morpho-bathymetric records of modern chalk and granitic shore platforms in NW France. Comptes Rendus Géoscience, Elsevier Masson, 2016, 348, pp. A B S T R A C T Modern shore platforms developed on rocky coasts are key areas for understanding coastal erosion processes during the Holocene. This contribution offers a detailed picture of two contrasted shore-platform systems, based on new high-resolution shallow-water bathymetry, further coupled with aerial
more » ... oupled with aerial LiDAR topography. Merged land-sea digital elevation models were achieved on two distinct types of rocky coasts along the eastern English Channel in France (Picardy and Upper-Normandy: PUN) and in a NE Atlantic area (SW Brittany: SWB) in NW France. About the PUN case, submarine steps, identified as paleo-shorelines, parallel the actual coastline. Coastal erosive processes appear to be continuous and regular through time, since mid-Holocene at least. In SWB, there is a discrepancy between contemporary coastline orientation and a continuous step extending from inland to offshore, identified as a paleo-shoreline. This illustrates a polyphased and inherited shore platform edification, mainly controlled by tectonic processes. ß 2015 Acadé mie des sciences. Published by Elsevier Masson SAS. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/). § Special session on coastal dynamics, from ASF2013 Paris.
doi:10.1016/j.crte.2015.06.005 fatcat:ehjer5ajtjglrixubn2e6znwai