Temporal evolution and internal architecture of an estuary-type sand ridge:: The Longe de Boyard along the French Atlantic Coast

The evolution and the internal architecture of an estuary type sand ridge has been studied with a set of bathymetric data recorded during the last two centuries and with a dense grid of recent very high resolution seismic profiles. Bathymetric data of the so-called, Longe de Boyard sand ridge, displays sand losts due to wave and tide erosion. Internal geometry, through seismic profile analysis, indicates two main phases of deposition recording both, a recent high energy environment and an older low energy one, respectively. Such an evolution is believed to record changes in sedimentation processes mainly related to the end of the Holocene transgression (8 000-5 000 yr BP). (C) 2002 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.