Clarification on the geomorphological evolution and the future of gravel spits of Loc'h de Landevennec (Brittany, France)

During the last ten years, the acquisition of new data at Loc'h de Landevennec coastal site, located in the Bay of Brest (Brittany, France), compiling stratigraphic analysis of sedimentary records, study of old maps, digital processing of aerial photographs and topomorphological monitoring of the foreshore conducted between 2004 and 2012, lead to propose a new interpretation of the formation of this couple of gravel barriers, as well as the morphological evolution of the coastal area at long (103 years), mid- (102 years) and short (101 years) timescales. The results suggest a first cycle of barrier building/destruction from the Early Middle Ages, leading to the spread of a first gravel barrier after severe storms. The same sequence of morphological events is recorded during the last two centuries, emphasising the low resilience of the barrier to stormy events.