Evolution of the Rhône delta coast since the end of the 19th century / Cinématique du littoral du delta du Rhône depuis la fin du XIXe siècle

Abstract

Abstract The evolution of the Rhône delta coast is analysed using digitally processed data obtained from field surveys effected in 1895, aerial photographs taken in 1940, 1950, 1960, 1970, 1980 and 1990, and a DGPS-based survey carried out in 2000. The whole dataset was integrated into a Geographic Information System to determine coastline retreat and advance and to quantify gains and losses of land area at the coastal fringe of the delta. It is shown that sediment input from the Rhône, longshore drift currents and sea defences have had a marked influence on space-time variations of the position of the coastline. These data enable characterisation of the morphose- dimentary circulation at the coast, and the identification of a clear pattern of littoral sediment cells.