Marine Geology | 2019
Correlating three centuries of historical and geological data for the marine deposit reconstruction of two depositional environments of the French Atlantic coast
Abstract
This paper details a high-resolution record of French Atlantic coast extreme wave events using a multi-proxy analysis of dated sedimentary deposits. Two lagoons 1) the Petite Mer de Gâvres and 2) the Traicts du Croisic were chosen to identify damaging storm events from the last 300\u202fyears with Beeker sampling, 210Pb and 137Cs dating and sedimentary analysis. Using two new geochemical proxies in the French Atlantic coast, Sr/Fe and Ca/Ti, shows that several storminess events are reported in the nine cores drilled. By correlation with historical archives, seven major storms are confirmed: 1924\u202fCE, 1940\u202fCE, 1972\u202fCE, 1977\u202fCE, 1990\u202fCE, 1999\u202fCE, and an 1896\u202fCE highly damaging event. Four other XIXth and XVIIIth century extreme wave event correlations are also proposed from this multi-proxy analysis: 1775\u202fCE, 1811\u202fCE, 1838\u202fCE and 1876\u202fCE. Societal and natural impacts caused by these coastal floods are revealed using our dense and varied historical archives.