SEDIMENTATION-RATE IN THE THAU BASIN (FRA NCE) ACCORDING TO GEOCHRONOLOGICAL, GEOCHEMICAL AND STRATIGRAPHICAL DATA

Geochronological data (Pb-210) Obtained on four sediment cores, couple d with geochemical analysis, X-ray radiography, meteorological data an d stratigraphical observations, made it possible to provide a recent a nd coherent sedimentary history of the Thau basin (Herault, France). C luster analysis of major elements isolates some horizons presenting a strong terrigenous signature, which are also identified by X-ray. Thes e strata, characterized by high Al, Fe, Ti and K contents, are the con sequence of the exceptional flood which occurred in September 1875. Th is event serves to calibrate the radiochronological data, which are li mited at 100 years. Cores located close to the continental and fluviat ile inputs accurately record the flood horizon. Measured sedimentation rates range between 0.09 and 0.18 g.cm(-2).yr(-1) and are in general agreement with the knowledge concerning the dynamic of the basin.