Corrélations chimiostratigraphiques entre domaines marin et continental : application à une série du Miocène inférieur (Beynes-Châteauredon, Alpes-de-Haute-Provence, France)

Abstract

Abstract The paucity of biostratigraphic information makes the stratigraphic attribution of continental series difficult to establish. To compensate for this lack of data we developed a chemostratigraphic analysis on Lower Miocene series (Alpes-de-Haute-Provence), based on the δ13C isotopic composition of the pedogenic carbonate glaebules preserved in the paleosols. The curve obtained proved to be an excellent tool: 1) at a regional scale, to correlate continental sections that show rapid lateral facies variations over a distance of nearly 10 km; 2) at a global scale, to correlate the fluctuations of the δ13C signal of the continental series with those of the marine realm, thus providing an excellent stratigraphic framework with a time resolution in the range of a hundred thousand years. The results obtained give an Aquitanian age to the first two thirds of the studied series and a Burdigalian age to the upper part. They also provide interesting results on the evolution of the vegetation in response to the Aquitanian marine transgression.