Discontinuité d'origine eustatique dans les molasses oligocènes de l'Est du Bassin aquitain (SW France). Apport de la biochronologie

One of the previously mapped discontinuities at the eastern edge of Aquitain molassic basin is shown as the result of an erosive event erasing much of Rupelian molasses, now only preserved as marginal deposits. That event occurring between Rupelian and Chattian is likely to concern the whole basin. The sudden drop of hydrographic base level registered by an erosive magnitude of one hundred meters is only compatible with the sea level drop known during the great Oligocene regression