Location of the study area and extent of the onshore basins and main fault systems of southeastern France during the late Eocene − early Oligocene, after Semmani et al. (2023). In blue, extent of upper Eocene − lower Oligocene sedimentary deposits of ECRIS basins and the Alpine Sea: VaB (Valence Basin), AlB (Alès Basin), SB (Sommières Basin), ViB (Vistrenque Basin), CB (Carpentras Basin), ManB (Manosque Basin), AiB (Aix Basin) and MarB (Marseille Basin). Main fault systems are displayed by black lines: CeF (Cévennes Fault), NF (Nimes Fault), CaF (Cavaillon Fault), MDF (Middle Durance Fault). The location of Fig. 2 is displayed by a red dotted square; the Apt Basin is a sub-basin of the Manosque Basin.