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International audience; Borehole CDB1 (675.05 m) crosses the deepest Cenozoic sedimentary basin of the Armorican Massif, the Rennes Basin, to reach the underlying basement at a depth of 404.92 m, made up of the Late Neoproterozoic to Early Cambrian Brioverian Group, weathered down to 520 m depth. The basin's Cenozoic deposits are divided into seven formations, ranging from Early–Middle Bartonian to Late Pliocene in age. Coastal sediments at the very base, along with a thick Priabonian lacustrine episode, imply a major revision of the regional palaeogeography, whilst a very steady and low-energy lacustrine-palustrine environment throughout the Priabonian and Early Rupelian argue for an aggradational system associated with uniform subsidence. Palynological assemblages attest to environmental and climatic changes through the Eocene and Early Oligocene, in accordance with regional and global trends (Eocene–Oligocene Transition).

International audience; The uppermost Cretaceous to early Palaeogene is a period of major deformations of the western part of the Eurasian plate with prominent basin inversions starting from the Coniacian onwards. These deformations occur in a complex geodynamic setting within both the context of the Africa-Eurasia convergence and the North Atlantic opening. While Mesozoic graben inversions have been extensively studied, particularly in Eastern Europe and the North Sea, more gentle deformations that affect thicker crust areas (intracratonic basins and emerged lands) are not as well documented. The objective of this study is to constrain the exact timing, type and magnitude of the early Palaeogene deformations affecting the intracratonic Paris basin and to integrate them at the Western European scale. Relatively gentle deformations are attempted through a high-resolution reconstitution of its stratigraphic record based on outcrops and well-dated wells, and a high number of well-logs that are correlated using the "stacking pattern" sequence stratigraphic technique. Two orders of sequences are identified (third- and fourth-order) and correlated throughout the basin. Basin geometric and palaeogeographic reconstitutions are based on sediment thickness and facies analysis. Two-dimensional accommodation space measurements were taken in order to quantify the magnitude of the deformations. Three phases of deformation were recognized. 1. An intra-Maastrichtian-pre-Thanetian (59 Ma) deformation, with major uplift and erosion of the Cretaceous strata with two sub-periods of deformation: Maastrichtian-pre-middle-Danian and Upper Danian-pre-Thanetian long wavelength deformations. This period of major deformation is coeval with Upper Cretaceous-pre-Danian compressive deformations linked to the Africa-Eurasia convergence in southern France and with volcanic activity from the North Atlantic to Massif Central and the Rhenish Shield during the Palaeocene; 2. an early Ypresian (55.1-54.3 Ma) medium wavelength deformation (× 10 km), here reported to be a stress rearrangement related to the onset of the North Atlantic opening; 3. an uppermost Ypresian (49.8 Ma) long wavelength deformation (× 100 km), contemporaneous with flexural compressive deformations in the Aquitaine Basin (Pyrenean deformation), and related to the Iberia-Eurasia convergence.

For the first time the Carnivora and the Perissodactyla from Aubenas-les-Alpes are studied. Five taxa are identified: two Carnivora, Nimravus intermedius and a medium-sized species of amphicyonid and three Perissodactyla Ronzotherium romani , Molassitherium albigense and Cadurcotherium cayluxi . The microflora shows a subtropical to Mediterranean climate with a marked dry season and indicates an age near the Rupelian-Chattian boundary for the site.