| Summary: | International audience The late Cretaceous to early Paleogene is a period of major deformations of the western part of the Eurasian plateknown as the Laramide deformations. These are correlated with major paleogeographic changes - widespreadupper Cretaceous marine platforms (chalk) are uplifted, intensively eroded and announced the present-dayconfiguration of the geology of north-western Europe.These deformations occur in a complex geodynamic setting within both the context of the Africa-Eurasiaconvergence and the North Atlantic opening. Two main mechanisms are proposed: (1) surface upwelling causedby flows in the underlying mantle (Iceland Plume upwelling); (2) horizontal lithospheric deformations (Africa/Eurasia convergence).The precise ages of these deformations and the type of reliefs created (height, wavelength etc.) are still poorlyknown. Here we link onshore landforms (planation surfaces and incised valleys) located on outcrops of Proterozoicto Paleozoic basement (Armorican Massif, French Massif Central) to onshore-offshore sediment accumulationareas (Aquitanian, Paris, Western Approaches, London, Belgium, North-Sea Basins). The aim is to propose atopographic reconstitution of the reliefs and basins of western Europe - for the uppermost Cretaceous to thePaleogene period - performing restored european scale cross sections (geomorphology and geology).This study is based on two different approaches:- Erosional domain - on the mapping and chronology of all the macroforms (weathering surfaces and associatedalterites, pediments and pediplains, incised rivers) dated by intersection with the few preserved sediments,weathering and the volcanics.- Depositional domain - on a more classical dataset of seismic lines and wells, coupled with biostratigraphicrevaluations (characterization and dating of vertical movements of the basins).This work is founded and carried out in the framework of the BRGM-TOTAL project Source-to-Sink.
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