Three-dimensional accommodation analysis of the Keuper of the Paris Basin: discrimination between tectonics, eustasy and sediment supply in the stratigraphic record

During the Keuper, the Paris Basin was an intracratonic sedimentary basin filled by continental deposits. Using paleo-environmental, isopach and paleo-altitude maps, we estimate the variations of accommodation rate at the scale of stratigraphic minor hemi-cycle (1–3 Ma). An analysis of the short- and long-wavelength accommodation variations allows us to assess the relative influence of tectonics, eustasy and sediment supply on the stratigraphic record. Our data suggest a pattern of subsidence along three trends: E–W in the Carnian, E–W to NNE–SSW in the Norian and NE–SW in the Norian–Rhaetian. During the Keuper, the Paris Basin accurately records the different phases of the opening of the Tethys Ocean associated with a rotation of the extension direction. The Norian cycle could thus reflect the intraplate stresses in a transitional period between the Triassic and the Liassic. [Copyright &y& Elsevier]