Sedimentary markers in the Provençal Basin (western Mediterranean): A window into deep geodynamic processes

Abstract

Deep Earth dynamics impact so strongly on surface geological processes that we can use sediment palaeo-markers as a window into the deeper Earth. Derived from climatic and tectonic erosive actions on the continents, and related to eustasy, subsidence and isostasy, the sediment in a deep basin is the main recorder of these processes. Nevertheless, defining and quantifying the relative roles of parameters that interact to give the final sedimentary architecture is not a simple task. Using a 3D-grid of seismic and wide-angle data, boreholes and numerical stratigraphic modelling, we propose here a quantification of post-rift vertical movements in the Provençal Basin (West Mediterranean) involving three domains of subsidence: seaward tilting on the platform and the slope and purely vertical subsidence in the deep basin. These domains fit the deeper crustal domains highlighted by previous geophysical data. Post-break-up sedimentary markers may therefore be used to identify the initial hinge lines of the rifting phase and the subsidence laws.