The structural setting and palaeogeographical evolution of the Grès d'Annot Basin
Gillian Apps, Frank Peel, Trevor Elliott, 2004. "The structural setting and palaeogeographical evolution of the Grès d'Annot Basin", Deep-Water Sedimentation in the Alpine Basin of SE France: New perspectives on the Grès d'Annot and related systems, P. Joseph, S. A. Lomas
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A new kinematic model is derived for part of Haute Provence, which recognizes that Alpine deformation, involving both the Mesozoic and sub-Mesozoic section, has been active since the onset of Tertiary deposition. This model places the Grès d'Annot basin in an overall compressional setting, dominated by SW-directed Alpine thrusting, during deposition of the Tertiary basin fill sequence. Evidence is presented that one block of Palaeozoic material (Barrot) was strongly uplifted and deeply eroded prior to the onset of Tertiary deposition in the area. Local thin-skinned extension and strike-slip are observed, but these are secondary components, which are interpreted to be part of the overall thrust system. The region was affected by three different orogenic events. Pyreneo-Provençale thrusting established a structural fabric that influenced later, syndepositional thrust geometries. The Late Eocene to Early Oligocene Grès d'Annot Basin was a structured foreland basin created by the loading effects of the Alpine orogeny. The supply of siliciclastic sediment to the basin was controlled by tectonic events far to the south, in a subduction-related orogeny that extended from East Iberia to SE France. SW-directed Alpine compression within the basin produced significant basin-floor topography, which developed immediately prior to, and during, the Nummulitic transgression. The evolving palaeo-relief of the basin is recorded in thickness and facies variations of the older Tertiary lithostratigraphical units (Poudingues d’Argens, Calcaires Nummulitiques and Marnes Bleues), and by the onlap geometry of the Grès d'Annot turbidites. This allows us to define a set of palaeogeographical maps of the basin throughout its evolution, linked to a set of sequentially restored structural sections. This basin floor topography was complex, because Alpine thrusting overlapped the older east-west striking structures, and it created a set of partially isolated sub-basins. Major early compressional structures partitioned the basin, exerting strong control on all the Tertiary depositional systems, including the Grès d'Annot turbidite systems.
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Deep-Water Sedimentation in the Alpine Basin of SE France: New perspectives on the Grès d'Annot and related systems
The Grès d′Annot Formation of SE France constitutes a classic and outstanding example of a sand-rich turbidite system controlled by synsedimentary tectonics, and has often been used as an outcrop analogue for deep-water hydrocarbon reservoirs. Over the last 10 years, research efforts by different academic and industrial teams have led to important reappraisals of prevailing ideas on the Gres d′Annot, particularly on the nature and controlling factors of the depositional processes, the small-scale architecture and sequence organization of the deposits, the tectonic regime of the basin and its impact on palaeogeography, and the interaction between sediment gravity flows and basin-floor topography.
This volume offers a multidisciplinary overview and draws up the ′state-of-the-art′ of scientific knowledge on this influential turbidite system. Complementary aspects are covered, from structural geology, sedimentology and sequence stratigraphy, to modelling of sedimentary processes and architectures, geochemistry, reservoir characterization, seismic modelling and uses as analogues for deep-marine hydrocarbon fields.
This book will be of use to both academic researchers (geologists and geophysicists) and industry professionals dealing with the characterization and modelling of deep-water sediments.