MASSET, J., MICHEL LE VOT*, and A. VILLIEN, Elf Aquitaine Production, Boussens, France

ABSTRACT: Structure and Prospects of Alpine Basins and Foredeep, Aquataine Basin: Exploration in the Foreland of an Alpine Fold and Thrust Belt

The Aquitaine basin lies in the immediate foreland of the Pyrenean fold and thrust belt. As a result, the area shows a very complex structural setting, because inherited structures dating back from the Hercynian are reactivated by the Early Cretaceous extension and later on by the compressive episodes of the Pyrenean orogeny. In this context, the traps for the fields (tilted blocks) are linked to inherited structures and results from a complex history of Early Cretaceous extension and basin subsidence, both northward and southward.

The area shows an almost complete stratigraphic record, extending from the Precambrian crystalline basement to the Tertiary. The main reservoirs are located within Barremian to Kimmeridgian dolomites below 3000 m, where average matrix porosities are low (3-5%), with highly fractured zones allowing excellent production. The main source rocks are also Kimmeridgian to Barremian. The seals correspond to Albian-Aptian shales and shaly limestones.

The Aquitaine basin has a complex history, both structurally and stratigraphically. Therefore, knowledge of tectono-sedimentary units of inherited features related to Early Cretaceous extension is fundamental for petroleum exploration.

AAPG Search and Discovery Article #90990©1993 AAPG International Conference and Exhibition, The Hague, Netherlands, October 17-20, 1993.