Role of Structural Heritage and Global Tectonics Events in Evolution of Algerian Triassic Basin: Tectonic Inversion and Reservoir Distribution

A. Boudjema, P. Tremolieres

Fieldwork and subsurface studies (350 bore holes and more than 100 seismic profiles) show the structural evolution of the Triassic Saharian basin.

This evolution is controlled by the successive motions of ancient faults of the Paleozoic basement during the different compressional and distensional tectonic phases. These movements led to some tectonic inversions. Depending on the strike of the faults, the present results correspond to normal throw or reverse throw at the level of hydrocarbon reservoirs.

These tectonic phases clearly result from relative motions between African, American, and European lithospheric plates. The Triassic basin, a mobile zone between two rigid shields, constitutes a very good indication of the successive motions.

The distribution and the nature of hydrocarbon fields are clearly related to the proximity of the faults, the post-tectonic erosion of a part of the source rocks, the burial and maturation of the organic matter, and the age of structural traps.

AAPG Search and Discovery Article #91030©1988 AAPG Annual Convention, Houston, Texas, 20-23 March 1988.