Evolution of Upper Triassic Fluvial Systems Across North West Africa; the Interplay of Local Versus Regional Drainage Systems

Abstract

The Middle to Upper Triassic “TAG-I” sandstones were deposited in a series of intra- and pericratonic basins that developed after the Hercynian orogeny on the Saharan Platform margin. They form a broad facies belt of continental clastics that extend from Morocco to Egypt. Recent wells drilled in Eastern Morocco have proven economic gas flow rates from Late Triassic continental sandstones—sourced from Palaeozoic shales and trapped with post-Hercynian rift structures. The play bears many similarities to the prolific TAG-I play in the Berkine Basin and offers potential for extension of this petroleum system farther west into Morocco. Reservoir quality and thickness is a key uncertainty, and better understanding of the depositional systems and provenance is critical to reducing uncertainty and predicting where the sandstones offer viable exploration target.