ABSTRACT: Sedimentology of the Sbaa Oil Reservoir in the Timimoun Basin (S. Algeria)
In 1980 oil was discovered in the Timimoun portion of the Sbaa depression in Southern Algeria. Until that time this basin had produced only dry gas.
Since the 1980 oil discovery, several wells have been drilled. Data acquired from these wells were analyzed and are presented in this study.
The oil reservoir is located within a sandstone interval of the Sbaa formation which has an average thickness of 75 m. The Sbaa lies between the Tournaisian (Lower Carboniferous) silts and the Strunian (uppermost Devonian) shales and sandstones.
The sedimentological study reveals that the Sbaa formation contains bimodal facies consisting of coarse siltstones and fine sandstones. The sequence has been attributed to a deltaic environment developed in the central part of the Ahnet basin. The sources of the associated fluvial system are from the surrounding In-Semmen, Tinessourine, and Arak-Foum-Belrem paleohighs.
Thermoluminescence indicates the provenance for the Sbaa sands was the crystalline basement, Cambrian and Ordovician sections.
AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990