Journal of Petroleum Geology, Vol.10,
No.3, pp. 335-350, 1987
©Copyright 2000 Scientific Press,
Ltd.
SEDIMENTARY HISTORY AND
PALEOGEOGRAPHY OF LOWER AND MIDDLE JURASSIC ROCKS, CENTRAL SAUDI
ARABIA
Mohamed A. Moshrif*
* Geology Dept., College of
Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi
Arabia.
Abstract
Eight clastic and carbonate lithofacies of
Lower and Middle Jurassic age (the Marrat and Dhruma Formations
respectively) have been identified. These lithofacies are mainly
shales, shales-and- siltstones, siltstones-and-shales,
sandstones, argillaceous limestones, calcarenitic limestones,
calcarenites and dolomites. Intraclasts, pellets, oolites,
gypsum, algae, and coral reefs were also found to be dominant
among these lithofacies. Furthermore, these beds contained either
restricted or diversified biota, with a few sedimentary
structures such as lamination, cross-bedding and common
bioturbation. Thus, it is presumed that the Lower and Middle
Jurassic rocks in Central Saudi Arabia were deposited in very
shallow (i.e. tidal flat and lagoon), shallow-neritic, and
deep-marine conditions of the Tethys Sea.
