SEDIMENTOLOGY AND DEPOSITIONAL SETTING OF THE LATE CRETACEOUS FIQA FORMATION IN THE UNITED-ARAB-EMIRATES

In the United Arab Emirates, the Fiqa Formation (Coniacian-middle Maas trichtian) ranges from about 60 to 1220 m (200-4000 ft) in thickness a nd consists of argillaceous limestones, dark grey to grey-brown shares , marls and marry shale with abundant benthonic and planktonic foramin ifera. These sediments were laid down in a shallow to deep open-marine shelf setting. Clay content in the rock ranges up to 60%, and is gene rally higher in the Lower Fiqa (Shargi Member) than in the Upper Fiqa (Arada Member); kaolinite dominates the clay fraction, suggesting rede position of lareritic-weathering deposits formed under alternating ari d and humid climates. The non-clay fraction is dominated by calcite, q uartz and feldspar with traces of dolomite, pyrite, siderite, glauconi te and phosphate. The petroleum source-rock potential of the Fiqa Form ation is generally low, primarily because of a lack of organic maturat ion owing to relatively shallow burial in most areas.