Stratigraphy and Sedimentation of the Middle Jurassic, U.A.E.
Jose E. De Matos, Gordon M. Walkden, 2000. "Stratigraphy and Sedimentation of the Middle Jurassic, U.A.E.", Middle East Models of Jurassic/Cretaceous Carbonate Systems, Abdulrahman S. Alsharhan, Robert W. Scott
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Wadi Naqab, SE of Ras Al Khaimah in the U.A.E., exposes an 800 m thick, shallow-water, Middle Jurassic succession. The base of the Bajocian is placed at a sequence boundary a t ca. 460 m above the top Triassic and 45 m beneath the horizon that yielded the ammonite Poecilomorphus sp. The Bajocian/Bathonian contact is marked by the highest occurrence of Haurania deserta. The questionable Bathonian/Callovian boundary either coincides with the last occurrence of Alzonella cuvillieri or is near the base of the Trocholina palastiniensis zone. The last occurrence of Kilianina bianchiti indicates the top of the Callovian. A new Bajocian foraminifer, Pseudodictyopsella jurassica, has been identified.
In Wadi Naqab, the Middle Jurassic corresponds to a broadly shallowing succession comprising multiple, meter-scale, fifth-order cycles. The Bajocian is predominantly subtidal, and cycles are commonly terminated by thick, massive oncoidal/peloidal packstones or grainstones. Most of the Bathonian and Callovian cycles start with spicular wackestones and end with cross-bedded peloidal/oolithic grainstones and/or stromatoporoid/coral rudstones. A direct comparison is established between the Middle Jurassic of Wadi Naqab and the subsurface of the Emirates. In the subsurface of Abu Dhabi, the Bajocian Izhara and Bathonian–Callovian Araej formations are the rock units that make up the Middle Jurassic. As a result of regional comparisons performed in this study, the Izhara Formation is redefined and a new type section proposed.
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Middle East Models of Jurassic/Cretaceous Carbonate Systems
This volume will interest tectonic modelers, stratigraphers, sedimentologists, and explorationists. It is the product of the international conference of “Jurassic/Cretaceous Carbonate Platform-Basin Systems, Middle East Models” that was convened in December 1997 jointly by SEPM (Society for Sedimentary Geology) and the United Arab Emirates University in Al Ain, United Arab Emirates. The twenty-three papers present new data and interpretations arranged in three sections: 1) sequence stratigraphy, cyclostratigraphy, chronostratigraphy, and tectonic influences, 2) depositional and diagenetic models of carbonate platforms, and 3) hydrocarbon habitat and exploration/development case studies. New tectonic models of the Arabian Basin, new stratigraphic and sequence stratigraphic reference sections, new geochemical and source rock data, and new reservoir data are presented. New geologic models make this set of papers relevant to geoscientists working outside of Arabia also.