Techtonic setting and provenance of Cretaceous and Quaternary clastic sediments,
Eastern Desert, Egypt: Treatise through computatinal sedimentology
Abbas M. Mansour
Geology Dept., Fac. Sciences, South Valley Univ., 83511 Qena, Egypt |
Mineral and chemical compositions of 72 clastic samples from the Eastern Desert, Egypt,
supported by statistical methods give fair evidence to the tectonic setting of depocenters
and the nature of the crust of the provenance region. Cretaeous Nubian Sandstone and
Quaternary Qena sand suites, highly recycled in nature, were dominantly derived from older
sedimentary and metamorphic rocks. They were deposited in a passive marginal basin close
to an orogenic belt of thickened crust. Quaternary coastal sediment suites were deposited
on an active continental margin adjacent to an uplifted Basement, of a mixtitre of
granite-gneisses and siliceous volcanics. Quaternary coastal sediments of different areas
cannot be distinguished from each other on the bases of mineral and chemical
characteristics due to the similar tectonic control of their composition. Quaternary
sediment suites of central Eastern Desert were derived from ultramafic rocks and
calc-alkaline andesitic rocks of magmatic arcs. They reflect the continental island arc
setting or oceanic island arc setting of the provenance region.
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