Evaluation of the Upper Cretaceous Black Shales: A Case Study from Islam and Hamrawin Phosphate Mines, Qussier Area, Southern Eastern Desert, Egypt

Document Type : Original Article


Prof. of Geochemistry Geological Sciences Dept., National Research Centre, Dokki, Giza, Egypt.


The Campanian-Maastrichtian parent rock of Islam and Hamrawin Mines shale from Qussier was studied from mineralogical and geochemical compositions to deduce its origin, deposition environments, tectonic setting, as well as the economic evolution. XRD patterns indicated that the study black shales are consisted of two phases, clay and non clay minerals. The Duwi Formation implies highly textural maturity. The black shales for Duwi Formation were formed under anoxic shallow marine conditions. The chemical parameters indicated that the study area was deposited under high salinity, warm and humid climate conditions. The high Fe2O3 content, some traces and REEs; Zr, Ba, Nb, Sr, Ce, Th, Y, Hf, and La concentrations as well as ICV and CIW pointed to input of recycling components derived from old sedimentary basis in a comparatively stable tectonic setting. The geochemical data, CIA, CIW and PIA values are revealed that the Duwi Formation black shales are subjected to the intensive chemical weathering either for the original basis or through transportation before deposition. The studied samples are plot in active continental margin of provenance. Black shales of Islam mines are represent the highest average of ΣREEs, ΣLREEs and ΣHREEs (233.75, 125.67 and 41.72ppm; respectively), with respect to the other neighboring mines. Consequently, the ΣREEs are increased to the direction of south Qussier. The chemical composition of black shales for the Duwi Formation had diversity sources for redox-sensitive traces and REEs in the Qussier area. Black shales of Islam and Hamrawin Mines can be classified as high-quality sources for extraction oil and gas.


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