Mineralogy and geochemistry of the mesozoic-tertiary subsurface sediments along bardawil lake, North Sinai, Egypt

الملخص EN

An attempt is made in the ptesent work to elucidate the mineralogy and geochemistry of the subsurface sediments in three deep wells drilled around lake Bardawil namely: Malha-1, El-Mazar-1 and Bar-dawil-1-1 in north Sinai.

X-ray diffraction analysis has been used to determine the bulk mineral content in 51 raw powdered samples of shale and limestone, ft was found that kaolinite is dominant in Jurassic and Cretaceous deposits of El-Mazar" well and in the Cretaceous deposits of Malha well.

They have been formed during a period with warm climate and lowered sea level.

While illite seems to be dominant in Jurassic deposits of Malha well indicating a tectonically unstable active area.

The oligocene, Miocene and ?liocene deposits of El-Mazar and Bardawil wells are characterized by dominance of montmorillo-nite and subordinate kaolinite, chlorite and illite revealing a humid climate with little changes.

Source rocks and paleogeography are discussed.

X-ray fluorescence analysis has been carried out on the same raw samples of shale and limestone in order to determine the trace element content.

The stratigraphie distribution of the trace element proved that Ba, Zr, Sr and Pb occur in higher concentrations in Jurassic and Cretaceous deposits of El-Mazar well, while Co, Cr, Cu, V, Pb and Ce are enriched in Pliocene and Pleistocene sediments.

Seven geochemical stratigraphie units (chemozones) are distinguished in El-Mazar well.