Mineralogical and Geochemical Studies on Manganese Deposits at Abu Ghusun Area, South Eastern Desert, Egypt
I. A. Salem, N. H. El-Shibiny, M. Abdel Monsef

The Abu Ghusun manganese deposit is subjected to mineralogical and geochemical studies in order to elucidate its petrogenesis. Manganese occurs as sheets, lenses, encrustation and fracture filling within clastic sediments of the Abu Ghusun Formation of Oligocene age. The mineralogical, and geochemical data confirmed by microscopic investigations, X-ray diffraction (XRD), infrared absorption spectrometry (IR), differential thermal analyses (DTA), thermo gravimetric (TG), environmental scanning electron microscope (ESEM) and chemical analyses of major and trace elements. The results showed that Abu Ghusun manganese deposits include two different ore types: 1- massive ore and 2-manganiferous sandstone ore. The main mineralogical composition of manganese ore types are pyrolusite, psilomelane, rhodochrosite and hematite. The gangue minerals are quartz, feldspar, rock fragments, apatite and calcite. The geochemistry of Abu Ghusunmanganiferous sandstone and massive ore types indicated that they are rich in Cr (60, 58 ppm), Zn (132, 200ppm), Ba (12050, 1414 ppm), Sr (3400, 353 ppm) and V (156, 196 ppm) respectively. The discrimination diagrams based on major and trace elements also indicated that Abu Ghusun manganese deposit is a hydrothermal origin. The manganiferous sand stone (40.9% MnO2) and the massive ore types (48.1 % MnO2) lie in the field of high grade B..

Full Text: PDF     DOI: 10.15640/jges.v4n2a4