Gold and Base Metals Associated with Uranium Mineralization in some Lower Carboniferous Rock Units at Wadi Abu El Mogheirat area, Southwestern Sinai, Egypt

International audienceThe Lower Carboniferous Sediments at Wadi Abu El Mogheirat comprise four stratigraphic formations, from base: Um Bogma, El Hashash, Magharet El Maiah and Abu Zarab formations. Most-concentrated radioactive anomalies at Wadi Abu El Mogheirat are in the Middle Um Bogma Formation. The gibbsitic marl in this formation shows the highest uranium contents (around 710 ppm). Gibbsitic marl and black gibbsite of the Middle Um Bogma Formation show higher enrichment in Co, Cu, Mn, Ni, Pb, Zn, U, V, Ce and Th. Black gibbsite contains the highest total rare earth elements concentration; especially in terms of LREEs, while gibbsitic marl contains the highest contents of HREEs. Anomalous contents of gold at Wadi Abu El Mogheirat are recorded for the first time in the gibbsitic marl (content: 10.4 ppm), black gibbsite (2.8 ppm) of the middle member of Um Bogma Formation and in the siltstones of El Hashash Formation (0.6 ppm). Gibbsitic marl shows the presence of uranothorite, celestite, zircon, atacamite, barite, xenotime and rutile. These characterizations demonstrate that the middle member of Um Bogma Formation constitutes a potential source for gold. This conclusion is reinforced by the possibility to exploit other metals such as Co, Cu, Mn, Ni, Pb, Zn, U, V, Th and Ce as by-products