A Note on the Uranium Mineralisation along Jamual-markundi Fault, Sonbhadra and Sidhi Districts, Uttar Pradesh and Madhya Pradesh

Surface indications of uranium mineralisation associated with ferruginised brecciated rocks is traceable, intermittently, over a strike length of 25 km, exposed along the Jamual -Markundi Fault (JMF), at the tectonic contact of Neo- to Meso-Proterozoic Vindhyan Supergroup and Paleo-Proterozoic Mahakoshal Group between Gurdah and Mohariya, Sonbhadra and Sidhi districts of U.P. and M.P. respectively. Preliminary investigations reveal uranium (U₃O_g) content upto 610 ppm with little or no ThO₂. Uranium occurs in adsorbed state in the ferruginised groundmass of brecciated rock and probably related to hydrothermal activity. This is the first reported uranium occurrence from this unconformity related geological set up in the Son valley.