Geochemical modelling for the unconformity-related uranium mineralization. A case study from Baskati area, Madhya Pradesh, India

Signatures of concealed unconformity-related uranium mineralization at the contact of Chhotanagpur Granite Gneissic Complex (CGGC)/Mahakoshal and Lower Vindhyan Semri sequence have come to light at Baskati, in Vindhyan-Mahakoshal Basin, following a multiprolonged exploratory efforts. Systematic lithogeochemical sampling brought out uranium halos with concentration sufficiently above the normal background along reactivated faults/fractures occurring parallel and oblique to the unconformity contact. Alteration features like haematitization, chloritization and illitization have also been observed in surroundings of these reactivated faults/fractures. Geochemical modelling indicates a hypogene source for mineralizing fluids. Based on geochemical modelling supported by geology, structure and lithogeochemistry, unconformity-related U mineralization model has been envisaged and the target area has been narrowed down for sub-surface exploration. (author)