Potentiality of uranium mineralisation along NE-SW trending Sivarampuram-Nutanakalva fracture zone in basement granitoids, Kadapa district, Andhra Pradesh, India Goswami Sukanta1,*, Tiwari Ravi Prakash1, Maurya Vinod Kumar1, Natarajan V.1, Saravanan B.1, Bhatt A.K.1, Verma M.B.2 1Atomic Minerals Directorate for Exploration and Research, Bangalore 2Atomic Minerals Directorate for Exploration and Research, Hyderabad *E-mail: sukantagoswami.amd@gov.in
Online published on 13 February, 2019. Abstract The basement complex in the south of Cuddapah basin consists of granite gneiss and patches of greenstone belts are traversed by number of fractures trending along E-W, N-S NW-SW and NW-SE directions, which are subsequently intruded by younger basic intrusives. Several uranium occurrences are reported along the younger NE-SW trending fracture zone at Kamaguttapalle-Kammapalle area with continuity of correlatable mineralization for over 200m along the strike and up to a vertical depth of 200m. Further 16 km SE of above mentioned fracture, another sympathetic fracture along Sivaramapuram –Nutanakalva area has been identified which extends over a plan width of 1 to 1.5km and length of 15 km. The area exhibits structural complexity due to tectonic and metamorphic modifications of original features. Regional schistosity and gneissosity trend along N-S to NNW-SSE directions. Geochemical exploration along Sivarampuram-Nutanakalva fracture zone has indicated anomalous concentration of hydro-uranium in water samples ranging from 100 to 19,434 ppb U (n=110). The imprints of this fracture zone are noticed close to the basin margin and even traversing the overlying Nagari quartzite indicating post Cuddapah reactivation. The radioactive anomalies of Sivarampuram in fractured basic dyke [0.13 and 0.19% U3O8(β/γ; n=2)] and Katramuduku in fracture granite [0.014 to 0.135% U3O8 (β/γ; n=3)] located along this fracture zone are significant. These surface anomalies vis a vis the hydro uranium anomalies along the NE-SW trending fracture make this zone a potential target for further exploration. Top Keywords Cuddapah basin, Uranium mineralization, Fracture, Andhra Pradesh. Top |