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The Central Region was set up at Nagpur during 1958 initially as Western Circle and subsequently divided during 1984 into Western Region-I with headquarter at Nagpur and Western Region-II with headquarter at Baroda (now Vadodara). With the closure of Western Region-II at Vadodara, the Region was subsequently renamed as Central Region during 1994. Presently, the Region has its own office-cum-laboratory complex and residential quarters at Nagpur, catering to the investigations for uranium, rare metals and rare earths in Chhattisgarh,Maharashtra and in parts of Madhya Pradesh,Uttar Pradesh and Odishastates.
The geological domains of the Central Region are characterized by diverse geology and tectonic settings, comprising extensive Precambrian cratons, Proterozoic Basins & mobile belts, Mesozoic-Cenozoic sedimentary basins and Cretaceous-Tertiary Deccan Trap. These geological domains are known to host a variety of mineral resources. The Archaean-Paleoproterozoic basement comprise of Archean Greenstone belts (>2.5 b.y.), Archean-PalaeoproterozoicUnclassified Crystallines (2.8-2.0 b.y.), Proterozoic granitoids (2.2-2.5 b.y.) and bounded by rift zones/ mobile belts. The high-grade Proterozoic mobile belts (amphibolite to granulite facies) extend from eastern Madhya Pradesh to Chhotanagpur Plateau. Other groups of Lower Proterozoic rocks represent highly deformed volcano sedimentary sequences. Proterozoic Supracrustal belts of Kotri-Dongargarh Supergroup, Sakoli Group,Betul Group,Sausar Group and Sonakhan Group located on the west central part of Bastarcraton and Mahakoshal Group form important tectono-metamorphic units. Middle to Upper Proterozoic platformal sedimentary basins formed in continental anorogenic environment related to extensional tectonic regime forming Abujhmar, Khairagarh, Indravati, Chhattisgarh, Vindhyan, Khariar, Ampani and Pakhal basins. The Palaeozoic-Mesozoic Gondwana sediments deposited in intracratonic-rifted basins occupy large parts of Central Region in Satpudaand Son-Mahanadi basin, Pranhita-Godavari basin etc. The Mesozoic Deccan traps cover nearly 60% of the area under the Region.
Four (04) small metamorphite type uranium deposits at Bodal,Bhandaritola in Kotri-Dongargarh Belt, Jajawal, Dumath-Dhabi localities in Chhotanagpur Granite Gneiss Complex (CGGC) and several other occurrences are confined to these Proterozoic supracrustalsand mobile belts. Besides, several granite related migmatite-hosted and shear-controlled metamorphitetype uranium occurrences have been located within the CGGC domain viz. at Naniyagarh, Kudar-Baran, Jhapar, Jaljalia, Kurludih, Ucherua, Pasaritola, and Piparpan; Central Surguja Shear Zone at Devri, Jhor-Jhirhat, and Kansisot; and in the Tan Shear Zone at Chordhawa, Ghatbahra-Murmur, and Sapalwa.
Proterozoic basins extensively developed in Central India holds significant potential for unconformity type uranium deposits. Integrated exploration techniques, combined with litho-structural, geophysical, and geochemical approaches have helped in locating several uranium occurrences at Chitakhol,Juba-Bajapalli&Dumdama-Dullapalli (Chhattisgarh Basin), Baskati-Paniha&Kusumhar-Kubri (Vindhyan Basin), Nalpani (Khairagarh Basin) and Silekjhodi-Sirisguda (Indravati Basin).
A promising, albeit small, Proterozoic sandstone-type deposit was confirmed in the Moggra area of Maharashtra.Occurrence of volcanic-related uranium mineralisation has been delineated in the Bijepar-Kolarbhatti areas in in Khairagarh Basin (Dongargarh-Kotri Belt).
Investigations in the Gondwana basins have resulted in locating uranium occurrences at few places e.g. Polapathar, Mansinghpura, Kachhar-Dharangmau area (Betul district, Madhya Pradesh). Sub-surface exploration has demarcated small lenses of sandstone hosted uranium mineralization controlled by NNW-SSE palaeo-channels in Motur Formation at KachharDharangmau area in the Satpura-Gondwana Basin. Besides, uraniferous anomalies have also been noted in the Infratrappeans of Lalbarra, Salburdy and Bagh beds.
Rare Metal and Rare Earth Elements Investigations led to establishing columbite- tantalite in pegmatites and associated gravel zones in North Odisha Mobile Belt, Bastar-Malkangiri Pegmatite Belt and CGGC. A significant resource of xenotime bearing heavy mineral placers have been identified from Siri River in CGGC. Pegmatites analysing encouraging Li values in parts of Korba district, Chhattisgarh and Jharsuguda district, Odisha have been mapped recently (See under RMRE).
Sub-surface exploration efforts have been intensified for migmatite-hosted granite related and shear-controlled metamorphitetype uranium mineralisation in CGGC; a number of radioactive anomalies hosted in pegmatiticleucosome of migmatiteidentified at North Surguja, Central Surguja and Tan Shear Zones.
Middle Proterozoic Chhattisgarh &Khairagarh basins (Dongargarh- Kotri belt) and Pakhal basin having unconformable contact with the Lower Proterozoic / Archaean basement have been taken up for unconformity related uranium occurrences intensive investigations. In recent years, focus is also on locating IOCG or volcanic type uranium mineralisation in Proterozoic acid volcanics, and metamorphite type uranium mineralisation in Proterozoic supracrustals.
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