Six Decades of Uranium Exploration in the Proterozoic and Phanerozoic Formations of Himalaya: Challenges, Understanding and Strategies

The Himalayan geo-environment with a six-decade long history of Uranium exploration by Atomic Minerals Directorate (AMD) commenced way back in early 1960’s, has helped in identifying scores of uranium shows. Five major types of uranium mineralization viz., (i) Vein, (ii) Shear controlled hydrothermal, (iii) Disseminated, (iv) Syngenetic and (v) Sandstone hosted, have been identified, which for the ease of exploration, are further grouped as per their respective locales in the four Himalayan tectonic blocks. viz., (i) Sub or Outer Himalaya, (ii) The Lesser Himalaya (iii) Upper or Higher Himalaya and (iv) Para or Trans Himalaya. The vast spread of uranium metallogeny in the Himalaya from Precambrian to Tertiary is a very favorable factor for locating significant uranium deposits. Himalayan orogen is highly dynamic with continued tectonic evolution throughout its geological history. This poses several constraints on exploration strategies, both in terms of logistics and diversified geology. However, the tectonic evolution and regional correlation have been understood to a large extent, which have helped in identifying some common controls and potential locales for uranium metallogeny and hence may be taken as a guide for further detailed exploration.