Research Projects

Orogenic gold deposits are the most widespread and productive gold-endowed terrains globally, with temporal peaks recognized at 2.8-2.5 giga annum (Ga), 2.15-1.75% Ga, and ~650 million years ago. These deposits exhibit general characteristics such as metamorphosed fore-arc or back-arc, structurally controlled mineralization, post-peak metamorphic timing of mineralization, epigenetic introduction of S, CO2, H2O, Si, and Au, and H2O–CO2–CH4-bearing mineralizing fluids with salinities at 3-10 wt% NaCl eq. This knowledge has led to the recognition of a universal "metamorphic devolatization model" for the formation of such deposits. However, the source of gold in this model remains equivocal, with potential sources including the subducted oceanic lithosphere, metasomatized lithosphere, and underlying continental crust. Recent research recognizes a dominant carbonaceous sedimentary source of gold for most Phanerozoic gold deposits, but the source of gold in Precambrian deposits remains debated. The Proterozoic deposits are further intensified due to their relative rarity globally and mineralization typically hosted in the contact between metavolcanic and metasedimentary rocks. Our understanding of gold reservoirs active during the Proterozoic remains fragmental, impeded by incomplete knowledge. To study the Lawa gold deposit in the Paleo-to Mesoproterozoic Chandil Formation within the North Singhbhum Mobile Belt in eastern India, the author proposes delineating the possible gold reservoir and determining the physico-chemical conditions of the mineralizing fluids.