Petrogenesis and geochemistry of fayalite and fluorite-bearing granite from the Assam Meghalaya Gneissic Complex, West Khasi Hills, Meghalaya, India: their implication towards Rodinia Supercontinent amalgamation

The present study reports fayalite-bearing granite bodies from the Assam–Meghalaya Gneissic Complex of North East India. These are weakly peraluminous with high amounts of alkalis and meagre contents of magnesium, calcium, titanium and phosphorus. The chondrite normalized REE pattern is flat, having minor enrichment of HREE with negative europium anomaly suggesting their A-type character. The discrimination based on Rb, Y, Yb, Nb and Sc content indicates their generation due to melting of crustal components. Early crystallized fayalite and fluorite grains indicate that their emplacement in an extensional tectonic set-up most possibly represents the final stage of Rodinia Supercontinent amalgamation