A2-Type Granites from the Bastar Craton, South-Central India, and Their Implication in Archean-Paleoproterozoic Tectonics in Indian Peninsula

Abstract This communication reports novel geochemical and geochronological data of granite from the southeastern part Bastar Craton, Central India. The studied samples are leucocratic in appearance composed quartz, K-feldspar, plagioclase feldspar, biotite decreasing order abundances. Apatite, sphene, zircon occur as accessory minerals. SiO2 Al2O3 content sample varies between 61 69 wt.% 13 15 wt.%, respectively. alkali oxides, K2O, Na2O ranges 3 6 2 wt. %, In primitive mantle normalized spider diagram, granites exhibit a negative Nb–Ti, Sr anomaly, positive Pb–Th anomaly. Similarly, REE plot, strongly fractionated trend La/YbCN=10.90−28.4 with Eu anomaly (0.42-0.70). saturation silicate melt yields crystallization temperature (Tzr) ~650 to 800°C for Eastern Craton rocks. P-T pseudosection modeling implies EBC which crystallized at 700-750°C, 0.4 0.6 GPa. SHRIMP U-Pb ages magmatic yield an upper intercept ~2470 Ma lower ~2100 Ma. When combined results modeling, classifies rocks A2 that were emplaced during amalgamation Archean blocks leading extended Ur formation. age is correlated mafic dyke emplacement Craton–Yilgarn block disintegration before Paleoproterozoic Columbia supercontinent assembly.