A Review on Petrology and Geochemistry of the Neoproterozoic Malani Igneous Suite and Related Rocks (Northwestern Peninsular India)

This paper reports new mineral and whole-rock geochemical data on the acid volcano-plutonic rocks of the Tusham Ring Complex (TRC) from the Neoproterozoic Malani Igneous Suite (MIS), northwestern Peninsular India and discusses their magmatic evolution, tectonic implication, and geodynamic history. Geochemically, the investigated rocks have the characteristics of hypersolvus, high-K calc-alkaline to shoshonitic, peraluminous and A-type granitoids and they are enriched in SiO2, (Na2O + K2O), Fe/ Mg, Ga/Al, Th, U, REE (except Eu), LILE + HFSE, halogens (F and Cl) and depleted in CaO, MgO, Sr, Cr, Ni, P, Ti and Eu abundances. They also show high heat production (HHP) affinity and high mineralization potential. The high abundances of fluorine (0.80-7.11 wt %) and chlorine (0.44-1.56 wt %) in biotite and the geochemistry of the studied rock types indicate that the acid volcanics and granite massifs of TRC were derived from a halogen-enriched magmatic source under low degree partial melting of crustal protolith. The field, petrography, mineral chemistry, whole-rock geochemistry of the rocks under study, in combination with their tectonic and petrogenetic signatures have proposed that the rift-related Neoproterozoic magmatism of MIS has close linkage with geodynamic evolution of Nagarparkar, Seychelles and Madagascar A-type granitoids during Rodinia breakup.