Geochemistry and geodynamic setting of Paleoproterozoic granites of Lesser Garhwal Himalaya, India

Abstract

The granite and gneisses rocks are well exposed around Toneta, Tilwara and Chirbatiyakhal region in the Lesser Garhwal Himalaya have less studied which consider as Paleoproterozoic age. The granites from Toneta area are classified as K-rich peraluminous granite with low Na2O varies from 0.85 to 2.4 wt.% and high K2O content varies from 5.0 to 6.9 wt.%. The average Al2O3 (14.16 wt.%) in the granite is greater than the total alkalies (Na2O+K2O = Av. 7.62 wt.%), the Titania (TiO2) content is low ranging from 0.1 to 0.28 wt. %. In the Y + Nb – Rb, Y – Nb, Ta + Yb – Rb, and Yb – Ta discrimination diagram of Pearce et al. (1984) show that the Toneta granites mostly plots within the syn-collision granite fields. This is typical collisional granite.