Some Aspects of Petrology of the Granites of the Western Himalaya

Several granite plutons occur in the Great and Lesser Himalaya in Ladakh, Jammu and Kashmir. These granites assume batholithic to sub-batholithic dimensions and are composed of quartz, orthoclase, microcline, plagioclase, muscovite, biotite, hornblende and tourmaline besides epidote, apatite, futile, zircon, magnetite, ilmenite and sphene as accessories. These granites are peraluminous as the molar proportions of Al₂O₃ is greater than the molar proportions of (K₂O+Na₂O+CaO). High molar AI₂O₃/ (K₂O+Na₂O+CaO) ratios and normative corundum are indicative of the generation of these granites due to partial fusion of crustal materials.