An explanation of the field and petrographic features of granitic rocks in Narsapur area of medak District, Telangana, India

Abstract

The study area, Narsapur Mandal in Medak district, Telangana State, is at a distance of 60 km NW of Hyderabad. The area covers geological out crops in and around Narsapur.To research the petrographic variations in the rocks, a total area of around 44 square kilometres has been covered. This area represents the geology of the investigated area. It is primarily composed of Precambrian granite and its varieties, such as quartz syenite, quartz monzonite and alkali feldspar granite. Alkali feldspar granite dominates the NE, W, SE, S and SE regions of the area, alkali feldspar and quartz syenite dominates the NW and SE regions, quartz monzonite and quartz syenite dominate the middle region. From all of the nearby outcrops, the nine most representatives in-situ, fresh and unweathered samples were gathered. These plutons' variations in structure and mineral makeup are sufficiently diverse that the name “migmatite” must be used and their mutual field interactions always remain mysterious. The structural fabrics also demonstrate the batholiths' complexity. It is included that differences in mechanical dilution of mafic magma, fractional crystallisation, and diffusive fractionation are responsible for the variability in compositional variation of medak granite. The geochemical data support the idea that subduction had a part in the formation of these rocks.