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7478492 
Journal Article 
Petrology and geochemistry of granites from Kowdipally area, Medak district, Telangana, Southern India 
Srinivas, M; Ningam, N 
2015 
0 
International Journal of Earth Sciences and Engineering
ISSN: 0974-5904 
8 
4 
1540-1545 
English 
The Kowdipally area in the Medak District of Telangana is dominated by granitic suite of rocks of Peninsular Gneissic Complex (PGE) of Precambrian age that are emplaced in an older Basement Complex comprising of amphibolites and deformed migmatites and gneisses. The investigated area forms a part of Esatern Dharwar Craton and the lithological variants range from tonalite- granodiorite (TTG), through Granite -adamellitegranodiorite (GAG) to syenogranite (MS) to alkali feldspar granite-quartz syenites. The paper attempts to highlight the salient features of petrography, geochemistry and petrogenesis of granite suite of rocks that are noticed as intrusive bodies around Kowdipally area of Medak district in Telengana State. Megascopically, the granites are medium to coarse grained, inequigranular and porphyritic in texture and composed of K-feldspar (42- 53% represented by microcline perthite), plagioclase (14- 20%) and quartz (21- 25%) in the order of decreasing abundance. Mafic minerals include amphibole (4-9%) and biotite (2-8 %) and accessories like magnetite, sphene, calcite and apatite. Presence of discrete plagioclase grains in substantial proportions attributes to subsolvus conditions of crystallisation of parental magma. The rocks are marked by high SiO2 (72.4 – 73.08%), high K2O (6.44-6.54%) and rather low Na2O (3.08- 3.40 %), with a calc-alkaline signature with a low iron enrichment trend attesting to a typical trait acquired by granites that are presumed to have originated from a LILE-enriched lithospheric mantle. The chondrite normalised REE patterns of the granites display LREE-enriched and HREEdepleted patterns and have a high LREE/HREE ratio that hints at the fractional crystallisation process as a major process. Further, the negative Eu anomaly indicates the role of feldspar in their genesis. 
Geochemistry; Granite; K-feldspar; Kowdipally; Medak district; Petrology; Telangana; Feldspar; Lithology; Petrography; Phosphate minerals; Silicates; fractional crystallization; igneous geochemistry; petrogenesis; Precambrian; rare earth element; Dharwar Craton