Petrology and Geochemistry of Lamprophyres from Tirthal Area, in Eastern Margin of the Eastern Dharwar Craton, Khammam, Telangana, India

Authors: Debapriya Adhikary, Chinchu S.V.

DOI: https://doi.org/10.37082/IJIRMPS.v12.i2.230594

Short DOI: https://doi.org/gtsghz

Country: India

Full-text Research PDF File:   View   |   Download

Abstract: The presence of lamprophyre dykes is very common in the Eastern Dharwar Craton (EDC), southern India. The present paper reports five new lamprophyre bodies from the Tirthal area near the bank of the Muneru River (80°08ʹ 13.00ʹʹ:17°19ʹ 9.0ʹʹ), north of Khammam, Telangana.Petrography and geochemistry of the lamprophyre dykes are also discussed in this paper. The study area mainly consists of granitoids of Peninsular Gneissic Complex-II (PGC-II) of the EDC. The lamprophyre intrudes the granitoids of the EDC.Petrographic studies revealed the presence of panidiomorphic texture. Euhedral crystals of clinopyroxene, biotite and amphibole are present as phenocryst in the lamprophyre,while k-feldspar, plagioclase feldspar, biotite and apatite are present in the groundmass.The lamprophyre is characterized by SiO2 (40.03%-45.23%), Fe2O3(9.09%-13.45%), MgO (9.78%-11.96%), CaO (8.25%-14.78%), K2O (0.69%-2.37%), TiO2 (1.3%-1.53%) and Al2O3 (9.76%-12.02%) contents. Similarly trace elements analysis gavehigher amounts of Ba (2030-10498ppm), Sr (438-925 ppm), Ni (156-225 ppm), Zr (417-590 ppm), V (141-169 ppm) and Cr(388-482 ppm). All the samples gave higher LREE values as compared to HREE with a total REE content within the range of 1108.50-2004.49 ppm. The lamprophyre is classified as minette belonging to Calc Alkaline Group based on geochemical and petrological studies.

Keywords: Titthal Lamprophyre, Eastern Dharwar Craton (EDC), Calc-Alkaline Lamprophyre (CAL)

Paper Id: 230594

Published On: 2024-04-25

Published In: Volume 12, Issue 2, March-April 2024

Share this