Geochemistry of Hindoli Group metasediments SE Ar

Authors: Asha Saxena M K Pandit

Publish Date: 2012/04/20

Volume: 79, Issue: 3, Pages: 267-278

PDF Link

Abstract

The southeastern fringe of the Precambrian Aravalli fold belt has been designated as Jahazpur Belt which includes two greenschist facies metasedimentary lithopackages Hindoli Late Archean/Paleoproterozoic and Jahazpur Paleoproterozoic Groups We present geochemical data on metapelite phyllite and metagreywackes from the Hindoli Group Metapelites are enriched in alumina while metagreywackes show a wide range and higher abundance of silica Covariance between TiO2 — Al2O3 K2O — Al2O3 pairs and moderate to high SiO2/MgO ratios indicate a strong weathering control Chemical Index of Alteration CIA = 68 for metagraywackes 75 for metapelites reveals moderately weathered protoliths for them Fractionated LREE pattern with almost flat HREE trend and moderate to high Eu anomalies Eu/Eu = 066 to 08 indicate feldspar bearing granite — granodiorite as probable compositions in the provenance Very high PIA values 93 for metapelites reflect almost complete feldspar dissolution while the corresponding values for metagraywackes 68 are relatively lower The diagnostic immobile trace elements Sc Zr Th can be interpreted as a variable felsic source mainly granitic and subordinate granodioritic for metagreywackes and a granodioritic more mafic one for metapelites Considering the broad Precambrian geological setup of NW India the Banded Gneiss Complex BGC which predominantly comprises TTG gneisses and granites amphibolite etc seems to be the most likely provenance for Hindoli sediments

Keywords: