Geochemical Perspectives on the Permian Barakar Formation, Gondwana Supergroup, WestBokaro Basin, India

Abstract: Early Permian sedimentation within the Gondwana intracratonic basins provides
important insights into the sedimentation history. Integrated petrographic and geochemical
proxies offer an effective means to reconstruct these processes. This study examines
siliciclastic rocks—sandstone, shale, and sandstone–mudstone heteroliths from the Permian
Barakar Formation of the West Bokaro Basin, eastern India. The rocks were analysed for
their mineralogical and geochemical properties to interpret provenance, paleoclimate, paleo-
tectonic setting, paleoredox conditions, and paleo-depositional environment. XRD, SEM, and
petrographic analyses, accompanied by major and trace element chemistry, supported by REE
patterns normalized to PAAS and UCC, indicate a predominant felsic provenance, which is
potentially considered to be the granite-granodiorite rocks of the Proterozoic Chhotanagpur
Gneissic Complex, Singhbhum cratonic block. Higher CIA values with A–CN–K plots, along
with MFRW weathering trends, suggest intense chemical weathering under a warm, humid
climate. Relative abundance of redox-sensitive trace elements (e.g., V, Ni, Cu, Zn, Ce, etc.)
points to oxic-dysoxic (for sandstone) and dysoxic-anoxic (for shale) conditions, often
supported by presence of localized pyrite framboids and abundant organic matter in shales
and heteroliths. Tectonic discrimination diagrams indicate deposition in a passive margin
riftogenic basin. Binary and ternary plots of common major element oxides suggest a
continental-marine transitional depositional setting, indicating marine incursions within the
continental Gondwanaland. The results and the interpretations provide important clues
regarding the Early Permian post-glacial warm paleoclimatic transition within the broader
Gondwana paleogeographic-paleoclimatic framework.