Abstract

The Khardeola Formation (~200m) crops out in the Southeastern parts of Rajasthan, as linear patches in the North-South continuation. The Petrographic data reveal that the Khardeola Sandstone comprises of quartz 72%, as dominant framework mineral, with subordinate amounts of feldspar 12% and rock fragments 6% with some opaque and heavy minerals. The Presence of medium to fine, moderately to poorly sorted and subrounded to subangular detrital mineral suggests that the sediments have not been subjected to prolonged transport and reworking, resulting in only a moderate level of maturity. Diagenetic features observed suggest early cementation, porosity reduction during early compaction by the rotation and readjustment of the detrital grains and formation of linear contacts during mechanical compaction as well as dissolution and replacement of feldspar and lithic fragments at later stage. The petrofacies in Qt-F-L and Qm-F-Lt ternary diagrams suggest that these sandstones mainly belong to the continental block, recycled orogen and rifted continental margin tectonic setting. Thus, the study indicates that detrital mineral compositions are not much affected by the paleoclimate, transportation distance. Source rock composition had dominant control. The Khardeola Formation sediments were chiefly derived from Banded Gneisses Complex (BGC) and metasediments of present day Aravalli Super Group.

Keywords: Petrography; Petrofacies; Provenance; Khardeola formation; Vindhyan basin; Rajasthan