Geological Milieu of the Bijawar Basin based on interpretation of geophysical data; Central India

Abstract

Integrated interpretation through physical properties of rocks provides better approach towards understanding of geological set-up. High resolution heliborne time domain electromagnetic, magnetic and radiometric dataset acquired over Palaeo Proterozoic Bijawar Basin has been interpreted to enhance the geological understanding. The process involved knowledge driven analysis through correlation with geological units that outcrop and data driven analysis for extrapolation of information. Radiometric data in conjunction with spectral remote sensing data was used for generation of surface geology map. Spatial distribution of rock magnetization properties defines the subsurface extension of litho-structural elements and magnetic basement configuration. Electromagnetic data aided demarcation of resistive basement topography and various conductive layers. Radio-elemental distribution refines the unconformable contact shared by Bijawar Group with overlying and underlying group of rocks and also outlined the formational boundaries of arenaceous-argillaceous carbonate-volcano-sedimentary sequence. Subsurface extent of basic volcanics is much more than its surface manifestation and appears to extend well below the overlying Vindhyan Supergroup of rocks. The unconformable contact of Bijawar Group with underlying basement and overlying Vindhyan Supergroup is marked by distinct change in conductivity parameter and has been outlined in depth to resistive basement topography. Fault system and its manifestation over different litho-units indicate multiple tectonic episodes.