Bhima Gr
Type Locality and Naming
The NE-SW trending Bhima basin is the smallest among all the Proterozoic basins of India, whose outcropping extent is only about 5200 km2.
Lithology and Thickness
Sandstone, Limestone, Shale in alternating clastic-carbonate cycles. Total of 273 m. Two upward successions: A lower set of Rabanpalli Fm conglomerate-sand, Shahabad Limestone Fm; / Disconformity / upper set of Halkal Fm shale, Katamdevarahalli Limestone Fm, Harwal Fm shale.
[Figure Bhima Gr gield photographs illustrating lithology and sedimentary structures. Rabanpalli Fm - (A) Granule conglomerate and coarse grained sandstone alternation; and (B) Thick-bedded, planar cross-stratified beds alternating with planar parallel beds. (C) Shahabad Limestone Fm - limestone-marl rhythmite. (D) Gray flaggy limestone (Katamdevarahalli Limestone Fm), over brown shale of Halkal Fm. Note sharp contact (black arrow) between the two. (from Saha et al., 2016)]
Relationships and Distribution
Lower contact
Angular unconformity onto greenstone belt, Closepet granite (Archean)
Upper contact
Unconformity to Deccan Traps Fm (end-Cretaceous)
Regional extent
GeoJSON
Fossils
Age
Depositional setting
Base is fan delta; then marine clastics and carbonate platform. On the basis of field evidences the succession may be classified into two major facies associations, representing a shallow water mixed carbonate-siliciclastic stage, and a major transgressive stage depositing sand-free black limestone (Katamdevarahalli Limestone Fm) followed by deposition of second cycle shale (Harwal Fm).
Additional Information