A Field Based Perspective of the Volcanism in Tadpatri Formation of Proterozoic Cuddapah Basin, India: An Analog of the Deccan Traps?

Abstract

Field studies around Pulivendla (14°33′36″N: 78°19′48″E) belonging to the Tadpatri Formation of Proterozoic Cuddapah Basin document three distinct lava flows (based on internal layering), associated sediments (shale and sandstone) and intrusive dyke-sill system. The presence of previously undocumented internal layering namely Lower Vesicular Zone (LVZ), Lower Colonnade Zone (LCZ), Entablature Zone (EZ), Upper Colonnade Zone (UCZ) and Upper Vesicular Zone (UVZ) helps to delineate three lava flows in the study area. The associated sedimentary beds either correspond to lava cessation-period or dynamic lava-sediment interaction due to lava-cascading. The present study in Tadpatri Formation reveals volcano-sedimentological features analogous to that of Deccan Traps. It is postulated that magmatism within Tadpatri Formation might have been largely controlled by Proterozoic syn-rift plume activity (needs further corroboration by high precision major/trace/isotopic analyses).