An Integrated Sedimentological and Provenance Study of the Lower Part of the Kurnool Sub-Basin, Cuddapah Supergroup, India: New Evidence for the Neoproterozoic Sedimentary Basin Evolution

We propose a comprehensive picture of the tectono-sedimentary evolution of the lower part of the Neoproterozoic Kurnool Sub-basin, Cuddapah Supergroup, Indian Subcontinent in connection to the Supercontinent Rodinia breakup and assembly (1000–541 Ma) examined from extremely well-preserved sedimentary rocks of the Banaganapalle Sandstone and Narji Limestone. Based on an integrated study of sedimentological and petrographic signatures of the Banaganapalle Formation (BF), we analyzed the processes governing the sand generation, intrabasinal recycling, and temporal changes in sandstone composition. The BF witnesses a fan delta to wave-dominated shoreface to foreshore depositional system with intermittent storm and tidal flat deposits and preserves evidence of eolian and aqueous reworking in the coastal regime. The temporal compositional changes in the BF indicate two different provenances: crystalline Archaean granite–gneissic basement rocks and intrabasinal recycled older sedimentary rocks of the Cuddapah Supergroup and their intermixing. The BF gradually changes to plane parallel laminated heterolithic siltstone–calcareous shale unit to the Narji Limestone characterized by shallow water combined flow generated sub-tidal carbonates followed by parallel laminated deep-water carbonates. The subsequent deposition of the BF and the Narji Limestone represents the initiation of a rifting phase in an intracratonic basin followed by stable carbonate platform sedimentation in an epeiric sea. Overall fining upward section with individual coarsening up package of the BF represents a transgressive system tract (TST) which is followed by a stable carbonate platform, indicating a highstand system tract (HST). The boundary between two system tracts defined by heterolithic unit represents the maximum flooding surface (MFS).