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Peninsular India is a collage of Archaean cratonic domains separated by Proterozoic mobile belts. A number of cratonic basins, known as “Purana basins” in the Indian literature, formed in different parts of the Indian Peninsula during extensional tectonic events, from Paleoproterozoic through Neoproterozoic times. In this contribution, we present a diversity of new geochronological data for different units within the Kaladgi and the Bhima basins, which overlie the western and eastern Dharwar cratons, respectively. The new geochronology data are discussed in terms of depositional history and provenance of these poorly understood Proterozoic intracratonic basins. For the Kaladgi Group, a U–Pb baddeleyite age of 1,861 ± 4 Ma obtained for a dolerite dyke intruding the Yendigere Formation is used to constrain the minimum age of deposition of the lower Kaladgi Group. This result demonstrates that this part of the succession is comparable in age to the Papaghni Group of the Cuddapah Basin, heralding onset of Purana sedimentation at ~1,900 Ma. The detrital zircon populations from the clastic rocks of the Kaladgi and Bhima basins show unique and distinct age patterns indicating different source of sediments for these two basins. Palaeocurrent analysis indicates a change in provenance from south or southeast to west or northwest between the Kaladgi and Bhima clastic sedimentation. New U–Th–Pb and Rb–Sr radiometric dates of limestones and glauconite‐bearing sandstones of the Bhima Group (Bhima Basin) and the Badami Group (Kaladgi Basin) indicate deposition at around 800–900 Ma, suggesting contemporaneity for the two successions. Thus, the unconformity between the Kaladgi Group and the overlying Badami Group represents a time gap of up to 1,000 Myr. These new results demonstrate the complex multistage burial and unroofing history of the Archaean Dharwar Craton throughout the Proterozoic, with important implications for exploration of metal deposits and diamonds in Peninsular India.

The Cuddapah Supergroup succession can be divided into four unconformity-bound sequences, namely, the Papaghni, Chitravati, Srisailam and Kurnool groups and formation representing four major cycles of sedimentation. The oldest sequence, the Papaghni Group is represented by fan-delta, prodelta and shallow shelf deposits. The rifting stage of the basin evolution is attested by the immature delta succession deposited as a major fault-controlled basin evolution, and was followed by the early subsidence stage. Basement uplift and a hiatus in deposition follows the first cycle of sedimentation. The Chitravati Group, representing the second cycle of sedimentation, consists of mature sandstones separated by a heterogeneous shale-sandstone-dolomite interval. The third cycle starts with the deposition of widespread coastal fluvial to shallow marine sandstone of the Srisailam Formation, and the fourth cycle is represented by the Kurnool Group consisting of conglomerates, feldspathic sandstones, supermature quartzarenites, minor shale and carbonates. Each cycle represents a rifting phase followed by a stable subsidence stage when the basin evolved into a large epicontinental sea. The supermature Gandikota Quartzite of the Chitravati Group and the Paniam Quartzite of the Kurnool Group represent relative sea-level fall and forced regression. The siliciclastics in each of the sequences display signatures of macrotidal sedimentation pointing to open ocean connection. The sequences further display signatures of passive margin sedimentation with multiple events of carbonate-shale rhythmite deposition. Mafic flows and dykes in the Papaghni and Chitravati groups reflect thermal anomalies associated with phased crustal extension; successive extensional phases were punctuated by basin inversion. Extensive and pulsed development of epicontinental seas as recorded in the Cuddapah sequences in the south Indian craton, possibly reflect global sea-level changes associated with supercontinent (eg. Columbia in the Palaeoproterozoic) break-up and assembly.