Abstract Tectonostratigraphic development of the c. 300 km-long Nellore schist belt (NSB) of southern India is described in relation to the post-Neoarchaean growth of the Dharwar cratonic nucleus. Lying along the eastern margin of the Dharwar cratonic nucleus, the NSB comprises several geologically and geochemically distinct tracts of deformed Palaeoproterozoic to Mesoproterozoic volcanosedimentary successions: the Vinjamuru Group, the Kandra ophiolite complex (KOC), the Kanigiri ophiolitic melange (KOM) and the Udaigiri Group, arranged in relative order of younging. The high-grade Eastern Ghats belt occurs further to the east of the NSB with a tectonic contact. Thrust-transported oceanic crust remnants occur in the 1.9 Ga KOC, 1.34 Ga KOM, and the Vinjamuru Group, which show multiple deformation, amphibolite facies metamorphism and granitic intrusions. The available geological, geochemical and geochronological data have been examined to tentatively constrain the relative age of the different tectonostratigraphic units of the NSB, tectonic juxtaposition and implications in relation to global events in the Proterozoic. Subduction-related ocean closures outboard and east of the Dharwar Craton, evidenced by the KOC and KOM, possibly had links with the assembly of Columbia and its final dispersal, respectively.

Abstract A relatively rapid change in the Earth's surface processes has been anticipated across the Archaean–Palaeoproterozoic boundary as a consequence of changes in the crust–mantle system and tectonic regime ( Condie 1989 , 1997 ; Eriksson et al. 2004 ; Reddy & Evans 2009 ). The Palaeoproterozoic era (2500–1600 Ma: Plumb 1991 ) represented perhaps the first supercontinent cycle, from the amalgamation and dispersal of a Neoarchaean supercontinent to the formation of the 1.9–1.8 Ga supercontinent Nuna ( Reddy & Evans 2009 ), and encompasses one or more global tectonic event that coincides with fundamental changes in the integrated system of core, mantle, lithosphere, hydrosphere, atmosphere and biosphere (i.e. an integrated Earth System). An integration of seemingly disparate geoscience disciplines is therefore an essential prerequisite to understand these changes ( Reddy & Evans 2009 ); and that was the aim of the UNESCO-IGCP 509 project (2005–2009) on Palaeoproterozoic Supercontinents and Global Evolution. The fifth and final conference and post-conference field workshop (in the Singhbhum Craton) related to the UNESCO-IGCP 509 project was organized by the Indian Statistical Institute (ISI), Kolkata with financial support from the UNESCO, the ISI, and the Council of Scientific and Industrial Research, Government of India during the period 26 October–3 November 2009. An entire session was devoted to the Palaeoproterozoic geology of India, as the Indian Shield represents a vast repository of the Palaeoproterozoic geological record. While most of the papers presented in this session were essentially on Palaeoproterozoic geology of the Indian Shield

Abstract The Archaean–Proterozoic rock successions in India have the potential to enrich the global database on Precambrian stratigraphic development, and to offer valuable clues to global tectonic reconstructions. Built over four distinct Archaean cratonic nuclei, the major Palaeoproterozoic supracrustal belts/cover sequences include the Dhanjori Group, the Singhbhum Group (including the Dalma volcanics and the Chandil Formation in eastern India), the Cuddapah Supergroup and the adjoining Nellore Schist Belt bordering the eastern Dharwar Craton, the Aravalli Supergroup in the Aravalli–Delhi Fold Belt in NW India, the lower Vindhyan (Semri Group) and the Mahakosal/Sausar/Betul belts close to the Central Indian Tectonic Zone (CITZ), and, possibly, the Dongargarh Supergroup in Bastar. A major erosional unconformity separates the Archaean tonalite–trondjhemite gneiss basement in these cratons from the overlying volcano-sedimentary successions. An overview of Palaeoproterozoic stratigraphic development in these cratonic blocks is presented to bring out the salient features for global comparison and to highlight issues requiring further attention. Multiple metamorphic, magmatic and deformation events are recorded in the fold belts at the join of the cratons or their margins, inviting application of the plate tectonic paradigm. However, a comprehensive tectonic model for the amalgamation of the Indian Archaean nuclei is yet to emerge, and is crucial for our understanding of Palaeoproterozoic supercontinent development.

Abstract The Proterozoic Cuddapah Basin of south India hosts a number of unconformity-bound sequences deposited over continental crust. The Palaeoproterozoic Papaghani Group with basal polymict conglomerate unconformably overlies the Archaean Peninsular Gneiss and set the stage for Palaeoproterozoic sedimentation following a long hiatus. Two cycles of fluvial–shallow-marine psammite–carbonate–pelite sedimentation in the western part of the basin (Papaghni sub-basin) is punctuated at different levels by mafic flows, sills and dykes, and less common acidic tuffs. Each of the sedimentation cycles fosters extensive carbonate platforms with dolomitic stromatolites and algal laminites. Emplacement of shallow crustal intrusives at the end of the first cycle was possibly linked to thermal anomalies in the mantle and associated widespread crustal extension in south India. Brittle fault-slip analysis from the western Cuddapah indicates repetitive extensional to strike-slip regimes. This paper proposes a likely late Palaeoproterozoic shallow-marine sedimentary sequence of the Nallamalai Fold Belt as allochthonous, thrusted over the successions of the Papaghni sub-basin and the Kurnool Group in the western part of the basin. Inversion of the Papaghni sub-basin and the development of regional erosional unconformities is discussed in the context of Palaeoproterozoic and early Mesoproterozoic orogenic events at the SE margin of India.