Bastar and Singhbhum Cratons With Their Mobile Belts and Gondwana Grabens

Abstract The early Precambrian Bastar and Singhbhum cratons, with their intimately associated Proterozoic mobile belts, are subdivided into disparate terranes by a number of long, deep, and curvilinear shear zones of Precambrian antiquity. Although the orthogonal Gondwanic Godavari Graben defines the western limit of the Bastar, the Mahanadi Graben separates the Bastar from the Singhbhum domain. Despite a multiplicity of terrane-defining curvilinear seismogenic shear zones, no work on neotectonism has been done in this part of the Indian subcontinent. A notable feature is that the laterite-mantled terrain characterized by many planation surfaces and delimited by escarpments has become rugged in some belts. Down these scarp faces descend rivers and streams as waterfalls. All these features collectively indicate the Late Quaternary uplift. In a sector of the E–W-trending, much-faulted Damodar Graben in the Singhbhum domain, palaeochannels are associated with archaeological remnants, implying tectonic disturbance in historical time in the graben zone.