Crustal structure of the northern part of the Proterozoic Cuddapah basin of India from deep seismic soundings and gravity data

A crustal depth section was obtained from Deep Seismic Soundings (DSS) along the Alampur-Koniki-Ganapeshwaram profile, cutting across the northern part of the Proterozoic Cuddapah basin, India, running just south of latitude 16° N and between longitude 78° E and 81°E. The existence of a low-angle thrust fault at the eastern margin of the Cuddapah basin (Kaila et al., 1979) was confirmed along a second profile. Another low-angle thrust, along which charnockites with the granitic basement are upthrust against the Dharwars was delineated further east. The contact of the khondalites (lower Precambrian) with quaternary sediments near the east coast of India seems to be a fault boundary, which may be responsible for the thick sedimentary accumulation in the adjoining offshore region.