Delhi Volcanics in Parts of Central Rajasthan and their Significance

The Proterozoic Delhi Supergroup of rocks along the Aravalli orographic axis in central Rajasthan encloses thick linear piles of syn-sedimentary volcanics. The volcanies are low-potassic oceanic tholeiites derived from mantle source. The repository basin was ensialic to start with and was partially rifted to facilitate magma upwelling concomitant with sedimentation. Structural stratigraphic and chemical characters of the volcanics militate against the possibility of its being allochthonous slices of an oceanic crust.