Delhi-Pre-Delhi Relation at Lalsot, Jaipur District, Rajasthan: A Reappraisal

The Lalsot-Bayana hills in northeastern Rajasthan are dominated by the Delhi Group of rocks which are folded on a regional scale. In Lalsot hill region, extending from Chainpura in the north to Lalsot town in the south, a remarkable feature is the occurrence of unconformity between the Delhi Group and the underlying older rocks (Pre-Delhi).

Structural and lithostratigraphical mapping indicate that at Lalsot, the unconformity is a mistaken identity between two units of the same stratigraphical succession. Both the units belong to the Delhi Group and these have been renamed as 'Lalsot quartzite' and' Lalsot schist'. There is no evidence to suggest that the Lalsot schist was a metamorphosed unit prior to the onset of deformation and metamorphism.