Is there a need for variable density option in making combined mass correction to gravity data acquired over high relief?

Abstract

Traditional gravity data processing involves terrain and Bouguer corrections with uniform density. However, inclusion of variable densities honouring surface geology in such corrections is a long-felt need. This matter assumes fundamental importance for gravity data acquired over high relief. So, improved Bouguer and terrain correction scheme is proposed and its utility is demonstrated on a gravity profile along Mahe-Sumdo-Tso Morari of Ladakh Himalaya. A maximum difference of about 50-70 mGal in the final Bouguer anomaly is observed between data processed through normal procedure with uniform Bouguer density (= 2.67 g/cm3) and those proposed with variable density. This underlines the importance of the proposed scheme.