Density Studies in the Dharwar Craton along the Jadcharla-Goa Subtransect

The Dharwar craton constitutes part of one of the most significant Precambrian shields in the world. Different episodes of deformation undergone by the craton make it difficult to decipher its complex geology. Density studies were conducted along the Jadcharla-Goa subtransect (820 samples), which cuts across the northern part of the craton to understand the geological nature of the region as well as provide a sound base for gravity surveys. Modal densities of 2.65 gm/cc, 2.92 gm/cc and 2.57 gm/cc were obtained for the three major constituents in the region - peninsular gneisses, schists and Closepet granites, respectively. Application of the Kolmogorov-Smimov statistical test on samples from the western and eastern Dharwars along the transect as a whole, as well as from Gadag (western Dharwars) and Makthal (eastern Dharwars) areas indicated that they differed in density values, suggesting they belonged to different population distributions. This, in the light of recent contrary studies, lends support to the concept of division of the Dharwar craton into two groups.