Geochemical characteristics of amgaon mafic rocks, western bastar craton, central india: emphasis on their palaeotectonic evolution.

The Amgaon mafic rocks occur as restite blocks within Amgaon gneissic complex which are metamorphosed upto amphibolite facies. Low Na2O+K2O (<4%), moderate concentration of SiO2, low differentiation index (DI<30) and solidification index (SI; avg. 32.18) are the characteristics of basic nature of these rocks. Na2O, MgO and CaO/Al2O3 values are similar to MORB (2.68%, 7.6% and 0.74% respectively) values. They show low-K tholeiitic characteristics...