GEODYNAMIC IMPLICATIONS OF CHROME-POOR ENSTATITITE BODIES IN THE SUKINDA-BOULA-NAUSAHI ULTRAMAFIC SUITES OF ORISSA

Within the Brahmani valley granulite terrane (Eastern Ghats) of Dhenka nal district, Orissa the sporadically outcropping pods of chromite-ric h serpentinite are devoid of chrome-poor enstatitite which occurs abun dantly in the northern Gorumahisani greenstone terrane as well defined units within the chromite-rich suites at Katpal, Sukinda and Boula-Na usahi, Cuttack and Keonjhar districts. Available field evidence is com patible with a model of emplacement of these ultramafic bodies along t he contact between the two terranes in a number of stages involving so ft and hard collision, subduction of Gorumahisani Group oceanic lithos phere below the Eastern Ghats granulites followed by delamination and asthenospheric upwelling. Falsifiability tests for the model have been indicated.