Mesoproterozoic differential metasomatism in subcontinental lithospheric mantle of Central Indian Tectonic zone: Evidence from major and trace element geochemistry of padhar mafic-ultramafic complex

摘要

Metasomatism above subduction zone is an important process capable of producing a heterogeneous mantle wedge with locally varying characters. This, in turn, leads to variation in character of the mafic and intermediate rocks produced through partial melting of lithospheric mantle. The Padhar mafic-ultramafic complex is situated in western part of the Betul belt, Central India, shows enrichment in Rb, Ba, Th and Pb and depletion in Nb, Hf and Zr. Major and trace element data along with REE, confirms the presence of a metasomatized mantle above a Mesoproterozoic subduction zone. Differential petrological evolution, corresponding to the different magma batches, as reflected in almost all of the binary element / oxide variation diagrams, testifies small scale metasomatic heterogeneity in the underlying suprasubduction zone mantle wedge.