Tectonic juxtaposition of plume and subduction derived magmatic sequences in the Bababudan greenstone terrane, western Dharwar Craton, India: Constraining crustal accretion processes in a Neoarchean subduction-collision orogeny

[Display omitted] •Vertical and lateral growth of crust from Bababudan greenstone terrane, Dharwar Craton.•Komatiite-picrite-basanite association attributed to interaction between mantle plume and SCLM.•Shallow subduction, slab melting and mantle wedge hybridization at ocean-continent convergence.•3177 Ma xenocrystic zircon in komatiite reflects lower crustal inheritance.•Plume- and arc-derived sequences juxtaposed by subduction-accretion-collision tectonics. Archean greenstone belts in the Western Dharwar Craton preserve important clues on Early Earth geodynamics. Here we investigate the ultramafic-mafic metavolcanic rock sequences from the Santaveri Formation of Bababudan greenstone terrane to address the tectonic evolution, mantle dynamics and crustal growth processes of western Dharwar Craton. The ultramafic volcanic rocks are geochemically classified as komatiite-picrite-basanites, whereas the mafic volcanic rocks correspond to magnesian andesite -Niobium-enriched basaltic andesite association. The pristine mineralogy for these ultramafic volcanic rocks is overprinted by tremolite-actinolite-biotite assemblage marking greenschist facies of metamorphism. The komatiites include Al-undepleted, Al-depleted and Ti-enriched types and share overlapping geochemical characteristics with the picrites. The basanites are distinguished as alkaline ultramafic rocks with total alkali content >3 wt% and MgO > 18 wt%. The coherent association of komatiite-picrite-basanite suggests pervasive plume-lithosphere interaction and complies with polybaric melting of a chemically heterogeneous mantle plume through a subduction-modified sub-continental lithospheric mantle at a rifted cratonic margin. Our results substantiate the role of an Archean mantle refertilized by subduction-driven recycling of Mesoarchean supracrustals concurrent with the onset of subduction event at ≥3.2 Ga. The mafic rocks were derived through melting of a hot oceanic slab and mantle hybridization. The xenocrystic zircon grains from komatiite suggest lower crustal inheritance and reworking of basement gneisses by ascending ultramafic melts. The 3177 Ma magmatic age obtained from these zircon grains indicate a Mesoarchean magmatic event in the genesis of the basement gneisses. The emplacement of komatiite-picrite-basanite association and magnesian andesite -Niobium-enriched basaltic andesite lithologies envisages a post 3.1 Ga Neoarchean crustal growth over Mesoarchean protocontinent of WDC. This crust