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The Eastern Dharwar Craton (EDC) is predominantly made of Neoarchean potassic granitoids with subordinate linear greenstone belts. Available geochemical and isotopic systematics of these granitoids suggest variations in the source and petrogenetic mechanisms. By compiling the available geochemical data, these granitoids can be classified into four groups, namely: TTGs (tonalite–trondhjemite–granodiorite); sanukitoids; biotite and two-mica granites; and hybrid granites. This classification scheme is in line with the global classification of Neoarchean granites, and enables the sources and petrogenetic mechanisms of these variants to be distinguished. Available geochemical, isotopic and geochronological datasets of these granitoids are integrated and the existing tectonic models for the Neoarchean EDC are reviewed. The variability of the EDC granitoids is ascribed to crustal reworking associated with the collision of two continental blocks. The tectonomagmatic evolution of the EDC is analogous to the development of the Himalayan Orogeny. Based on the evolutionary history of the Dharwar Craton, it can be concluded that convergent margin tectonics were operational in the Indian Shield from at least c. 3.3 Ga and continued into the Phanerozoic. However, the nature and style of plate tectonics could be different with time.

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Archean-Proterozoic boundary represents a significant transitional phase in the Earth's history. Bastar Craton is one of the major Archean cratons in the Indian subcontinent with voluminous granites, supracrustal rocks, and tectonic belts. Malanjkhand, Dongargarh, and Kanker are the three major granitic plutons emplaced during the Archean-Proterozoic transition in the Bastar Craton, and this study is confined to the granites of Kanker pluton. Based on geochemical systematics, the Kanker granites are classified into sanukitoids, biotite and two-mica granites, and hybrid granites. The compositional diversity of the Kanker granites is attributed to two end-member sources, i.e., the enriched mantle and an older felsic crust, and the interactions between them. The sanukitoids were derived from an enriched mantle source that was metasomatized by the subducted sediments. Heat supplied by the sanukitoid magmas induced the crustal melting to form the biotite and two-mica granites. The interaction between these two mutually end-member sources, i.e., the enriched mantle and an older felsic crust, resulted in the formation of hybrid granites. The evolution of the Kanker granites can be accounted for a transitional geodynamic environment, involving subduction, and collisional tectonics during the Archean-Proterozoic transition.

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The interaction between the coeval mafic and felsic magmas result in mixing, mingling, and chemical exchanges between both the end‐member magmas. We document the features relevant to the magma chamber processes and quantify the extent of mixing by means of detailed field, petrographic, mineral, and whole‐rock geochemistry from one of the less known granitic plutons from the Pithora region that forms part of the Kanker granite, Bastar Craton. The study area is composed of granite, granodiorite (mixed zone), and quartz diorite microgranular enclaves (MEs). The occurrence of syn‐plutonic mafic dykes, cuspate contact, magmatic flow textures, and hybridization suggest the coeval emplacement of end‐member magmas. Petrographic evidence such as disequilibrium textures such as resorption, quartz ocelli, and spikes in plagioclase, acicular apatites, and mafic clots are formed by magma mixing. Plagioclase from MEs and the mixed region exhibit disequilibrium textures such as normal, reverse, and oscillatory zoning suggestive of magma mixing. Whole‐rock geochemical data indicates the metaluminous to peraluminous host granites and metaluminous ME. The broadly linear trend of geochemical variation diagrams for these granitoids and MEs showcase the hybridization of two end‐member magmas. The mineral chemistry of the biotites and hornblende show subduction affinity, being further constrained by whole‐rock trace elemental systematics. The granitoids of Pithora region were formed in a subduction setting where large‐scale mantle‐ and crustal‐derived magmas were generated and subsequently mixed at crustal emplacement level.

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