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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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