U-Pb and Hf isotope records in detrital and magmatic zircon from eastern and western Dharwar craton, southern India: Evidence for coeval Archaean crustal evolution

U-Pb and Lu-Hf isotopic records in detrital and magmatic zircons from the eastern and the western Dharwar craton (EDC and WDC) suggest presence of >= 3.4 Ga crustal components in both the blocks. Magmatic zircon from the western block has ages ranging between 3.1 and 3.2 Ga, while those from the eastern block show a bi-modal age distribution with records of 3.0-3.2 Ga protolith components as well as 2.7 and 2.5 Ga metamorphic overgrowths. Detrital and magmatic zircons from granitoid conglomerate clasts of the western Dharwar block show initial epsilon Hf values consistent with models for the early Archaean mantle, suggesting their juvenile character. Lower epsilon Hf values in younger as well as detrital zircons from eastern Dharwar block reflect importance of reworking of >= 3.2 Ga crust. The combined U-Pb and Hf isotope study strengthens suggestions for contemporaneous crust formation processes in both the western and eastern parts of the Dharwar craton. (C) 2016 Elsevier B.V. All rights reserved.