Abstract:
Combination of short-lived 142Nd and long-lived 143Nd isotope anomalies in Archean rocks from the western Dharwar Craton gives an indication for the preservation of heterogeneous mantle domains that developed in the Hadean. The existence of multiple Hadean mantle domains demonstrated by this study also suggests that some of these domains were isolated at different times. The coeval felsic, mafic-ultramafic igneous rock assemblages emplaced in the western Dharwar Craton, India, preserve evidence in their 146,147Sm-142,143Nd isotopes systematics for episodic and spatially limited mantle differentiation events during the Hadean. The petrogenesis of these rock suites involved derivation of now crustal material from these distinct mantle sources that were finally emplaced in the Mesoarchean.
Related
Publication(s):
Arathy Ravindran, Klaus Mezger, S. Balakrishnan, Jasper Berndt, Sameer Ranjan, Dewashish Upadhyay (2023), Formation of Paleo- to Meso-Archean continental crust in the western Dharwar Craton, India: Constraints from U-Pb zircon ages and Hf-Pb-Sr isotopes of granitoids and sedimentary rocks, Chemical Geology 615: 121196.
Arathy Ravindran, Klaus Mezger, S. Balakrishnan, Jasper Berndt (2021), Hf-Nd isotopes from ultramafic and mafic rocks in the western Dharwar Craton, India, record early Archean mantle heterogeneity, Lithos 404-405: 106491.
J. M. Maya, Rajneesh Bhutani, S. Balakrishnan, S. Rajee Sandhya (2017), Petrogenesis of 3.15 Ga old Banasandra komatiites from the Dharwar Craton, India: Implications for early mantle heterogeneity, Geoscience Frontiers 8: 467-481.
User Contributed Keyword(s):
Geochemistry, early Earth, Nd isotopes, isotope geochemistry, continental crust