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

Autor: Ravindran, Arathy, Mezger, Klaus, Balakrishnan, S., Berndt, Jasper, Ranjan, Sameer, Upadhyay, Dewashish
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Chemical Geology, 615
Ravindran, Arathy; Mezger, Klaus; Balakrishnan, S.; Berndt, Jasper; Ranjan, Sameer; Upadhyay, Dewashish (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, p. 121196. Elsevier 10.1016/j.chemgeo.2022.121196
ISSN: 0009-2541
1872-6836
DOI: 10.3929/ethz-b-000583238
Popis: The combination of U–Pb zircon ages with Hf-Sr-Pb isotopes of different intrusive and extrusive felsic and sedimentary rocks provides constraints on the petrogenetic evolution of the continental crust in the western Dharwar Craton, India. The oldest detrital zircon preserved formed at ∼3.6 Ga and represents a relic of the oldest felsic crustal material in the region. The dominant granitoid units of the western Dharwar Craton contain zircon grains with magmatic ages between 3.4 Ga and 3.0 Ga that indicate the formation of major felsic continental crust during this interval. Trace element abundances of the granitoids indicate that the oldest members of the intermediate to felsic suite derived by partial melting of mafic material at ∼3.6–3.4 Ga. The initial bulk rock Hf isotope compositions of these granitoids are consistent with their formation by melting of even older mafic material that was slightly enriched relative to the depleted mantle composition. This mafic and slightly enriched material formed by mantle melting at ∼ < 3.8 Ga. The Hf isotope compositions of individual zircon grains, obtained by two different analytical techniques (in-situ and complete dissolution followed by chromatographic separation) give evidence for the presence of such older mafic material (
Chemical Geology, 615
ISSN:0009-2541
ISSN:1872-6836
Databáze: OpenAIRE
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