Geochemical constraints on the provenance and tectonic setting of metasedimentary rocks from the South Delhi Supergroup, NW India: implications for tectonic evolution of western margin of the Aravalli orogen

The provenance and tectonic setting of the Stenian (<1200 to 1015 Ma) metasedimentary sequences of the South Delhi Supergroup, NW India, are least understood and thus debatable. The results of this study show that the protoliths of the metasedimentary rocks received detritus dominantly from felsic sources, particularly from Mesoproterozoic granitoids exposed in northern and eastern India. The weathering indices suggest low to moderate weathering in the source areas and that the sediment compositions reflect mixing of provenance components having different compositions. Overall, the REE patterns of the South Delhi rocks are similar with variable negative Eu anomalies and absolute n-ary sumation REE contents. The low REE abundances in the quartzites are the consequence of quartz dilution during hydraulic sorting. The tectonic multidimensional discrimination diagrams suggest a passive margin setting for the South Delhi metasedimentary rocks, which is in consonance with the detrital zircon age spectra and regional geology of the western margin of Aravalli orogen, NW India.

Automated summary

The provenance and tectonic setting of the Stenian metasedimentary sequences of the South Delhi Supergroup in NW India are still unclear and subject to debate. This study found that the metasedimentary rocks mainly originated from felsic sources, particularly Mesoproterozoic granitoids in northern and eastern India. The weathering indices indicate low to moderate weathering, and the sediment compositions reflect a mixture of different provenance components. The tectonic discrimination diagrams suggest a passive margin setting for the South Delhi metasedimentary rocks, consistent with the detrital zircon age spectra and regional geology of the western margin of the Aravalli orogen.