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

ABSTRACT

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 ∑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.

KEYWORDS:

• South Delhi Supergroup
• metasedimentary rocks
• provenance
• tectonic setting
• NW India

Highlights

• The South Delhi metasedimentary rocks received a major contribution from felsic sources, particularly the Mesoproterozoic granitoids.

• The chemical composition of the quartzites was modified as a consequence of quartz dilution during hydraulic sorting.

• The rocks experienced low to moderate weathering, reflecting mixing of provenance components with different compositions and/or weathering histories.

• A passive margin setting for the deposition of the South Delhi metasedimentary rocks has been suggested.

Acknowledgments

We thank three anonymous reviewers, and the Editor-in-Chief, Robert J. Stern for their critical comments, which considerably improved an earlier version of the manuscript. The financial support received from the Ministry of Earth Sciences, New Delhi (MoES/P.O/(Geo)/100(2)/2017) to carry out this work is gratefully acknowledged. We thank Rajiv Kumar for carefully preparing the thin sections.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/00206814.2023.2233024

Additional information

Funding

The financial support for this study was received from the Ministry of Earth Sciences, New Delhi (MoES/P.O/(Geo)/100(2)/2017).