TY - JOUR
T1 - Relict subduction initiation along a passive margin in the northwest Indian Ocean
AU - Pandey, Dhananjai K.
AU - Pandey, Anju
AU - Whattam, Scott A.
N1 - Funding Information:
This research used samples provided by the IODP Expedition 355. Extended support from the Co-Chief (Peter D. Clift), Program Scientist (Denise K. Kulhanek) and other shipboard members from the scientific and technical team onboard JOIDES Resolution during the course of IODP-355 drilling is gratefully acknowledged. This research is funded by IODP-India at ESSO-National Centre for Polar and Ocean Research, Goa (Ministry of Earth Sciences, India) through Grant no: MoES/PO(Seismo)/3(45)2012. D.P. and A.P. thank Secretary, MoES, Director, NCPOR and Geoscience Division of NCPOR for their support. S.A.W. wishes to thank R.J. Stern, J.W. Shervais, M.K. Reagan and T.V. Gerya for discussions on how subduction initiates. This is NCPOR contribution number: J-02/2019-20.
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - The tectonic evolution of Laxmi basin, presently located along western Indian passive margin, remains debated. Prevailing geodynamic models of Laxmi basin include two mutually competing hypotheses, culminating in either a hyper-stretched continental crust or an oceanic crust overlying an extinct spreading centre. The longstanding conundrum surrounding its precise crustal affinity precludes a complete understanding of the early opening of the Indian Ocean. Here, we present distinct geochemical and geophysical imprints from the igneous crust in Laxmi basin obtained through International Ocean Discovery Program Expedition 355. The geochemical and isotopic signatures of the Laxmi basin crust exhibit uncanny similarities with forearc tectonic settings. Our observations imply a relict subduction initiation event occurred in the Laxmi basin in the Late Cretaceous-Early Cenozoic that marks a significant Cenozoic plate reorganisation record in the northwest Indian Ocean. New findings therefore warrant re-evaluation of the Gondwana breakup to account for the nascent subduction in the northwest Indian Ocean.
AB - The tectonic evolution of Laxmi basin, presently located along western Indian passive margin, remains debated. Prevailing geodynamic models of Laxmi basin include two mutually competing hypotheses, culminating in either a hyper-stretched continental crust or an oceanic crust overlying an extinct spreading centre. The longstanding conundrum surrounding its precise crustal affinity precludes a complete understanding of the early opening of the Indian Ocean. Here, we present distinct geochemical and geophysical imprints from the igneous crust in Laxmi basin obtained through International Ocean Discovery Program Expedition 355. The geochemical and isotopic signatures of the Laxmi basin crust exhibit uncanny similarities with forearc tectonic settings. Our observations imply a relict subduction initiation event occurred in the Laxmi basin in the Late Cretaceous-Early Cenozoic that marks a significant Cenozoic plate reorganisation record in the northwest Indian Ocean. New findings therefore warrant re-evaluation of the Gondwana breakup to account for the nascent subduction in the northwest Indian Ocean.
UR - http://www.scopus.com/inward/record.url?scp=85065977714&partnerID=8YFLogxK
U2 - 10.1038/s41467-019-10227-8
DO - 10.1038/s41467-019-10227-8
M3 - Article
C2 - 31113947
AN - SCOPUS:85065977714
SN - 2041-1723
VL - 10
JO - Nature communications
JF - Nature communications
IS - 1
M1 - 2248
ER -