气候变化领域集成服务门户(CCPortal): Sediment provenance of pre- and post-collisional Cretaceous–Paleogene strata from the frontal Himalaya of northwest India

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DOI	10.1016/j.epsl.2020.116079
	Sediment provenance of pre- and post-collisional Cretaceous–Paleogene strata from the frontal Himalaya of northwest India
	Colleps C.L.; McKenzie N.R.; Horton B.K.; Webb A.A.G.; Ng Y.W.; Singh B.P.
发表日期	2020
ISSN	0012821X
卷号	534
英文摘要	Whereas the timing for India–Asia collision remains debated, contrasting collisional models provide testable predictions in terms of sediment source contributions during the accumulation of Paleocene to middle Eocene deposits now exposed in the frontal Himalayan system. Within the Lesser Himalaya and frontal thrust system of northwest India, discontinuous exposures of the Cretaceous Singtali Formation and upper Paleocene–middle Eocene Subathu Formation yield a record of these early collisional stages. To test competing collisional models, we analyze the provenance of these deposits with new detrital zircon U-Pb and Hf isotopic data which can distinguish among Indian plate, Asian plate, Kohistan-Ladahk arc, and various Himalayan sources. Detrital zircon age distributions for the Singtali Formation are dominated by Paleoproterozoic zircons with a distinct Cretaceous age component, whereas age data from the Subathu Formation record (1) a marked increase in the relative abundance of Cambrian–Neoproterozoic grains, (2) a decrease in the proportion of Paleoproterozoic grains, and (3) distinct Permian and Late Cretaceous–Paleocene age components. All Cretaceous grains from the Singtali Formation yielded crustal Hf isotopic signatures, indicating a distinctive pre-collisional source of Cretaceous grains of Indian affinity. Zircon Hf isotopic signatures from <320 Ma grains in the Subathu Formation show a significant lower to middle Eocene increase in source diversity, including juvenile grains most likely originating from the Asian plate and Kohistan-Ladakh arc. This requires inception of India-Asia collision by ∼44–50 Ma—the depositional age of the uppermost Subathu Formation. This major provenance shift is similar to that observed for pre- and post-collisional Tethyan Himalayan strata in the north, which is suggestive of a single contiguous basin linking the Lesser Himalaya by ∼44–50 Ma and contests the notion that the Lesser and Tethyan Himalaya were separated by a “Greater India Basin” during the Eocene. When coupled with the well documented Paleocene–early Eocene provenance record of the Tethyan Himalaya, these new data provide support for a collisional model in which Asian detritus reached the northernmost edge of India by ∼59 Ma with terminal closure of both the Shyok and Indus-Yarlung suture zones by ∼54 Ma. © 2020 Elsevier B.V.
关键词	geochronology Himalaya India–Asia collision northwest India provenance zircon
英文关键词	Binary alloys; Deposits; Geochronology; Hafnium; Isotopes; Lead alloys; Silicate minerals; Uranium alloys; Zircon; Himalayas; Isotopic signatures; northwest India; Paleoproterozoic; provenance; Relative abundance; Sediment provenance; Sediment sources; Zircon deposits; age determination; continental collision; Cretaceous-Paleogene boundary; geochronology; Indian plate; provenance; zircon; Himalayas; India; Lesser Himalayas
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202548
作者单位	Department of Earth Sciences, University of Hong Kong, Pokfulam, Hong Kong; Department of Geological Sciences, Jackson School of Geosciences, University of Texas at AustinTX 78712, United States; Institute for Geophysics and Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, United States; Department of Geology, Panjab University, Chandigarh, 160014, India
推荐引用方式 GB/T 7714	Colleps C.L.,McKenzie N.R.,Horton B.K.,等. Sediment provenance of pre- and post-collisional Cretaceous–Paleogene strata from the frontal Himalaya of northwest India[J],2020,534.
APA	Colleps C.L.,McKenzie N.R.,Horton B.K.,Webb A.A.G.,Ng Y.W.,&Singh B.P..(2020).Sediment provenance of pre- and post-collisional Cretaceous–Paleogene strata from the frontal Himalaya of northwest India.Earth and Planetary Science Letters,534.
MLA	Colleps C.L.,et al."Sediment provenance of pre- and post-collisional Cretaceous–Paleogene strata from the frontal Himalaya of northwest India".Earth and Planetary Science Letters 534(2020).