气候变化领域集成服务门户(CCPortal): Lower-altitude of the Himalayas before the mid-Pliocene as constrained by hydrological and thermal conditions

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DOI	10.1016/j.epsl.2020.116422
	Lower-altitude of the Himalayas before the mid-Pliocene as constrained by hydrological and thermal conditions
	Chen C.; Bai Y.; Fang X.; Xu Q.; Zhang T.; Deng T.; He J.; Chen Q.
发表日期	2020
ISSN	0012821X
卷号	545
英文摘要	Contradictory paleoaltitudinal histories of the Himalayas arrived at using isotopic paleoaltimeters and ecological evidences have constrained our further exploration of the geodynamic mechanisms driving the India-Eurasia collision and the resultant interaction between tectonic uplift and climate change. In this study, based on evidence derived from glycerol dialkyl glycerol tetraethers (GDGTs), the hydrogen isotopes of leaf wax n-alkanes (δ2Halk), we estimated the paleoaltitude of the Gyirong Basin (GB), central Himalayas, for the 7.0∼3.2 Ma period. The paleoaltitudinal reconstruction based on δ2Halk values (∼6.3 km above sea level (asl)) was consistent with that of the revised δ18Oc values (∼5.6 km asl), and higher than the present-day altitude (∼4 km asl). The reconstructed paleotemperatures based on brGDGTs (14.2 ± 4.5 °C for the lake surface; 7.5 ± 3.3 °C for terrestrial organic matter source areas) were consistent with the ecological evidences, indicating a low-altitude paleoenvironment. This proves that a systemic bias exists between the isotopic paleoaltimeters and the ecological evidence, rather than a problem with specific indicators. The reconstructed paleoaltitudinal differences between the δ2Halk and δ18Oc values are similar to those of brGDGT reconstructions, seemingly representing the paleoaltitudinal differences between the source areas of terrestrial organic matter inputs and the lake surface, and suggesting that the isotopic palaeoaltimeters do not specifically record the higher-altitude parts of the basinal topography. Further paleoenvironmental analysis indicated that the warmer and wetter environment present during the Late Miocene to Mid-Pliocene would, on the face of it, be better suited to the application of brGDGT paleothermometers, and this in turn would potentially lead to a systemic overestimation by isotopic paleoaltimeters. We therefore adopted the paleoaltitudinal reconstructions which used brGDGTs and concluded that the lake surface of the GB during the Late Miocene to Mid-Pliocene was 2.5 ± 0.8 km asl, and that the surrounding mountains exceeded 3.6 km asl in height, implying that the central Himalayas underwent a rapid uplift of ∼1.5 km after the Mid-Pliocene. © 2020 Elsevier B.V.
关键词	GDGTs Gyirong Basin hydrogen isotope of leaf wax n-alkanes Late Miocene to mid-Pliocene paleoelevation paleotemperature
英文关键词	Biogeochemistry; Climate change; Ecology; Geodynamics; Glycerol; Lakes; Paraffins; Sea level; Topography; Hydrogen isotope; Low altitudes; Mid-Pliocene; Paleo-environment; Paleotemperatures; Tectonic uplift; Terrestrial organic matter; Thermal condition; Isotopes; altitude; climate variation; collision zone; Eurasian plate; geodynamics; Indian plate; Miocene; paleoenvironment; paleohydrology; paleotemperature; Pliocene; reconstruction; tectonic evolution; uplift; China; Gyirong Basin; Himalayas; Xizang
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/202533
作者单位	CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, China; Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Division of Key Laboratory of Carbonate Reservoirs, CNPC, Southwest Petroleum University, Chengdu, 610500, China; Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China; CAS Center for Excellence in Life and Paleoenvironment, Beijing, 100044, China
推荐引用方式 GB/T 7714	Chen C.,Bai Y.,Fang X.,et al. Lower-altitude of the Himalayas before the mid-Pliocene as constrained by hydrological and thermal conditions[J],2020,545.
APA	Chen C..,Bai Y..,Fang X..,Xu Q..,Zhang T..,...&Chen Q..(2020).Lower-altitude of the Himalayas before the mid-Pliocene as constrained by hydrological and thermal conditions.Earth and Planetary Science Letters,545.
MLA	Chen C.,et al."Lower-altitude of the Himalayas before the mid-Pliocene as constrained by hydrological and thermal conditions".Earth and Planetary Science Letters 545(2020).