干旱区生态环境知识资源中心(Arid): Expanded lacustrine sedimentation in the Qaidam Basin on the northern Tibetan Plateau: Manifestation of climatic wetting during the Oligocene icehouse

Arid

DOI	10.1016/j.epsl.2021.116935
	Expanded lacustrine sedimentation in the Qaidam Basin on the northern Tibetan Plateau: Manifestation of climatic wetting during the Oligocene icehouse
	Wu, Minghao; Zhuang, GuangSheng; Hou, Mingqiu; Liu, Zhonghui
通讯作者	Zhuang, GS (corresponding author), Louisiana State Univ, Dept Geol & Geophys, Baton Rouge, LA 70810 USA.
来源期刊	EARTH AND PLANETARY SCIENCE LETTERS
ISSN	0012-821X
EISSN	1385-013X
出版年	2021
卷号	565
英文摘要	The Qaidam Basin in the core area of arid Inner Asia has been considered undergoing continuous aridification over the Cenozoic. However, the Qaidam Basin is marked with expanded lacustrine sedimentation during the Oligocene, which contrasts with the fluvial or deltaic facies stratigraphically below (Eocene) and above (Miocene-present). The Oligocene lacustrine expansion challenges the idea of persistent aridification. To solve the conundrum, we reconstruct a long-term compound-specific hydrogen isotope (delta H-2) record from sedimentary leaf wax n-alkanes to evaluate the paleoclimatic context before, during, and after the Oligocene lacustrine expansion. The delta H-2 results reveal three shifts at ca. 40 Ma, 34 Ma, and 24 Ma. The leaf wax delta H-2 values range from -176.8 parts per thousand to -166.7 parts per thousand from 51 to 40 Ma, followed by an abrupt increase of 23.9 parts per thousand at 40 Ma. We interpret this rapid increase as enhanced aridification due to the coeval retreat of the Paratethys Sea from the region. At 34 Ma, the delta H-2 plunges across the Eocene-Oligocene transition (EOT). Post-EOT delta H-2 values are the lowest, vary with high amplitude from -187.1 parts per thousand to -153.2 parts per thousand, and are associated with the lacustrine facies expansion, indicating a wetter climate. By compiling the regional isotopic proxy studies, we observe the contrasting patterns in paleohydrology conditions since the EOT: the relaxation of aridity in the westerlies region versus the enhanced aridification in the East Asian summer monsoon region. We interpret that the west-east contrasting patterns represent the different climatic responses to global cooling: wetting in the west as a result of the enhanced moisture transport via westerlies replacing the subtropical high, and drying in the east due to the reduction in moisture content associated with weakening East Asian summer monsoon. Wetting in Inner Asia is synchronous with cooling in the ocean (North Atlantic) and on land (Xining Basin). Since 24 Ma, delta H-2 increases in response to warming during the latest Oligocene to the early Miocene when the subtropical high re-occupied Inner Asia, causing the aridity. This study reveals a dynamic climate in Inner Asia with different mechanisms responding to global change. (C) 2021 Elsevier B.V. All rights reserved.
英文关键词	Inner Asia westerlies East Asian summer monsoon compound specific hydrogen isotope Qaidam Basin
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000649176900011
WOS关键词	ISOTOPIC COMPOSITION ; TECTONIC EVOLUTION ; STABLE-ISOTOPE ; ASIAN MONSOONS ; HISTORY ; UPLIFT ; MAGNETOSTRATIGRAPHY ; ARIDIFICATION ; CONSTRAINTS ; WESTERLIES
WOS类目	Geochemistry & Geophysics
WOS研究方向	Geochemistry & Geophysics
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/368678
作者单位	[Wu, Minghao; Zhuang, GuangSheng; Hou, Mingqiu] Louisiana State Univ, Dept Geol & Geophys, Baton Rouge, LA 70810 USA; [Liu, Zhonghui] Univ Hong Kong, Dept Earth Sci, Hong Kong, Peoples R China
推荐引用方式 GB/T 7714	Wu, Minghao,Zhuang, GuangSheng,Hou, Mingqiu,et al. Expanded lacustrine sedimentation in the Qaidam Basin on the northern Tibetan Plateau: Manifestation of climatic wetting during the Oligocene icehouse[J],2021,565.
APA	Wu, Minghao,Zhuang, GuangSheng,Hou, Mingqiu,&Liu, Zhonghui.(2021).Expanded lacustrine sedimentation in the Qaidam Basin on the northern Tibetan Plateau: Manifestation of climatic wetting during the Oligocene icehouse.EARTH AND PLANETARY SCIENCE LETTERS,565.
MLA	Wu, Minghao,et al."Expanded lacustrine sedimentation in the Qaidam Basin on the northern Tibetan Plateau: Manifestation of climatic wetting during the Oligocene icehouse".EARTH AND PLANETARY SCIENCE LETTERS 565(2021).