气候变化领域集成服务门户(CCPortal): Distribution of biomarkers in lacustrine sediments of the Linxia Basin, NE Tibetan Plateau, NW China: Significance for climate change

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DOI	10.1016/j.sedgeo.2011.10.006
	Distribution of biomarkers in lacustrine sediments of the Linxia Basin, NE Tibetan Plateau, NW China: Significance for climate change
	Wang, Yongli; Fang, Xiaomin; Zhang, Tongwei; Li, Yuanmao; Wu, Yingqin; He, Daxiang; Gao, Yuan; Meng, Pei; Wang, Youxiao
通讯作者	Fang, XM (通讯作者)
发表日期	2012
ISSN	0037-0738
EISSN	1879-0968
起始页码	108
结束页码	116
卷号	243
英文摘要	In this study, n-alkanes, isoprenoids and n-alkyl-ketones were detected in lacustrine sediments in the Maogou section of the Linxia Basin, NE Tibetan Plateau, NW China. The distribution characteristics of these compounds correspond to arid climate change in inland Asia from the upper Oligocene to the Pliocene. The characteristic bimodal distribution of n-alkanes, which was observed in the investigated samples, is centered on n-C-17-n-C-20 and has maximum values at n-C-18 in all samples; n-C-27-n-C-31 has maximum values at n-C-29 in some of the samples. The front mode shows a weak even carbon number predominance of short-chain n-alkanes (CPI17-21 0.55-0.89); in contrast, the back mode has a strong odd carbon number predominance of long-chain n-alkanes (CPI25-31, 1.41-2.42). Changes in the nC(27)/nC(31) ratio (woody plants/grassy plants) along the entire section corresponded to three climate stages: an arid to humid climate stage from similar to 22.5 to 18.4 Ma; 6.25 to 5.5 Ma; and two major humid stages at similar to 18.4 Ma and similar to 5.5 Ma. A warm-humid climate was identified for the similar to 10 Ma to similar to 9 Ma period, which turned to an arid-cold climate from similar to 8 Ma to similar to 7.5 Ma, by assessing changes in the (n-C-17-n-C-21)/(n-C-27-n-C-31) ratios. Warm-humid conditions gradually increased from similar to 7.5 Ma to similar to 5.5 Ma, as has been confirmed by multiple geochemical climate indicators. A distinctive climate change toward arid-cold conditions at similar to 8 Ma corresponded to a striking increase in the high-carbon-numbered n-alkanes and a rapid decrease in the (n-C-17-n-C-21)/(n-C-27-n-C-31) and n-C-27/n-C-31 ratios of n-alkanes, which suggests a large input of higher plants. Our observation from the biomarker analysis is in agreement with previous reports that used palynofloras to determine that climate change in the investigated region responded to the uplift of the Tibetan Plateau at similar to 8 Ma. (C) 2011 Elsevier B.V. All rights reserved.
关键词	LONG-CHAIN ALKENONES ORGANIC-MATTER LAKE-SEDIMENTS LOESS-PLATEAU MOLECULAR FOSSILS LATE MIOCENE MODERN SOILS LIPIDS RECORD GEOCHEMISTRY
英文关键词	Biomarkers; Lacustrine sediments; Arid environmental change; Climate significance; NE Tibetan Plateau
语种	英语
WOS研究方向	Geology
WOS类目	Geology
WOS记录号	WOS:000300128900007
来源期刊	SEDIMENTARY GEOLOGY
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258025
推荐引用方式 GB/T 7714	Wang, Yongli,Fang, Xiaomin,Zhang, Tongwei,et al. Distribution of biomarkers in lacustrine sediments of the Linxia Basin, NE Tibetan Plateau, NW China: Significance for climate change[J]. 中国科学院青藏高原研究所,2012,243.
APA	Wang, Yongli.,Fang, Xiaomin.,Zhang, Tongwei.,Li, Yuanmao.,Wu, Yingqin.,...&Wang, Youxiao.(2012).Distribution of biomarkers in lacustrine sediments of the Linxia Basin, NE Tibetan Plateau, NW China: Significance for climate change.SEDIMENTARY GEOLOGY,243.
MLA	Wang, Yongli,et al."Distribution of biomarkers in lacustrine sediments of the Linxia Basin, NE Tibetan Plateau, NW China: Significance for climate change".SEDIMENTARY GEOLOGY 243(2012).