气候变化领域集成服务门户(CCPortal): Chlorite weathering linked to magnetic enhancement in Red Clay on the Chinese Loess Plateau

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DOI	10.1016/j.palaeo.2019.109446
	Chlorite weathering linked to magnetic enhancement in Red Clay on the Chinese Loess Plateau
	Ye, Chengcheng; Yang, Yibo; Fang, Xiaomin; Zan, Jinbo; Tan, Mengqi; Yang, Rongsheng
通讯作者	Yang, YB ; Fang, XM (通讯作者)
发表日期	2020
ISSN	0031-0182
EISSN	1872-616X
卷号	538
英文摘要	Magnetic parameters are widely used in the loess-palaeosol sequence tracing Quaternary climate change on the Chinese Loess Plateau (CLP). However, the climatic implication and magnetic enhancement mechanism in aeolian Red Clay on the CLP is still debated. Chlorite is a common Fe-bearing silicate in Red Clay and it is easily to be weathered. The transformation of weakly magnetic ferrihydrite, a product in chlorite weathering process, into strongly magnetic iron oxides has been linked to magnetic enhancement in many soils. Here, we present a complete chlorite weathering record within the Red Clay sequence through a detailed mineralogical investigation, from a 125-m thick eolian Red Clay deposit in the Chaona section (similar to 8.1 to 2.6 Ma) of the central CLP to explore the link between changes in chlorite geochemical composition and magnetic susceptibility enhancement and regional climate. The results suggest a concomitant evolution of chlorite Fe content and magnetic susceptibility, indicating that Fe released from chlorite brucite-like interlayers, which induced ferrihydrite formation, is responsible for the enhanced magnetic susceptibility in the CLP Red Clay deposits. Moreover, the results also show that the chlorite Fe content exhibited a stepwise decrease, with two accelerated stages at similar to 6.2 Ma and similar to 3.6 Ma. The post-6.2 Ma evolution of chlorite Fe content is related to increased precipitation caused by phased enhancement of the East Asian summer monsoon (EASM). Our study also suggests that changes in chlorite chemical composition and crystallinity linked to soil weathering are useful proxies in tracing past weathering intensity and climate change within arid-less humid regime.
关键词	PAST 8 MA ISOTOPIC VARIATIONS EOLIAN DEPOSITS RECORD MONSOON UPLIFT IRON SUSCEPTIBILITY FERRIHYDRITE EVOLUTION
英文关键词	Fe/Mg ratios; Magnetic susceptibility; Ferrihydrite; East Asian summer monsoon; Tibetan Plateau
语种	英语
WOS研究方向	Physical Geography ; Geology ; Paleontology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary ; Paleontology
WOS记录号	WOS:000508751800021
来源期刊	PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
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/259691
推荐引用方式 GB/T 7714	Ye, Chengcheng,Yang, Yibo,Fang, Xiaomin,et al. Chlorite weathering linked to magnetic enhancement in Red Clay on the Chinese Loess Plateau[J]. 中国科学院青藏高原研究所,2020,538.
APA	Ye, Chengcheng,Yang, Yibo,Fang, Xiaomin,Zan, Jinbo,Tan, Mengqi,&Yang, Rongsheng.(2020).Chlorite weathering linked to magnetic enhancement in Red Clay on the Chinese Loess Plateau.PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,538.
MLA	Ye, Chengcheng,et al."Chlorite weathering linked to magnetic enhancement in Red Clay on the Chinese Loess Plateau".PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY 538(2020).