Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles

doi:10.1016/j.catena.2020.105053

	Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles
	He, Tong 1; Sun, Youbin 2; Gray, Jessica 3; Gu, Ying 3
刊名	CATENA
	2021-03-01
卷号	198 页码:9
关键词	Fe provenance Fe speciation Fe/Mg ratio Fe-Mg substitution Precipitation proxy Asian monsoon Desert-loess transitional zone
ISSN号	0341-8162
DOI	10.1016/j.catena.2020.105053
通讯作者	He, Tong(hetong@nuist.edu.cn)
英文摘要	Determining the categories and content of Fe containing silicate minerals in the desert soils and sediments of northern China is important for understanding the Fe cycle and for correctly interpreting the paleoenvironmental signals from the Loess Plateau downwind. Using a mineral liberation analyzer (MLA), we established the modal mineral abundances of a complete set of Fe containing mineral species in the fine sand to silt fractions of surface samples from Chinese deserts. Results show that the most common discrete particles containing Fe are the silicate phases (similar to 15 wt%), while the weathering product (i.e., Fe oxides) phases are minor and their abundances vary greatly (0.38-4.15 wt%). The degree of weathering has a substantial particle size dependence. The fine fraction (5-20 mu m) generally has a relatively low Fe/Si ratio, possibly due to weathering, while the Fe/Si ratio of the coarse fractions (20-45 mu m, 45-63 mu m, 63-75 mu m, and >75 mu m) are relatively invariant. Abundant Fe is contained within the coarse fractions, which are associated with the local geology. The strong relationship between the Fe and Mg bound within the silicate phases further supports the conclusion that the correlated deviations in the Fe/Si and Mg/Si ratios originate from the provenance bedrock (i.e., siliciclastic, low-grade metamorphic, and possibly high-grade metamorphic, rocks). Since Mg tends to be easily removed during weathering, the Fe/Mg ratios of silicate species largely reflect the weathering intensity. We used the regression equation for the relationship between the local precipitation amount and the Fe/Mg ratios of the soils to produce a novel precipitation proxy. Compared with classical provenance studies conducted using coarse sand and larger rock fragments, the MLA methodology is more applicable to the fine sand and silt fractions; thus, it contributes to the development of weathering and provenance indices based on geochemistry and mineralogy.
资助项目	National Science Foundation of China[41877284] ; National Science Foundation of China[41303071]
WOS关键词	CHEMICAL-WEATHERING HISTORY ; NORTHERN CHINA ; LOESS PLATEAU ; MA ; EVOLUTION ; DEPOSITS ; SEM ; TEM
WOS研究方向	Geology ; Agriculture ; Water Resources
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000605337000050
资助机构	National Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.ieecas.cn/handle/361006/15888]
专题	地球环境研究所_古环境研究室
通讯作者	He, Tong
作者单位	1.Nanjing Univ Informat Sci & Technol, Sch Geog Sci, Nanjing 210044, Peoples R China 2.Chinese Acad Sci, Inst Earth Environm, Xian 710061, Peoples R China 3.Queensland Univ, Julius Kruttschnitt Mineral Res Ctr JKMRC, Brisbane, Qld, Australia
推荐引用方式 GB/T 7714	He, Tong,Sun, Youbin,Gray, Jessica,et al. Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles[J]. CATENA,2021,198:9.
APA	He, Tong,Sun, Youbin,Gray, Jessica,&Gu, Ying.(2021).Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles.CATENA,198,9.
MLA	He, Tong,et al."Provenance of Fe in Chinese Deserts: Evidence from the geochemistry and mineralogy of soil particles".CATENA 198(2021):9.