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DOI	10.1016/j.chemer.2011.06.001
	Lanthanide tetrad effect in ferromanganese concretions and terra rossa overlying dolomite during weathering
	Feng, Jin-Liang; Gao, Shao-Peng; Zhang, Ji-Feng
通讯作者	Feng, JL (通讯作者)
发表日期	2011
EISSN	1611-5864
起始页码	349
结束页码	362
卷号	71 期号:4
英文摘要	The lanthanide tetrad effect was investigated in a 5.4m thick terra rossa profile overlying dolomite on the Yunnan-Guizhou Plateau, China. The results demonstrate that the chondrite-normalized rare earth element pattern of dolomite bedrock displays a W-type tetrad effect. The insoluble residue from the dolomite bedrock does not exhibit any significant tetrad effect. In contrast, some ferromanganese concretions and the terra rossa show tetrad effect. It is worth noting that the conjugate M- and W-types of the tetrad effect are observed in some terra rossa samples. The tetrad effect in the ferromanganese concretions and the terra rossa possibly originates from redistribution of dissolved rare earth elements during their downwards movement in the profile and not only from water/rock interaction. Within the dolomite weathering system, the ferromanganese concretions and surrounding terra rossa present similar correlations of Eu/Eu, Y/Ho, Sm/Nd, Ce/Ce, with the size of the tetrad effect. The ferromanganese concretions and the terra rossa with tetrad effect are characterized by a reduced, non-chondritic Y/Ho ratio. Also the Y/Ho ratio exhibits a clear negative correlation with the size of the tetrad effect in the ferromanganese concretions and the terra rossa. In addition, the Eu/Eu* tends to increase with increasing size of the tetrad effect in the ferromanganese concretions and the terra rossa, as does the Sm/Nd ratio. The regular variation for Eu/Eu, Y/Ho and Sm/Nd is likely a result of the fractionation of rare earth elements and yttrium with the tetrad effect. On the other hand, the correlation of the Ce/Ce with the size of the tetrad effect in the ferromanganese concretions and the terra rossa is random. This likely indicates that the Ce behavior within weathering system is mainly controlled by redox condition, rather than tetrad effect. Comparative study indicates that the correlations of Eu/Eu, Y/Ho, Ce/Ce, with the size of the tetrad effect in the ferromanganese concretions and the terra rossa, are not similar to those found in a highly evolved igneous system. Nevertheless, the correlation of Sm/Nd with the size of tetrad effect in weathering system is similar to that in igneous system. In general, it appears to indicate that the tetrad effect occurrence in granitic rocks is not associated with weathering. (C) 2011 Elsevier GmbH. All rights reserved.
关键词	RARE-EARTH-ELEMENT TONO URANIUM DEPOSIT WATER-ROCK SYSTEMS ISOVALENT TRACE-ELEMENTS YUNNAN-GUIZHOU PLATEAU REE PATTERNS W-TYPE PERALUMINOUS GRANITE BAERZHE GRANITES IGNEOUS ROCKS
英文关键词	Dolomite; Weathering; Terra rossa; Ferromanganese concretions; Rare earth elements; Lanthanide tetrad effect; Ce anomaly; Eu anomaly; Y/Ho ratio; Sm-Nd fractionation
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000299463000003
来源期刊	CHEMIE DER ERDE-GEOCHEMISTRY
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/257874
推荐引用方式 GB/T 7714	Feng, Jin-Liang,Gao, Shao-Peng,Zhang, Ji-Feng. Lanthanide tetrad effect in ferromanganese concretions and terra rossa overlying dolomite during weathering[J]. 中国科学院青藏高原研究所,2011,71(4).
APA	Feng, Jin-Liang,Gao, Shao-Peng,&Zhang, Ji-Feng.(2011).Lanthanide tetrad effect in ferromanganese concretions and terra rossa overlying dolomite during weathering.CHEMIE DER ERDE-GEOCHEMISTRY,71(4).
MLA	Feng, Jin-Liang,et al."Lanthanide tetrad effect in ferromanganese concretions and terra rossa overlying dolomite during weathering".CHEMIE DER ERDE-GEOCHEMISTRY 71.4(2011).