气候变化领域集成服务门户(CCPortal): Superparamagnetism of two modern soils from the northeastern Pampean region, Argentina and its paleoclimatic indications

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DOI	10.1111/j.1365-246X.2010.04786.x
	Superparamagnetism of two modern soils from the northeastern Pampean region, Argentina and its paleoclimatic indications
	Liu, Qingsong; Torrent, Jose; Morras, Hector; Hong, Ao; Jiang, Zhaoxia; Su, Youliang
通讯作者	Liu, QS (通讯作者)
发表日期	2010
ISSN	0956-540X
起始页码	695
结束页码	705
卷号	183 期号:2
英文摘要	P>The magnetic susceptibility (chi) carried by pedogenic fine-grained ferrimagnets has been widely used as paleoclimatic proxy to elucidate long-term paleoclimatic variations for wind-blown terrestrial loess/paleosol sequences. However, the magnetic properties of the lithogenic parent material can mask the pedogenic signals. In this study, we systematically investigated the origin of the superparamagnetism of two modern soils from the northeastern humid Pampean region, Argentina, developed on loess materials of different mineralogical composition. The samples were treated with the citrate-bicarbonate-dithionite (CBD) reagent, which is known to dissolve the submicron, pedogenic ferrimagnets while leaving unaltered the coarse grained ones. The magnetic material accounting for the frequency-dependent magnetic susceptibility peak at about 50 K remained in the residuals and is independent of the pedogenic processes. In addition, pedogenic ferrimagnetic particles in the two soils have a magnetic signature comparable to that of the soils from the Chinese Loess Plateau. It is also suggested that the chi for the bulk samples does not seem to be a reliable paleoclimatic proxy for the Pampean soils investigated in this study. Instead, the CBD-soluble magnetic signals could be more useful to detect paleoenvironmental variations in this region. These new findings provide improved understanding of the magnetic assemblage in the Pampean loess soils and make it feasible to retrieve the paleoclimatic signals carried by the pedogenic, CBD-soluble, iron oxides after removing the effects of the lithogenic inputs.
关键词	LOESS-PALEOSOL SEQUENCES BICARBONATE-DITHIONITE EXTRACTION FINE-GRAINED MAGNETITE CHINESE LOESS FREQUENCY-DEPENDENCE AC SUSCEPTIBILITY LATE QUATERNARY ALASKAN LOESS BUENOS-AIRES ROCK MAGNETISM
英文关键词	Rock and mineral magnetism
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000283172100014
来源期刊	GEOPHYSICAL JOURNAL INTERNATIONAL
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/257799
推荐引用方式 GB/T 7714	Liu, Qingsong,Torrent, Jose,Morras, Hector,et al. Superparamagnetism of two modern soils from the northeastern Pampean region, Argentina and its paleoclimatic indications[J]. 中国科学院青藏高原研究所,2010,183(2).
APA	Liu, Qingsong,Torrent, Jose,Morras, Hector,Hong, Ao,Jiang, Zhaoxia,&Su, Youliang.(2010).Superparamagnetism of two modern soils from the northeastern Pampean region, Argentina and its paleoclimatic indications.GEOPHYSICAL JOURNAL INTERNATIONAL,183(2).
MLA	Liu, Qingsong,et al."Superparamagnetism of two modern soils from the northeastern Pampean region, Argentina and its paleoclimatic indications".GEOPHYSICAL JOURNAL INTERNATIONAL 183.2(2010).