Magnetic properties of the Tertiary red clay from Gansu Province, China and its paleoclimatic significance

doi:10.1007/BF02875337

IEECAS OpenIR > 黄土与第四纪地质国家重点实验室（1985-2004）

	Magnetic properties of the Tertiary red clay from Gansu Province, China and its paleoclimatic significance
	Liu, XM; An, ZS; Rolph, T; Qiang, XK; Hesse, P; Lu, HY; Zhou, J; Cai, YJ
	2001-07
发表期刊	SCIENCE IN CHINA SERIES D-EARTH SCIENCES
卷号	44 期号:7 页码:635-651
文章类型	Article
摘要	The study on magnetic properties of the red clay indicates that the red clay and loess-paleosol sequence have a common magnetic mineralogy, with magnetite, maghemite, hematite (and possibly goethite) contributing to the magnetic behavior. The red clay magnetic susceptibility is also found to have a positive relation with extrafine superparamagnetic grains. This suggests that, like the Quaternary loess-paleosols, an ultrafine ferrimagnetic component produced during pedogenesis in the red clay under humid conditions also plays an important role in susceptibility enhancement in the soil units. This is supported by the correlation between Rb/Sr ratio and magnetic susceptibility. This signifies that, like the above loess-paleosol sequence, the magnetic susceptibility of the red clay can be used as a general proxy paleoclimatic indicator, although whether its susceptibility in the red clay is comparable to pedogenesis intensity and requires further investigation. Magnetic susceptibility variation in the red clay thus also provides an eolian/pedogenic record of paleoclimatic evolution. Study of the background susceptibility indicates that, on average, the absolute scale of the paleoclimatic shift from red clay development to Quaternary loess deposition is similar to the climatic shift from stage 5 (S1) to stage 2-4 (L1). This may suggest that during the Quaternary there is an evident strengthening of the absolute wind intensity to bring more (about double) coarser and less weathered (non-SP fraction) eolian magnetic input from the source regions to the Loess Plateau than during the Pliocene. The presence of eolian red clay since 7.5 Ma BP in central-northern China implies an important environmental change from the underlying Cretaceous red sandstone. The red clay development was closely related to global drying and climate cooling since the Cretaceous and closely associated with the abrupt uplift of the Qinghai-Xizang Plateau at about that time. This uplift of the plateau intensified the East Asia monsoon system and started red clay deposition.
关键词	red clay magnetic property magnetic susceptibility Rb/Sr ratio paleoclimatic significance
学科领域	Geology
DOI	10.1007/BF02875337
关键词[WOS]	LOESS PLATEAU ; NORTHERN-HEMISPHERE ; MAGNETOSTRATIGRAPHY ; TEMPERATURE ; SEQUENCES ; PALEOMONSOON ; MINERALOGY ; EVOLUTION ; DEPOSITS ; MONSOON
收录类别	SCI ; SCIE
语种	英语
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:000171965800006
出版者	SCIENCE PRESS
引用统计	被引频次：24[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.ieecas.cn/handle/361006/12006
专题	黄土与第四纪地质国家重点实验室（1985-2004）
推荐引用方式 GB/T 7714	Liu, XM,An, ZS,Rolph, T,et al. Magnetic properties of the Tertiary red clay from Gansu Province, China and its paleoclimatic significance[J]. SCIENCE IN CHINA SERIES D-EARTH SCIENCES,2001,44(7):635-651.
APA	Liu, XM.,An, ZS.,Rolph, T.,Qiang, XK.,Hesse, P.,...&Cai, YJ.(2001).Magnetic properties of the Tertiary red clay from Gansu Province, China and its paleoclimatic significance.SCIENCE IN CHINA SERIES D-EARTH SCIENCES,44(7),635-651.
MLA	Liu, XM,et al."Magnetic properties of the Tertiary red clay from Gansu Province, China and its paleoclimatic significance".SCIENCE IN CHINA SERIES D-EARTH SCIENCES 44.7(2001):635-651.