气候变化领域集成服务门户(CCPortal): Critical Altitudinal Shift From Detrital to Pedogenic Origin of the Magnetic Properties of Surface Soils in the Western Pamir Plateau, Tajikistan

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DOI	10.1029/2019GC008752
	Critical Altitudinal Shift From Detrital to Pedogenic Origin of the Magnetic Properties of Surface Soils in the Western Pamir Plateau, Tajikistan
	Kang, Jian; Zan, Jinbo; Bai, Yan; Fang, Xiaomin; Chen, Chihao; Guan, Chong; Khodzhiev, Amriddin
通讯作者	Zan, JB ; Bai, Y (通讯作者)
发表日期	2020
EISSN	1525-2027
卷号	21 期号:2
英文摘要	Sedimentary archives of the westerlies-influenced Pamir Plateau in Tajikistan, a climatically sensitive region in arid central Asia, provide information on past climatic changes and the tectonic evolution of the northern Tibetan Plateau. However, due to the scarcity of meteorological stations, knowledge of the recent precipitation history of the region is limited. We conducted a detailed rock magnetic investigation of 34 surface loess samples from the western Pamir Plateau. The results show that on the windward side, below an altitude of 2,000-2,200 m above sea level, the concentration of magnetic minerals initially decreases and then begins to increase with increasing altitude. Below 2,000-2,200 m above sea level, the surface soils are enriched in multidomain magnetite particles, suggesting a detrital origin of the magnetic minerals, whereas above this altitude the samples are enriched in fine superparamagnetic magnetite/maghemite grains of pedogenic origin. The inferred variations in pedogenic intensity, combined with analysis of the available meteorological data and the content of organic matter and clay, support the occurrence of an altitudinal threshold separating a predominantly detrital control on surface soil magnetic mineral assemblages from a predominantly pedogenic control. Within the plateau interior, the surface loess samples exhibit low and uniform values of magnetic concentration parameters and organic matter and clay content, which is attributed to the decreased supply of moisture from westerly sources because of the rain shadow effect. Our results indicate that rock magnetic investigations can be used to define a critical climatic boundary in arid central Asia.
关键词	REVERSAL CURVE DIAGRAMS CHINESE LOESS PLATEAU CENTRAL-ASIA SUSCEPTIBILITY VARIATIONS ACQUISITION CURVES CLIMATE ENHANCEMENT TEMPERATURE VARIABILITY PALEOSOL
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000534477700032
来源期刊	GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
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/259857
推荐引用方式 GB/T 7714	Kang, Jian,Zan, Jinbo,Bai, Yan,et al. Critical Altitudinal Shift From Detrital to Pedogenic Origin of the Magnetic Properties of Surface Soils in the Western Pamir Plateau, Tajikistan[J]. 中国科学院青藏高原研究所,2020,21(2).
APA	Kang, Jian.,Zan, Jinbo.,Bai, Yan.,Fang, Xiaomin.,Chen, Chihao.,...&Khodzhiev, Amriddin.(2020).Critical Altitudinal Shift From Detrital to Pedogenic Origin of the Magnetic Properties of Surface Soils in the Western Pamir Plateau, Tajikistan.GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS,21(2).
MLA	Kang, Jian,et al."Critical Altitudinal Shift From Detrital to Pedogenic Origin of the Magnetic Properties of Surface Soils in the Western Pamir Plateau, Tajikistan".GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS 21.2(2020).