干旱区生态环境知识资源中心(Arid): Loess-palaeosol sequences in diverse environments: Aeolian accumulation identification and magnetic susceptibility models

Arid

DOI	10.1016/j.palaeo.2021.110683
	Loess-palaeosol sequences in diverse environments: Aeolian accumulation identification and magnetic susceptibility models
	Liu, Xiuming; Mao, Xuegang
通讯作者	Mao, XG (corresponding author), Fujian Normal Univ, Inst Geog, Fuzhou 350007, Peoples R China.
来源期刊	PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
ISSN	0031-0182
EISSN	1872-616X
出版年	2021
卷号	584
英文摘要	The thick loess-palaeosol sequences of the Chinese Loess Plateau (CLP) are valuable continental archives of paleoclimatic and paleoenvironmental changes since at least the mid-Miocene. The magnetic susceptibility record of loess sequences is frequently used for palaeoclimatic reconstruction. However, the two magnetoclimatological models for the magnetic enhancement of loess-palaeosol sequences-the wind vigour model and the pedogenic model-are still debated, and neither model alone is sufficient to explain the magnetic susceptibility stratigraphy of loess deposits in diverse environments. Loess can be substantially altered by its environment of deposition and the macroscopic characteristics of loess may differ substantially from the welldocumented sequences of the CLP, which complicates loess identification and its palaeoclimatic interpretation. In the present study, we summarize the attributes of loess deposits in different environments and review possible approaches for identifying aeolian accumulation. Loess-palaeosol sequences in various climatic contexts, from arid to subhumid, are summarized and categorized and the relationship between the magnetic susceptibility and effective precipitation is evaluated. A model comprising three cases is proposed to interpret the magnetic susceptibility of loess-palaeosol sequences in a variety of different environments. In case A (e.g., the Xinjiang loess, NW China), where physical weathering dominates and pedogenesis is weak, there is no relationship between the magnetic susceptibility and pedogenesis, and here the wind vigour model is applicable. In case B (e.g., the CLP), where, under predominantly oxidizing conditions, the magnetic susceptibility increases with pedogenic intensity, and an oxidizing-pedogenic model is applicable. In case C (e.g., Alaskan and Siberian loess), there is a negative relationship between magnetic susceptibility and pedogenesis due to the dissolution of detrital iron oxides under reducing conditions, and a reduction-pedogenesis model is applicable. In Case C, pedogenesis (or chemical weathering/dissolution) acts to largely obliterate the detrital magnetic susceptibility signal. Hence, contrary to the original interpretation of the magnetic susceptibility of Alaskan and Siberian loess, the wind vigour model is not applicable. Two thresholds of mean annual precipitation between the three cases are proposed, which enable the paleoclimatic interpretation of loess magnetic susceptibility records in different environments.
英文关键词	Pedogenesis Wind vigour model Pedogenic model Redox conditions iron oxides
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000709240700003
WOS关键词	EOLIAN RED CLAY ; CHINESE LOESS ; PALEOCLIMATIC RECORDS ; TIBETAN PLATEAU ; SOUTHERN CHINA ; ALASKAN LOESS ; DECCAN TRAPS ; DESERT LOESS ; ORIGIN ; DEPOSITS
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary ; Paleontology
WOS研究方向	Physical Geography ; Geology ; Paleontology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/364283
作者单位	[Liu, Xiuming; Mao, Xuegang] Fujian Normal Univ, Inst Geog, Fuzhou 350007, Peoples R China; [Liu, Xiuming; Mao, Xuegang] Fujian Normal Univ, Minist Sci & Technol & Fujian Prov, State Key Lab Subtrop Mt Ecol, Fuzhou 350007, Peoples R China; [Liu, Xiuming] Macquarie Univ, Dept Earth & Environm Sci, Sydney, NSW 2109, Australia
推荐引用方式 GB/T 7714	Liu, Xiuming,Mao, Xuegang. Loess-palaeosol sequences in diverse environments: Aeolian accumulation identification and magnetic susceptibility models[J],2021,584.
APA	Liu, Xiuming,&Mao, Xuegang.(2021).Loess-palaeosol sequences in diverse environments: Aeolian accumulation identification and magnetic susceptibility models.PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,584.
MLA	Liu, Xiuming,et al."Loess-palaeosol sequences in diverse environments: Aeolian accumulation identification and magnetic susceptibility models".PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY 584(2021).