A new method to constrain soil development time using both OSL andradiocarbon dating

doi:10.1016/j.geoderma.2015.07.004}

	A new method to constrain soil development time using both OSL andradiocarbon dating
	Liu,XD(Liu,Xiaodong)2; Miao,XD(Miao,Xiaodong)3; Wang,H(Wang,Hong)3; Hanson,P R(Hanson,Paul R)4; Mason, J A(Mason, Joseph A)1; Miao,Xiaodong
刊名	Geoderma
	2016
卷号	261 期号:2016 页码:93-100
关键词	Soil Development Time Optically Stimulated Luminescence Dating Radiocarbon Dating Pyrolysis–combustion Low Molecular Weight (Lmw) Organic Compound
DOI	10.1016/j.geoderma.2015.07.004}
文献子类	期刊论文
英文摘要	The time over which a soil has developed since the parent materials were deposited and subaerially exposed, referred to here as soil development time, is of considerable interest to pedologists, geomorphologists, geologists, archeologist, and paleoclimatologists. Soil development time has been estimated both indirectly, based on the degree of soil development, and directly, by radiocarbon dating of soil organic matter, optically stimulated luminescence (OSL) dating of parent material deposition, and through exposure dating using cosmogenic nuclides. Here we propose a new model for estimating the soil development time by subtracting the low molecular weight (LMW) or pyrolysis-volatile 14C age of the uppermost A horizon of a soil from the OSL age of the C horizon of the parent material [soil time = OSL age(parent C horizon) − 14C age(LMW fraction of uppermost A horizon)]. The LMW organic compound fraction represents the most mobile carbon compounds in the soil organic carbon pool, and is least resistant to physical, chemical, and biodegradation in the soil environment, potentially yielding the youngest 14C age. OSL dating of the C horizon provides an estimate of the time since deposition of unconsolidated parent material. Thus, the difference in the two ages can be used to estimate the time that has elapsed for pedogenic alteration from deposition of the parent material to the most recent additions of soil organic carbon. We applied this new approach in four scenarios: (1) in a modern soil that developed downward in loess; (2) in a buried soil developed in aggrading loess (a cumulative soil which grows upward); (3) in a buried soil formed in dune sand; and (4) in a counterexample showing that simple subtraction is not always appropriate because of changes in soil's parent materials from loess to sand. These case studies reveal that this approach constrains soil development time more reasonably than can be commonly done with either OSL or radiocarbon dating alone. The difference in 14C ages between the uppermost and lowermost sola of a soil profile almost certainly underestimates the time of soil development, and the difference in OSL ages taken from sediment units overlying and underlying a buried soil most likely overestimates it. A combination of OSL and radiocarbon dating better constrains soil development time, broadening the applications of these two dating methods beyond their use for cross-checking the accuracy of the other dating method.
项目编号	KZZD-EW-TZ-03 ; 41290255
语种	英语
资助机构	CAS/SAFEA International PartnershipProgram for Creative Research Teams ; CAS/SAFEA International PartnershipProgram for Creative Research Teams ; National Natural Science Foundation of China ; National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.ieecas.cn/handle/361006/5871]
专题	地球环境研究所_古环境研究室
通讯作者	Miao,Xiaodong
作者单位	1.Department of Geography, University of Wisconsin-Madison, Madison, WI 53706, USA 2.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China 3.Illinois State Geological Survey, Prairie Research Institute, University of Illinois at Champaign-Urbana, Champaign, IL 61820, USA 4.School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
推荐引用方式 GB/T 7714	Liu,XD,Miao,XD,Wang,H,et al. A new method to constrain soil development time using both OSL andradiocarbon dating[J]. Geoderma,2016,261(2016):93-100.
APA	Liu,XD,Miao,XD,Wang,H,Hanson,P R,Mason, J A,&Miao,Xiaodong.(2016).A new method to constrain soil development time using both OSL andradiocarbon dating.Geoderma,261(2016),93-100.
MLA	Liu,XD,et al."A new method to constrain soil development time using both OSL andradiocarbon dating".Geoderma 261.2016(2016):93-100.