干旱区生态环境知识资源中心(Arid): 渭河流域典型黄土剖面的环境磁学特征及其古气候意义

Arid

	渭河流域典型黄土剖面的环境磁学特征及其古气候意义
其他题名	Typical Loess/Paleosol Sequences in Weihe Drainage Areas: Environmental Magnetism Features and Paleoclimate Interpretation
	贾佳 1; 夏敦胜 2; 金明 1; 王训明 2; 魏海涛 1; 刘现斌 1
来源期刊	冰川冻土
ISSN	1000-0240
出版年	2010
卷号	32 期号:1 页码:91-97
中文摘要	对黄土高原南部耀县全新世黄土地层的形成及保存环境进行了研究. 结果表明: 地层中磁性矿物主要为软磁性矿物, 硬磁性矿物对地层的磁学性质贡献小; 随着成壤强度的增加, 硬磁性矿物的相对含量在减少. 本区全新世地层的形成和保存环境为氧化环境, 适宜用磁学手段反演全新世古气候. 对磁化率和频率磁化率、无磁滞剩磁磁化率的对比分析, 可以看出: 成壤强度较低时, 细粒磁性矿物相对于磁性矿物总量的增加速率相对较快; 成壤强度较高时, 细粒磁性矿物的相对含量会达到或趋近饱和, 相对于磁性矿物总量的增加速率相对较慢. 研究表明, 在黄土地层中, chifd%和chiARM/chi等指示细粒磁性矿物的磁学参数可以显示更细微的气候变化; 在古土壤中, chilf的气候指示意义相对更好.
英文摘要	The Loess Plateau, covered with aeolian sediments called loess, lies in the north of East Asian monsoon areas. Previous studies indicated that the loess deposits are an excellent archive of palaeo-environmental information, which may provide some of the most complete continental records of climate change. Environment magnetism is one of common substitute parameters of paleoclimate, including chilf, chifd%, chiARM, chiARM/chi, SIRM, SIRM/chi, Hcr, and Hc and so on. But the recent studies have showed that the chilf not always relate positively to humidity, and the reductive-oxidative conditions maybe infect it. In the south of Loess Plateau, some loess profiles also have this phenomenon. In this paper, a study is presented, which choices the Yaoxian profile as the research object. The profile is located in the south of the Loess Plateau. The environment magnetism parameters showed the soft magnetism mineral controlling the sample’s property, and the pedogenesis being negative relation to the content of hard magnetism mineral. This relation is more approximate to the typical loess profiles in Loess Plateau. Thus, the Yaoxian profile is considered forming and saving in an oxidative condition. Comparing the differences of chilf, chifd% and chiARM/chi curves’ changes in loess and paleosol stratum discovers that the increasing rate of fine magnetic grain mineral relative to the total content of magnetized mineral is much pronounced in weak pedogenesis loess stratum. Thus, the chifd% and chiARM/chi are much useful to recover the paleoclimate in arid period, but the chilf , rather than chifd% and chiARM/chi, is much useful to recover the paleoclimate in humid period.
中文关键词	磁学参数 ; 黄土 ; 耀县剖面
英文关键词	magnetic parameters loess Yaoxian profile
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:3822490
来源机构	中国科学院西北生态环境资源研究院 ; 兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/224696
作者单位	1.兰州大学, 西部环境教育部重点实验室, 兰州, 甘肃 730000, 中国; 2.中国科学院,寒区旱区环境与工程研究所, 沙漠与沙漠化重点实验室, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	贾佳,夏敦胜,金明,等. 渭河流域典型黄土剖面的环境磁学特征及其古气候意义[J]. 中国科学院西北生态环境资源研究院, 兰州大学,2010,32(1):91-97.
APA	贾佳,夏敦胜,金明,王训明,魏海涛,&刘现斌.(2010).渭河流域典型黄土剖面的环境磁学特征及其古气候意义.冰川冻土,32(1),91-97.
MLA	贾佳,et al."渭河流域典型黄土剖面的环境磁学特征及其古气候意义".冰川冻土 32.1(2010):91-97.