干旱区生态环境知识资源中心(Arid): 昆仑山北坡黄土粒度特征与环境意义初探

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	昆仑山北坡黄土粒度特征与环境意义初探
其他题名	Grain-size characteristics of Kunlun Mountains loess and its environmental implication
	柳加波; 温仰磊; 赵爽; 李冠华; 贾佳; 魏海涛; 夏敦胜
来源期刊	地球环境学报
ISSN	1674-9901
出版年	2014
卷号	5 期号:2 页码:76-84
中文摘要	昆仑山北坡沉积了极端干旱区巨厚的黄土,不仅记录了塔克拉玛干沙漠的发生发展过程,也蕴含了西风环流的演化信息。该地区气候干旱,成壤作用弱,靠近物源,黄土记录了沉积时的粒度特征,是研究风动力变化的良好载体。本文选取昆仑山北坡的普鲁剖面进行详细的粒度分析,结果表明黄土颗粒较粗,是沙漠的近源沉积,搬运动力较强。通过粒级-标准偏差变化计算,黄土粒度可以分为粉砂(<36 mum)和细砂(〉36 mum)两个敏感粒级组分。依据塔里木盆地内的现代环流特征,粉砂组分主要与近地面较弱的环流风场有关,而细砂组分主要由盆地南缘频发的沙尘暴搬运,并且沙尘暴对沙尘的搬运作用可能更为显著。
英文摘要	The Kunlun Mountains loess, depositing on the southern of Tarim basin where formed the extensive Taklimakan desert, have recorded evolutions of desert and wind power. Although the loess here has great potential in paleoclimate research, much less studies have been done by contrast with China Loess Plateau. In this paper, we discuss bulk grain-size at length on a 29 m profile locate in the northern slope of Kunlun Mountains. The results illustrate that Kunlun Mountains loess is much coarser than other areas and its medium diameter (Md) changes about from 32 mum to 50 mum, which is mainly due to closing to the Taklimakan desert and weak pedogenesis. Previous researches have indicated that the Taklimakan desert tend to be steady since the Late Quaternary, and this could be inferred from the slight fluctuation of grain-size in this profile. Consequently, we attribute fluctuation of grain-size in this profile to wind power changes. Based on calculating standard deviation of each grain-size class, we identify two sensitive sedimentary components, silty sand group whose grain-size is less than 36 mum, and fine sand group whose grain-size is over 36 mum. As different strength of wind power has different transporting capacity, the silty sand (<36 mum) group is more likely carried by weak prevailing wind, and fine sand (>36 mum) group is carried by frequent sand storm. Moreover, the sand storm may play a more important role in dust transporting than we used to realised in Southern Taklimakan desert, but which still need to be further studied.
中文关键词	昆仑山黄土 ; 粒度 ; 敏感组分
英文关键词	Kunlun Mountains loess grain-size sensitive fraction
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:5291642
来源机构	兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/230949
作者单位	兰州大学,干旱环境与气候变化协同创新中心, 西部环境教育部重点实验室, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	柳加波,温仰磊,赵爽,等. 昆仑山北坡黄土粒度特征与环境意义初探[J]. 兰州大学,2014,5(2):76-84.
APA	柳加波.,温仰磊.,赵爽.,李冠华.,贾佳.,...&夏敦胜.(2014).昆仑山北坡黄土粒度特征与环境意义初探.地球环境学报,5(2),76-84.
MLA	柳加波,et al."昆仑山北坡黄土粒度特征与环境意义初探".地球环境学报 5.2(2014):76-84.