The Correlation between of Magnetic Fabric and the Grain Size Parameters Characteristics of Aeolian Sediment in the Middle Reaches of Yangtze River
In order to establish aeolian sediments identification markers in the middle reaches of Yangtze River,we studied the magnetic fabric and grain size characters of the aeolian sediments.The contrastive analysis between magnetic fabric character and grain size parameter of sand-dune along the riverbank from JiangXi to WuHan reveals that:(1)The main grade of the sand-dune sediments in the middle reaches riverbank of Yangtze River are composed of sand (up to 93-95%),and most of which are middle-size sand and fine sand with little clay.Due to the difference of wind power and wind velocity in different area,there are obviously difference in sediment grain-size components and mean grade size;(2)in the profile of dust-sand,grain size of clayey layer is mainly composed of sand and silty sand components(sand up to 59.62%,silty sand up to 33.96%),and it also contains coarse sand components and clay components.In Qingshan,WuHan,the loess layer in the bottom of sand-dune,is mainly composed of silty sand (up to 50.95%),and the content of clay (17.46%) are much high compared with sand layer;(3)the skewness coefficient of most samples of aeolian sediment is positive and its distribution mainly consists of proximity symmetry and positive skewness.The sorting grades of most specimens range from good sorting to bad sorting,and the sorting of sand-dune in XinGang,JiangXi is better than the sorting in Qingshan,WuHan,and the worst sorting grade(accounting for 72.6%) is in the bottom of the sand-dune in WuHan.The fundamental shape of frequency curve is unimodal and the curve is middling kurtosis,but sand-dune in XinGang,JiangXi,the fundamental shape of the curve is bimodal indicating that there are two obvious grain-sizes components;(4)the high value of susceptibility corresponds to the clayey layer,and the low value corresponds to the sand in sand-dunk sediment.The value P,F,L and q of magnetic fabric parameters in sand are higher than the relative value in clayey;(5)The magnetic fabric parameters Fs,p have a positive correlation with mean grain-size (Mz) and the standard deviation (St),but have a negative correlation with the skewness coefficient (Sk) and the kurtosis coefficient (Kg).
aeolian sediment grain size character magnetic fabric character correlation
Yufen Zhang Changan Li Liang Chen Chunguo Kang Xilin Sun Yong Yang
Institute of Geophysics and Geomatic, China University of Geosciences, Wuhan, PRC Faculty of Earth Sciences, China University of Geosciences, Wuhan, PRC;State Key Laboratory of Bioge Faculty of Earth Sciences, China University of Geosciences, Wuhan, PRC
国际会议
长沙
英文
414-421
2012-06-15（万方平台首次上网日期，不代表论文的发表时间）