Directional arrangement of phyllite fragments in phyllite talus slopeat the eastern margin of the Tibetan Plateau  

作　　者：WAN Yu-hao ZHAO Xiao-yan LING Si-xiang LI Jin ZENG Cai-yun BERND Wünnemann 

机构地区：[1]Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China

出　　处：《Journal of Mountain Science》2021年第11期3069-3081,共13页山地科学学报（英文）

基　　金：This study has been supported by the National Natural Science Foundation of China(Grant No.41672295);Science and Technology Project of Department of Transportation of Sichuan Province(Grant No.2015B1-1);Sichuan Provincial Science and Technology Plan Project(Grant No.2017JY0264);Scientific and Technological Research and Development Plan of China Railway Corporation(Grant No.P2018G047).

摘　　要：Phyllite fragments are essential for accumulating and generating talus slope at the toes of hillslopes,however,how they are linked to slope failure remains unknown.This paper reports the directional arrangement of phyllite fragments(DAPF)in phyllite talus slope at the eastern margin of the Tibetan Plateau.Field investigation,mathematical statistics and model experiments were performed in order to systematically understand the influencing factors,which include fragment shape,flat ratio,dip angle(α),and fine particle content(c).The results show that the quadrilateral fragmentgenerates a similar imbricate structure more easily than the triangular and rod fragments in the phyllite talus slope.Additionally,the flat phyllite fragments easily accumulate as imbricated structures on the phyllitetalus slope.When the dip angle(α)is in the range of 20°–30°,the minimum orientation ratio(P)is more than 50%,which means thatthe DAPF phenomenon is more obviousin the phyllite talus slope.For the fine particle content(c)at the same dip angle(α),the minimum orientation ratio(P)is 54%,and the minimum orientation ratio(P)correlates positively with the fine particle content(c).Therefore,compared with the homogeneous talusslope,the phyllite talusslopedisplays a special DAPF phenomenon.This study provides a valuable reference and presents novel knowledgefor risk assessment and engineering design against the phyllite talus slope failure mechanism.

关 键 词：Phyllitefragment Talus slope Directional arrangement Physical model experiment Field investigation 

分 类 号：P588.3[天文地球—岩石学] TU45[天文地球—地质学]