*Chenglong Zhang^1,2, Zhenhong Li^1,2,3, Wu Zhu^1,2,4, Mingtao Ding^1,2, Bo Chen^1,2 (1.Chang'an University, College of Geological Engineering and Geomatica,Xi’an, China, 2.Key Laboratory of Loess, Xi’an, China, 3.Key Laboratory of Western China's Mineral Resources and Geological Engineering, Ministry of Education, Xi’an, China, 4.Key Laboratory of Ecological Geology and Disaster Prevention, Ministry of Natural Resources, Xi’an, China)