1. State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, Shaanxi 710069, China
2. Key Laboratory for Geo-Hazards in Loess Area, Ministry of Land and Resources, Xi’an Center of China Geological Survey, Xi’an, Shaanxi 710054, China
3. Shaanxi Hydraulic Environment Investigation Center, Xi’an, Shaanxi 710069, China