1. Professor, School of Geological Engineering and Surveying, Chang’An Univ., Xi’an 710054, P. R. China; Key Laboratory of Western China Mineral Resources and Geological Engineering, Xi’an 710054, P. R. China.
2. Professor, School of Geological Engineering and Surveying, Chang’An Univ., Xi’an 710054, P. R. China; Key Laboratory of Western China Mineral Resources and Geological Engineering, Xi’an 710054, P. R. China (corresponding author).
3. Professor, China Institute of Geological Environment Monitoring, Beijing 100081, P. R. China.
4. Ph.D. Candidate, School of Geological Engineering and Surveying, Chang’An Univ., Xi’an 710054, P. R. China; Key Laboratory of Western China Mineral Resources and Geological Engineering, Xi’an 710054, P. R. China.