1. Land and Resources Research Center, Mianyang Normal University, Mianyang 621000, China
2. Sichuan Key Laboratory of Geoscience and Nuclear Technology, Chengdu University of Technology, Chengdu 610059, China
3. Earth Exploration and Information Technology Key Laboratory of Ministry of Education, Chengdu University of Technology, Chengdu 610059, China
4. College of Earth and Planetary Sciences, Chengdu University of Technology, Chengdu 610059, China