1. College of Earth Sciences & Engineering, Shandong University of Science and Technology, Qingdao 266590, China
2. Key Laboratory of Coalbed Methane Resource & Reservoir Formation Process, Ministry of Education, China University of Mining and Technology, Xuzhou 221008, China
3. School of Resources and Earth Science, China University of Mining and Technology, Xuzhou 221116, China
4. Department of Earth and Environment Sciences, University of Texas at Arlington, Arlington, Texas 76019, United States
5. Nottingham Geospatial Institute, Faculty of Engineering, University of Nottingham, Nottingham NG7 2TU, U.K.