1. College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China
2. Key Laboratory of Xinjiang Coal Resources Green Mining Ministryof Education, Xinjiang Institute of Engineering, Urumqi 830023, China
3. Cllege of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
4. Xinwen Mining Group Co., Ltd., Tai’an 271000, China
5. CNOOC EnerTech-Drilling & Production Co., Tianjin 300452, China