1. Key Laboratory of Unconventional Oil & Gas Development, China University of Petroleum (East China), Ministry of Education, Qingdao 266580, China
2. School of Petroleum Engineering, China University of Petroleum (East China), Qingdao, Shandong 266580, China
3. College of Mining Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China