1. Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China)), Ministry of Education, School of Petroleum Engineering, China University of Petroleum (East China), Qingdao 266580, China
2. PetroChina Bohai Drilling Engineering Co. LTD, Tianjin 300280, China
3. The University of Tulsa, The University of Tulsa Drilling Research Projects, Tulsa, Oklahoma 74104-9700, United States
4. The Second Exploration Team of Shandong Coalfield Geologic Bureau, Jinin 272100, China