1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing 102249, P. R. China
2. Unconventional Oil and Gas Science and Technology Research Institute, China University of Petroleum, Beijing 102249, P. R. China
3. Shale Gas Research Institute, PetroChina Southwest Oil & Gas Field Company, Chengdu 610056, P. R. China
4. Exploration and Development Department, Sichuan Changning Natural Gas Development Co., Ltd., Chengdu 610056, P. R. China
5. Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 834000, P. R. China