1. School of Geology Engineering and Geomatics, Chang’an University, Xi’an 710054, China
2. The Sixth Gas Production Plant, PetroChina Changqing Oilfield Company, Xi’an, Shaanxi 710018, China
3. Sinopec Gas Company, Chaozhou, Guangdong 515700, China
4. Engineering Research Center of Development and Management for Low to Ultra-Low Permeability Oil and Gas Reservoirs in West China, Ministry of Education, College of Petroleum Engineering, Xi’an Shiyou University, Xi’an 710065, China