1. Ph.D. Candidate, School of Petroleum Engineering, China Univ. of Petroleum (East China), Qingdao 266580, China.
2. Professor, Dept. of Field Development, Northeast Petroleum Branch, Sinopec, Changchun 130062, China.
3. Engineer, China United Coalbed Methane Co. Ltd., No. 21, Jiuxianqiao Rd., Chaoyang District, Beijing 100011, China.
4. Professor, School of Petroleum Engineering, China Univ. of Petroleum (East China), Qingdao 266580, China (corresponding author).