1. School of Petroleum and Gas Engineering; Southwest Petroleum University; Chengdu 610500 Sichuan China
2. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation; Southwest Petroleum University; Chengdu 610500 Sichuan China
3. Chuanxi Drilling Company, Chuanqing Drilling Engineering Company, Limited, China National Petroleum Corporation; Chengdu 610015 Sichuan China