[1] China Univ Min & Technol, Key Lab Coalbed Methane Resources & Reservoir For, Minist Educ, Xuzhou 221008, Jiangsu, Peoples R China
[2] China Univ Min & Technol, Sch Resources & Geosci, Xuzhou 221116, Jiangsu, Peoples R China
[3] Xian Univ Sci & Technol, Geol Res Inst Coal Green Min, Xian 710054, Shaanxi, Peoples R China
[4] Xian Univ Sci & Technol, Coll Geol & Environm, Xian 710054, Shaanxi, Peoples R China