1. Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education, China University of Mining and Technology, Xuzhou 221116, China
2. School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China
3. School of Geology and Mining Engineering, Xinjiang University, Urumqi 830017, China
4. Far East Geological Institute, Far Eastern Branch of the Russian Academy of Sciences, 690022 Vladivostok, Russia