College of Geology and Environment;
Xi'an University of Science and Technology;
Xi'an 710054;
China;
Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation;
Xi’an 710054;
China;
Post-doctoral Research Station of Geological Resources and Geological Engineering;
Xi'an University of Science and Technology;
Xi'an 710054;
China;
Geological Research Institute for Coal Green Mining;
Xi'an Universityof Science and Technology Xi'an 710054;
China;
Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process;
Ministry of Education;
China University of Mining and Technology;
Xuzhou 221116;
China;
coalbed; methane; reservoir; characterization; pore; structure; relative; permeability; nuclear; magnetic; resonance;