Abstract:
For the models of geological structure compound controlling gas action, taking the stress state and sealing ability of syncline and fault plane as research object, the study found that the stress state of a fault plane reflected concentrative degree of local stress, the fault plays significant role in buffering tectonic stress of a syncline, however, the position of the fault in a syncline's wing determined the difference of gas occurrence and migration law of coalbed methane (CBM). Through the production data from some CBM wells in Pingdingshan No.13 Mine, the paper analyzed the control models and found that it's a low permeability and a high pressure gradient in sealed structure reservoir (
If>4.5), while it had high drainage production for a well nearby structure; the reservoir's permeability was high in fracture zone along principal stress direction, and its migration ability was controlled by occurrence state of CBM in reservoir; the migration law of CBM was determined by sealing ability of reservoir considering the combined effect of geological structure.