Storage rule and controlling factors of coalbed gas in Zhaoguan mine field of Huanghebei coalfiled

Storage rule and controlling factors of coalbed gas in Zhaoguan mine field were analyzed on the basis of the generation, storage and migration theory of coalbed gas in combination with the data of geological exploration and mine production. From research on the regional geological evolution, coal generating and storing capacity and lithologic characteristics, geological structure, burial depth, bedrock thickness, hydrogeological conditions and magmatic intrusion, it was found that underground hydrodynamic conditions and magmatic intrusion events are the controlling factors of coalbed gas storage in the mine. Underground hydrodynamic conditions had obvious effect, shallow hydrodynamic conditions were manifested mainly as migration and escape and were unfavorable to the conservation of coalbed gas. The deep hydrodynamic conditions were presented mainly as sealing and blockage, advantageous to the storage of gas. The manner and degree of magmatic intrusion of coal seams were the major controlling factors resulting in the lower gas content in seam 11 and 13 than that in seam 7 and 10.