Study On The Occurrence Regularity Of CBM At Eastern Urumqi River Mining Area In Southern Junggar Basin

Eastern Urumqi River coal mining area has many coal seams, large thickness of coal seam,low coal rank. Its CBM parameters is representative in Xinjiang. This article choosing the mining area to study its CBM occurrence regularity and resource potential has important practical significance for low coal rank CBM resource evaluation and exploration in Xinjiang.Through indoor and outdoor information collection, investigation on site, sampling and testing analysis, application of CBM geology, Coal petrology, Sedimentology, Geochemistry,Coal geology’s theories and methods discusses and studies CBM content of coal seam,adsorption and coal reservoir physical characteristics of the coal mining area, and more deeply expounds the conditions for the occurrence and development of CBM. This article also discusses the geological structure, deposition, coal metamorphism, effective burial depth, the roof and floor lithology, rock and coal quality characteristics, hydro-geological conditions’ s impact on the occurrence of CBM.Through research it shows that Jurassic Xishanyao group and Badaowan group are mainly coal-bearing strata of the mining area, to the west of 41 line Xishanyao group more developed, to the east of 41 line badaowan group is more developed. Because of many coal seam layers, large coal seam thickness, coal seam wide distribution, it has a good potential for gasing and sealing CBM ability. Coal reservoir has good generating and adsorption. CBM content increases with burial depth increasing, with the maximum reflectance of vitrinite increasing, with the beneficial coal seam thickness increasing. The reservoir pressure, the permeability of reservoir petrophysical conditions are more conducive to the development of CBM, but there is big difference in different regions, fully showing that the heterogeneity of coal seam. Geological tectonics, sedimentation, roof and floor rock properties, hydrological geological conditions are conducive to the preservation of CBM. Comprehensive analysisshows that Xishanyao group is better than Badaowan group regardless of CBM gasing or storage conditions; Under CBM weathering zone of the northern monoclonal no f1 normal fault developing area and Badaowan syncline are the coalbed gas storage better area, among them, the CBM concent in the southern wing may be better than in the northern wing of Badaowan Syncline, Badaowan syncline core has the maximum CBM content in this mining area.According to "CBM resources / reserves specification"(DZ/T0216-2010), using the the volume method estimates that this mining area coalbed methane resources / reserves is 531.04×10~8m~3. It is a large CBM field. It has a good development prospect.