Ordos Basin Yanchuan Studies Main Coal Seam Coal Rock Reservoir Characteristics Of The South Block And Capacity Factors Analysis

CBM (Coal seam gas) is a kind of clean energy, witch mainly occurs in the adsorption morphology in coal and rock. Methane is its main components. There are abundant coal resources in China and the expected reserves of Coal bed gas is considerable,so the development of CBM is of great sense just like shooting three birds with one stone. Erdos Basin southern Yanchuan block is one of eight key exploration block of CBM witch is belonged to Sinopec Group. The study area located in the transition zone of The Jin West flexure and The Weibei uplift in construction. Carboniferous, Permian is the main area of coal bearing strata in the area. Its structure is a relatively simple monoclinic structure, there are still some flexure fold in the minority areas. No.2and No.10coal seam is the main target layer of coal seam gas exploration and development, because of their stable distribution, large thickness, moderate buried depth in the research area.Research of coal and rock in the Gao Jiemei area, macroscopical to bright coal and semi bright coal, large specific surface area, porosity and low (average of about3.4%), coal reservoir permeability is relatively poor, No.2and No.10coal seam permeability respectively in0.0124-0.1698md and0.026-0.2265md, central block permeability relative to the high number of main coal seam, coal ash is relatively low, the coalbed methane adsorption favorable. Indoor and field test data and data indicating that the main coal seam gas content is relatively high (13m3/T above), the largest gas content after correction for30m3/T above, gas saturation in85%above, this suggests that the study area main coal seam in the late stage of accumulation suffered little damage. The study area because of the gas main control factors are stress factors, in a certain range, and the gas content is directly proportional to the pressure. The distinction between the East and west two platform, belonging to different pressure systems (pressure coefficient:West,0.76-0.87MPa/100M; East,0.40-0.48MPa/100M). To make a long story short, through a large number of production test data and the data we can see, Yanchuan area south of exploration target layer (2,10) exploration and development is the favorable area for commercial development of potential zone and. According to the research data, the study area coal seam gas overall resource estimation in525.22108m-3,where the number2coal total resources quantity is more than3times.According to the parameters of reservoir evaluation, the coal reservoirs in research area are finally divided into three categories:favorable area, the more favorable area, adverse area. Favorable area is located in the middle of the area. It is currently the most potential area, whitch occupies a large proportion the resource quantity (occupies38%total resources quantity of the No.2coal). On the basis of the comprehensive analysis and study to the coal reservoirs and the capacity control factors in the research area we draw the conclusion:there is a relatively large commercial development potential in the block,and to the key zones for development we should take the first type favorable area in the central block for the orientation and expand to the relatively favorable area in the north west direction,based on the central area.