1.MOE Key Lab of Coalbed Methane Resources and Reservoir Formation Process, Xuzhou , China; 2.School of Resources and Earth Science, China University of Mining and Technology, Xuzhou , China;3.No.6 Geological Brigade, Jiangsu Provincial Bureau of Geology and Mineral, Lianyungang , China

基于滇东老厂矿区发育有多煤层，并具有高地应力特征，且对煤层气的勘探开发具有重要影响，为探究地应力对煤层气开采的影响，通过分析该矿区水力压裂试井数据，探讨了地应力对储层压力、渗透率及超压现象的影响。研究结果表明：老厂矿区煤储层压力中大部分来自于地应力，煤层气属于压力主导型应力气；同时，高地应力对煤层流体能量的贡献相对较大，对维持深部煤层的压力状态起到了重要作用，但也给煤储层改造带来较大困难；各煤层压力系数、地应力梯度在层域上呈现波动性变化，且部分煤层普遍超压；随着最小主应力的增大，煤层渗透率逐渐降低，压力系数逐渐升高；各煤层最小主应力梯度同样表现出波动性，表明各煤层地应力特征有较大差异，这与压力系数所表现出的波动性具有一致性，验证了地应力是老厂矿区多层叠置独立含气系统形成的主要控制因素之一。

Based on Laochang Mining Area of East Yunnan developed with many seams, the high geostress features would have important influences to the exploration and development of coalbed methane. In order to discover the geostress affected to coalbed methane development, with the analysis on data of hydraulic fracturing well in the mining area, the paper had a discussion on the geostress affected to the reservoir pressure, permeability and over-pressure phenomenon. The study result showed that in Laochang Mining Area, the coal reservoir pressure mostly came from the geostress. The coalbed methane belonged to the pressure dominate stress gas. Meanwhile, the high geostress would have a high contribution to the fluid energy of the seam, would have an important role to keep the pressure status in the deep seam and would also cause big difficulty to the reconstruction of the coal reservoir. The pressure coefficient of each seam and the geostress gradient would have the fluctuation variation on the strata and the partial seam would be overpressure generally. With the min main stress increased, the permeability of the seam would be steadily reduced and the pressure coefficient would be steadily increased. The min main stress gradient of each seam also would have the fluctuation and could show a big difference between the geostress features of each seam. The fluctuation of the stress gradient would have the same to the fluctuation of the pressure coefficient and could approve that he geostress was the one of the main control factors to form the multi layers overlay and independent gas content system.