Revealing the distribution of coal-measure gas (CMG) in horizontal and vertical directions as well as the stimulation effect of coal-measure reservoirs under different geological conditions is significant for guiding the co-prospecting and co-production of CMG. In this study, the characteristics of in situ stress in the Daning–Jixian area were analyzed using optimized evaluation methods. Then, the effects of various stress parameters on the reservoir parameters, stimulation effect of coal seams, and spatial distribution of CMG were discussed. It was found that the pressure, gas content, and porosity of coal reservoirs show different trends with increasing vertical stress, namely linear increase, first increase and then decrease, and exponential decrease. Compared with transitional stress areas, fractures in tensile stress areas are likely to expand horizontally, and areas with tension stress states or larger horizontal stress differences have better stimulation effect. In addition, the gas content of coal reservoirs in horizontal directions is higher when the roof and floor (RF) are mudstones and the in situ stress index is lower. In comparison, the CMG is more likely to escape from hydrocarbon source rocks and enriches in the adjacent coal-measure reservoirs, when the RF are sandstones or the in situ stress index is higher. The lithology of RF is the crucial geological factor for gas content in the transition stress areas, whereas in situ stress is the most important geological factor in compression stress areas.

揭示煤系气水平和垂直方向的分布规律以及不同地质条件下煤系储层的增产效果，对于指导煤系气的联探联产具有重要意义。本研究采用优化评价方法对大宁—蓟县地区地应力特征进行了分析。然后讨论了各种应力参数对储层参数、煤层改造效果以及煤层气空间分布的影响。研究发现，随着垂向应力的增加，煤储层的压力、瓦斯含量和孔隙度呈现出不同的变化趋势，即线性增加、先增加后减少和指数减少。与过渡应力区相比，拉应力区裂缝更容易水平扩展，拉应力状态或水平应力差较大的区域改造效果更好。此外，当顶底板（RF）为泥岩时，煤储层水平方向瓦斯含量较高，地应力指数较低。相比之下，当RF为砂岩或地应力指数较高时，CMG更容易从烃源岩中逃逸并在邻近煤系储层中富集。 RF岩性是过渡应力区含气量的关键地质因素，而地应力是压应力区最重要的地质因素。