Based on the geological data and drainage dynamic data in two blocks,this paper analyzes the causes of difference between the two blocks from three aspects including resources,fluid mobility and fracturing engineering conditions,discusses the key issues of CBM development of Shouyang block and gives some suggestions.The study shows that the resources and the fluid mobility of each coal seam in Shizhuang are wonderful,so Shizhuang block is suitable for CBM development.The resources of each coal seam in Shouyang block are weak but the ultimate recovery resources of multiple coal seams is up to 1.57× 10s m3/km2 and the desorption potential is also satisfactory since desorption quantity index of each single seam is about 9 m3/t.What's more,the fluid mobility is beneficial to CBM development,the average value of permeability is 7.57× 10-3 μtm2,even though the adsorption time is more than 15 d.Compared with Shizhuang block,there are not only more sandstone aquifers with high permeability in coal measure strata in Shouyang block,but also the actual implementation of fracturing is bigger,so the fault and hydraulic fractures are easy to connect coal seam with aquifers.It is suggested that multiple coal seams developed together is a necessary way for Shouyang block.When it comes to select appropriate well horizon,it is crucial to avoid faults,take into account the lithological combination of coal roof and floor and optimize or control fracturing volume.%基于沁水盆地寿阳和柿庄区块的地质和排采资料,从主采煤储层的资源性、储层流体可动性、压裂工程条件开展2个区块的对比分析,讨论寿阳区块煤层气开发的关键问题,提出下一步开发对策.结果表明:柿庄区块各煤层的资源性和流体可动性较好,具备单层排采的条件,而寿阳区块主力煤层的累计资源丰度高达1.57×108 m3/km2,解吸潜力大,3套煤层的有效解吸量均为9 m3/t左右,流体可动性强,渗透率平均7.57×10-3 μrm2,吸附时间大于15d,具备多层合采的条件;与柿庄区块相比,寿阳区块煤系中砂体发育广泛,煤系外源水供给能力更强,且实际压裂规模更大,断裂和压裂缝沟通含水层造成煤层气井高产水的风险更大.建议寿阳区块坚持以合层排采为主,在井层优选时,首先应规避断裂,其次应考虑目标煤层顶底板的岩性组合,同时要注意优化和控制压裂规模.
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