沁水盆地寿阳区块含煤地层主要是山西组和太原组，山西组3#煤层和太原组9#、15#煤层在全区分布较稳定，含气量高，适合进行煤层气开采。利用钻井、测井资料和煤层气排采动态资料，开展了煤系含水层的精细划分，认为影响煤层气排采的含水层主要有K1、K2′、K5、K7和K7′等5个砂岩层；太原组薄层灰岩因岩性致密，含水弱或不含水，对煤层气排采影响有限；K2下之上含水砂岩层可能是主要出水层。研究认为，该区煤层气井产水量受煤层与其上下岩性组合的控制，岩性组合类型平面分布特征对煤层气排采具有指导作用；区内15#煤层开发最有利，东北部该煤层排采可能较西南部好；3#煤层次之，南部地区较北部地区有利；9#煤层分布不稳定且上下均有较厚含水层，开发最为不利。%Coal-bearing strata are mainly Shanxi and Taiyuan formations in the Shouyang area, Qinshui Basin. The coal No.3 in Shanxi Formation and coal Nos.9, 15 in Taiyuan Formation are steadily distributed in whole area with high methane content, thus propitious to CBM exploitation. Through drilling, logging data and CBM drainage data carried out fine partitioning of aquifers in coal measures, con⁃sidered that CBM drainage impacting aquifers mainly have K1, K2′, K5, K7 and K7′five sandstone aquifers. Because of lithological com⁃pact, the thin limestone layers in Taiyuan Formation are weakly water containing or without water, impact on CBM drainage is limited;while water-bearing sandstone above K2L is main water-yielding stratum. The study considered that water yield of CBM wells in the ar⁃ea is controlled by coal seams and lithological associations above and below, the planar distribution features of lithological associations have guiding significance to CBM drainage. Coal No.15 in the area has most advantageous to CBM exploitation, it is better in the north⁃eastern part than in southwestern part;the coal No.3 is the second, southern part is better than northern part;coal No.9 is unsteadily dis⁃tributed and thicker aquifers above and below, thus most unfavorable to exploit.
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