针对鄂西地区二叠系含有机质页岩地层研究较少的实际,对该区二叠系大隆组地层特征进行研究.首先对大隆组分布面积、厚度展布及地层特征进行了详细描述,并采集露头样品进行了地球化学、储层物性及含气量测试分析,最后对大隆组页岩气资源潜力进行了评价.研究表明:大隆组分布面积较小,厚度稳定,以黑色炭质及炭硅质岩为主,主要沉积于水体较深的浅海外陆棚相沉积环境;大隆组TOC平均值为6.03%,Ro平均值为2.29%,达到过成熟阶段,有机质类型为腐泥腐殖型和腐殖型;大隆组主要矿物为石英和黏土矿物,脆性矿物含量高;岩石孔隙度为1.45%~4.26%,属于低—特低孔储层;渗透率为0.00017×10-3~0.00385×10-3μm2,属于特低渗储层.样品等温吸附测试含气量平均值为3.76 m3/t,页岩气潜在资源量为1654.8× 108m3.大隆组含页岩气地层研究可为鄂西二叠系页岩气的后续勘探开发提供依据.%The Permian Dalong Formation in the western Hubei Province is studied to further understanding the Permian organic-rich shale gas formation. Firstly,the distribution area,thickness distribution and stratum charac-teristics of Dalong Formation are described in detail. The geochemistry,reservoir property and gas content tests are implemented for the collected outcrop core samples. Finally,the shale gas resource potential is evaluated for Dalong Formation. Research indicates that the Dalong Formation with small distribution area and stable formation thickness mainly consists of black carbonaceous and carbonaceous-siliceous rocks,which dominantly deposited in the shallow outer continental shelf with relatively deep water. The average TOC of Dalong Formation is 6.03%,the average Ro is 2.29% to reach overmature stage and the organic matter includes sapro-humic and humic types. Quartz and clay are the major minerals in Dalong Formation with higher content of brittle content. The rock porosity is 1.45%~4.26%,which is considered as a low-porosity to ultra-low porosity reservoir. The permeability is 0.000 17×10-3~0.003 85×10-3μm2,which is classified as a ultra-low permeability reservoir. The average gas content of core samples is 3.76 m3/t according to the isothermal adsorption test and the corresponding shale gas potential resource is 1 654.8×108m3. The research on shale gas reservoir in Dalong Formation could provide certain reference for the subsequent Permian shale gas exploration and development in western Hubei Province.
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