基于8口钻井、2个剖面点的岩样观察和测试分析，滇黔北坳陷及邻区下志留统龙马溪组下段是富有机质泥页岩发育的层段，有机质演化达到过成熟阶段。 X衍射全岩分析表明，龙马溪组泥页岩由黏土矿物、石英、碳酸盐、长石、黄铁矿等矿物组成，黏土矿物则以伊利石为主。泥页岩的平均脆性指数56.11,~73.21,，压裂时易于形成网络裂缝；常规物性测试，孔隙度、渗透率很低，扫描电镜观察，纳米级孔隙和裂缝发育。

Based on observation and test analysis of the gas-bearing shale samples from eight drilled wells and two out-crops, it is shown that the Lower Silurian lower Longmaxi shale reservoir is organic-rich and over-mature in Dianqianbei Depression and its adjacent area. The analysis of X-ray diffraction indicates that the Longmaxi shale is composed of clay minerals, quartz, calcite, feldspar, dolomite, pyrite etc., and illite is predominant in clay minerals. The average brittleness index of the shale is distributed from 56.11, to 73.21,, which makes it easy to form the network fractures.The test of conventional physical properties shows that porosity and permeability are low in the shale, but the observation by ESEM shows that nanometer-scaled pores and fissures develop.