摘要
基于煤层气井实测含气量测试、镜下观察、等温吸附实验等手段,对古交地区煤储层煤岩煤质、显微裂隙、渗透率、含气性等进行了分析。结合煤层气资源丰度平面分布特征,探讨了该区煤层气基础地质条件及其资源潜力。研究表明：古交地区煤层经深成变质和岩浆热源叠加变质作用演变为现今的中高煤级焦煤、廋煤和贫煤,煤储层显微裂隙较为发育,渗透率在（0.01~0.15）×10^-3μm2之间;储层压力梯度处于0.38~0.65 MPa/100 m,含气饱和度介于53.1%＆96.5%之间,属于欠压欠饱和煤层气藏;煤层周围致密的泥质岩层使得煤层气具有良好的保存条件,后期受东南部祁县隐伏侵入岩体以及西部狐偃山岩浆岩体的影响,二次生烃作用使得煤层含气量普遍较高,煤层平均含气量在9.8 m3/t;该区煤层气资源丰度分布在狮子沟#马兰向斜中南段和杜尔坪断裂带周围存在两个资源丰度富集区,具有较好的勘探开发前景。
Based on the gas content test,microscopic observation,experiment of isothermal adsorption etc methods,the coal rank,micro fracture,permeability,gas content were analyzed in Gujiao coalbed gas reservoir.Combined with the coalbed gas resource abundance plane distribution characteristics,the basic geological conditions and the resource potential of coalbed gas were discussed in this area. Research shows that,Gujiao area coal seam through plutonic metamorphism and magmatic heat source superimposed metamorphism evolved into today ＇s middle-high rank coal. The coal reservoir microscopic fissure and permeability is between 0. 01 × 10^- 3μm2to0. 15 × 10^- 3μm2. Reservoir pressure gradient is between in the 0. 38 MPa /100 m to 0. 65 MPa /100 m,and the gas saturation is between in 53. 1% to 96. 5%,belonging to the undervoltage and undersaturated coalbed gas reservoir. The surrounding dense argillaceous rock of coal seam makes coalbed gas has good preservation conditions. In the influence of the Southeast Qixian concealed intrusive igneous rock and Western Huyanshan magmatic rock,two secondary hydrocarbon generation of coal bed gas make the coal seam gas content is generally high,average gas content of coal seam in this area around 9. 8 m3/ t. According to the resource abundance distribution of coal bed gas,There are existing two gas rich center： south of Shizigou-Malan syncline and around the Duerping fault zone.The two areas have good prospects for exploration and development.
出处
《科学技术与工程》
北大核心
2015年第33期155-160,165,共7页
Science Technology and Engineering
基金
中海油能源发展重大专项(WBS:E-J313N020)资助
关键词
古交地区
渗透率
含气量
二次生烃
资源丰度
有利区
Gujiao Area permeability gas content secondary hydrocarbon generations resource abundance favorable area
