赣西北九瑞区块王音铺组页岩气成藏条件

Shale Gas Reservoir- forming Conditions in Wangyinpu Formation,Jiurui Block,Northwest Jiangxi

根据赣西北九瑞区块下寒武统王音铺组黑色页岩实测剖面、地表样品的测试等资料，对研究区下寒武统王音铺组页岩的分布与沉积特征、地球化学特征、储层特征和页岩气保存条件等进行分析。结果表明：赣西北九瑞区块下寒武统页岩分布较广泛，沉积厚度较大，可达50～150m，主要为深水陆棚相沉积；页岩的有机质丰度高，TOC含量高达2．0％以上，有机质类型主要为Ⅰ型，成熟度高，达到过高成熟度阶段；页岩中脆性矿物含量高，以石英为主，黏土矿物含量中等，主要为伊利石。等温吸附实验测试页岩的吸附气含量平均为3．21m3／t，采用信息叠合法，初选瑞昌-九江一带为该区页岩气有利勘探区，采用体积法计算该区页岩气总资源量为0．93×10^12～1．85×10^12m3，显示出研究区具有很好的页岩气资源潜力。

According to the measured profile of dark shale in Wangyinpu Formation,lower Cambrian,Jiurui Block,Northwest Jiangxi,as well as measurements of surface samples,distribution and sedimentary features,geochemical features,reservoir features and conservation conditions of shale gas in Wangyinzu Formation,lower Cambrian in the study area have been analyzed. Results show that the shale gas in lower Cambrian,Jiurui Block,Northwest Jiangxi,is extensively distributed,with large sedimentary thickness,up to 50- 150 m,mainly as deep continental shelf sediments; organic matter abundance of shale is high,TOC content is up to 2. 0%; organic matter types was type I with high maturity,reaching high mature stage; brittle content of minerals in shale is high,dominated by quartz; content of clay is medium,dominated by illite. Adsorption of shale gas based on isothermal adsorption test averaged at 3. 21 m3/ t. Information superposition method was adopted. Jiujiang- Ruichang was initially selected as favorable area for shale gas exploration. Volumetric estimate is used to calculate shale gas resources,amounting to 0. 93 × 1012- 1. 85 × 1012m3,showing that the study area had good potential of shale gas resources.