渝东南地区五峰组--龙马溪组页岩气成藏地质条件与有利区预测  

Geological Condition of Shale Gas Accumulation and Favorable Area Prediction for the Wufeng——Longmaxi Formations in Southeastern Chongqing

作　　者：谭淋耘 徐铫[1] 李大华[1] 程礼军 曾春林 

机构地区：[1]国土资源部页岩气资源勘查重点实验室、重庆地质矿产研究院,重庆400042 [2]重庆市地质灾害防治中心,重庆400015 [3]重庆市页岩气资源与勘查工程技术研究中心、重庆地质矿产研究院,重庆400042 [4]油气资源与探测国家重点实验室重庆页岩气研究中心,重庆400042

出　　处：《地质学报》2015年第7期1308-1317,共10页Acta Geologica Sinica

基　　金：国家“973”计划“渝东南地区页岩气资源潜力评价”(编号2012CB214705-05);“重庆市页岩气成藏富集规律”(编号CIGMR1104);“渝东南地区下古生界泥页岩聚集分布规律及成岩系统研究”联合资助成果

摘　　要：上奥陶统五峰组—下志留统龙马溪组是四川盆地页岩气勘探的重要层位。通过地层厚度、地层埋深、总有机碳含量、有机质类型、有机质成熟度及储层含气量等参数的综合分析,表明渝东南地区五峰组—龙马溪组具有泥页岩厚度大（40～210m）、地层埋深较浅（〈4500m）、总有机碳含量较高（TOC一般〉1.5%）、有机质成熟度高（Ro为1.9%～2.7%）等特点,有机质类型多以Ⅰ型为主,现场解吸含气量在五峰组及龙马溪组中下部具有较好的水平。综合分析认为,五峰组—龙马溪组具有较好的页岩气成藏地质潜力。运用多因素叠加及综合地质分析技术,选取总有机碳含量、热成熟度、地层埋深、地层厚度、地表条件5个参数作为核心评价指标对渝东南地区五峰组—龙马溪组的成藏有利区进行了预测,共预测出Ⅰ类有利区6个,Ⅱ类有利区2个,有利区预测结果与目前已有钻井的含气量水平相一致。最后,提出了＂有重点、有先后、分层次＂的勘探开发部署建议。Wufeng—Longmaxi Formations are an important sequence in Sichuan Basin for shale gas exploration.Comprehensive analyses of the geological parameters of stratigraphic thickness,buried depth,total organic carbon content,types of organic matter,organic matter maturation and gas content,indicate that there are big shale thickness（40～210 m）,shallow buried depth（〈4500 m）,high total organic carbon content（TOC〉 1.5%）and high organic matter maturity（Ro=1.9% ～2.7%）in Wufeng—Longmaxi Formations.Moreover,the type of organic matter is mainly type I and the field desorption gas content in the lower and middle parts of Wufeng—Longmaxi Formations have a good level.In a word,Wufeng—Longmaxi Formations have good potential for shale gas accumulation.Using multi-factor superposition and comprehensive geological analysis method,this study selected five parameters,such as total organic carbon,thermal maturity,the buried depth,stratigraphic thickness and the surface condition as the core evaluation index,to predicting the favorable accumulation areas.Six class I and two class II favorable areas have been defined in the Wufeng—Longmaxi Formations.The prediction results accord with the existing drilling gas content.Finally,this paper puts forward an exploration and development strategy of ＂focus,priority and hierarchical＂.

关 键 词：渝东南 页岩气 成藏地质条件 五峰组 龙马溪组 

分 类 号：P618.13[天文地球—矿床学]