川南地区深层页岩气储层特征及含气性主控因素  

Reservoir characteristics and main controlling factors of gas content of deep shale gas in Southern Sichuan Basin

作　　者：向克满 史洪亮[1] 王幸蒙 赵勇[2] 董晓霞[2] 庞河清[2] 张烨毓 XIANG Keman;SHI Hongliang;WANG Xingmeng;ZHAO Yong;DONG Xiaoxia;PANG Heqing;ZHANG Yeyu(Department of Unconventional Oil and Gas Exploration and Development Management,Southwest Oil&Gas Branch of SINOPEC,Chongqing 402160,China;Exploration and Development Research Institute,Southwest Oil&Gas Branch of SINOPEC,Chengdu,Sichuan 610041,China;Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province,Chengdu,Sichuan 610091,China)

机构地区：[1]中国石化西南油气分公司非常规油气勘探开发管理部,重庆402160 [2]中国石化西南油气分公司勘探开发研究院,四川成都610041 [3]页岩气评价与开采四川省重点实验室,四川成都610091

出　　处：《东北石油大学学报》2023年第3期44-55,I0004,I0005,共14页Journal of Northeast Petroleum University

基　　金：中国石化科技重大专项(P21042-1)。

摘　　要：深层页岩气是非常规天然气勘探的重要目标。以川南威荣页岩气田五峰—龙马溪组为研究对象,利用地球化学测试、X线衍射矿物分析、场发射扫描电镜、气体吸附实验及含气性测试等方法,分析深层页岩气储层特征及含气性,探讨含气性主控因素。结果表明:深层页岩气储层具有高TOC、高孔隙度、高含气量和高脆性矿物质量分数的特征;深层五峰—龙马溪组页岩主要孔隙类型为迁移有机质孔,存在黏土矿物层间孔,中孔和微孔约占孔体积的88%。纵向含气量具有差异性,呈底部含气量高、顶部含气量低的特征,页岩含气性受多种地质因素控制,TOC质量分数是控制含气性主要因素之一,与含气性呈正相关关系;低矿物质量分数对含气量有利,石英对含气量具有积极作用,黏土和碳酸盐矿物对含气量具有双重作用;岩相对含气量影响明显,富碳硅质页岩含气量最好,为优质岩相类型;高角度裂缝对含气量不利,水平裂缝发育区含气量较高;地层压力越大,页岩含气量越高。该结果对深层页岩气勘探开发具有指导意义。Deep shale gas has become an important target of unconventional natural gas exploration and development.Taking the Wufeng-Longmaxi Formation of Weirong shale gas field in Southern Sichuan Basin as the main research object,geochemical test,X-ray diffraction,field emission scanning electron microscope,thin section,gas adsorption experiment and gas content test were used to analyze the characteristics and gas content of deep shale gas reservoir,and to discuss the main controlling factors of gas content.The results show that the deep shale reservoir is characterized by high rate of TOC,porosity,gas content and brittle mineral content.Migrated organic matter pores are the main reservoir space for shale gas in Wufeng-Longmaxi Formation,followed by interparticle pores of clay minerals.Mesopores and micropores contributes most of the pore volume,which account for about 88%of the total pore volume.The gas content of shale is controlled by various geological factors,and the total organic matter content is the main controlling factor of the gas content,which is positively correlated with the gas content.Different minerals have different effects on gas content.Quartz has positive effects on gas content,clay and carbonate minerals have double effects on gas content.When mineral content is low,it is positive to gas content,while pyrite content has no obvious effect on gas content.The gas content of shale is controlled obviously by lithofacies,and the carbon-rich siliceous shale is the best type of high-quality lithofacies.Different fracture types have different effects on gas content.High angle fractures have negative effects on gas content,while areas with horizontal fractures developed have higher gas content.In addition,gas content is also affected by formation pressure,and the higher formation pressure,the higher gas content.This result has important guiding significance for deep shale gas exploration and development.

关 键 词：储层特征 含气性 主控因素 深层页岩气 五峰—龙马溪组 四川盆地 

分 类 号：TE122[石油与天然气工程—油气勘探]