石油与天然气地质 ›› 2011, Vol. 32 ›› Issue (1): 124-132.doi: 10.11743/ogg20110115

• 石油与天然气地质 • 上一篇    下一篇

川东南地区须家河组低阻气层成因机制

  

  • 出版日期:2011-02-28 发布日期:2011-04-28

Genetic pattern of lowresistivity gas reservoirs in the Xujiahe Formation, southeastern Sichuan Province

  • Online:2011-02-28 Published:2011-04-28

摘要:

川东南地区上三叠统须家河组含气层普遍具有低阻特征,成因类型复杂多样,气、水关系复杂,识别难度大。利用岩心分析化验、录井、测井、构造及试油等资料,结合低阻气层测井响应特征,从宏观和微观方面入手,对该区低阻气层成因机制进行系统深入剖析。研究表明,造成该区低阻气层的主控因素为:①低幅度构造背景下发育低孔、低渗泥质砂岩储层;②孔隙结构复杂,高束缚水饱和度,高地层水矿化度;③低能沉积环境下储层颗粒细,泥质含量较高,粘土矿物附加导电性及局部导电矿物富集。储层物性与电阻率呈一定负相关关系。

关键词: 关键词:孔隙结构, 低幅构造, 成因机制, 低阻气层, 沉积环境, 须家河组, 川东南地区

Abstract:

Gas reservoirs in the Upper Triassic Xujiahe Formation, southwestern Sichuan Province are characterized by low resistivity, complex genetic types and complex gaswater relationships, which make them hard to identify. Using data from core analysis, logging, structures, testing and logging responses, we thoroughly examine genetic pattern of low resistivity gas reservoirs in the study area from macro and microviews. According to this study, main controlling factors responsible for the development of these low resistivity gas reservoirs are: 1) muddy sandstone reservoirs with low porosity and permeability developing in the context of lowamplitude structures; 2) complex pore configurations, high water saturation, and high formation water salinity; 3) lowenergy sedimentary environment resulting in fine particles in reservoirs, high mud content, some clay minerals with conductivity and enrichment of conductive minerals in certain areas. Reservoir quality has a negative correlation with resistivity.