准噶尔盆地深层-超深层碎屑岩致密气储层特征及其控制因素

Characteristics and controlling factors of deep to ultra-deep tight-gas clastic reservoirs in the Junggar Basin

孙靖 尤新才 薛晶晶 郑孟林 常秋生 王韬

Jing SUN Xincai YOU Jingjing XUE Menglin ZHENG Qiusheng CHANG Tao WANG

为寻找准噶尔盆地深层-超深层有利碎屑岩致密气储层，利用钻井、录井、薄片及化验资料，研究了碎屑岩致密气储层发育特征、储集空间类型、物性变化特征及有利储层控制因素。研究结果表明：①深层-超深层有利碎屑岩致密气储层储集岩主要为三角洲砾岩和砂岩，以细砾（砂）岩、中砾（砂）岩及中-细砾（砂）岩为主，为岩屑类砂岩。砾石成分和砂岩岩屑以凝灰岩为主，胶结物主要为方解石，局部富集沸石类。②储集空间为孔隙和裂缝，以孔隙为主。储集空间有孔隙型、裂缝型和孔隙-裂缝混合型3种组合类型。孔隙主要为原生剩余孔隙和次生溶蚀孔隙，以次生溶蚀孔隙为主。裂缝以成岩压实微裂缝和构造裂缝为主。③碎屑岩致密气储层垂向上形成了3个次生孔隙发育带。④岩石成分、建设型成岩作用和异常高压是控制有利储层的主要因素，3个主要因素控制了盆地深层-超深层碎屑岩致密气有利储层的发育和分布。

To explore favorable deep to ultra-deep tight-gas clastic reservoirs in the Junggar Basin， we investigate the developmental characteristics， storage space types， changes in physical properties， and controlling factors of these reservoirs using data from drilling， logging， thin-section observation， and assays. Key findings are as follows： （1） Favorable deep to ultra-deep tight-gas clastic reservoir rocks in the basin are mainly of deltaic conglomerates and sandstones， which are dominated by fine-， medium-， and medium- to fine-grained conglomerates/sandstones and can be classified as lithic sandstones. Of these， gravels and sandstone detritus consist primarily of tuffs， and the cements are dominated by calcite， with locally enriched zeolite. （2） The storage spaces consist of pores and fractures， dominated by pores. Accordingly， the storage spaces can be categorized into three types： pore， fracture， and mixed pore-fracture types. The pores are mainly primary residual and secondary dissolution pores， with the latter being predominant， while the fractures are composed mainly of diagenetic compaction-induced micro-fractures and tectonic fractures， （3） forming three secondary pore zones vertically. （4） Major factors governing the favorable reservoirs include rock composition， constructive diagenesis， and anomalously high pressure， which jointly control the development and distribution of favorable deep to ultra-deep tight-gas clastic reservoirs in the Junggar Basin.

10.11743/ogg20240411