疏松砂岩储层成岩相划分与定量表征--以准噶尔盆地东部三台油田北10井区为例

Division and quantitative characterization of diagenetic facies of unconsolidated sandstone reservoir:a case study of Bei 10 well area,Santai Oilfield,eastern Junggar Basin

准噶尔盆地三台油田北10井区侏罗系储层发育大面积连片疏松砂岩,生产开发过程中存在出砂、携砂等问题。为研究储层出砂机理,需划分并表征疏松砂岩储层成岩相。观察岩心及铸体薄片,结合野外露头等资料,根据储层岩相形成机制及主控因素,将研究区疏松砂岩储层岩相划分为自生黏土矿物充填相、弱胶结不稳定组分溶蚀相、颗粒支撑砂砾岩相。利用常规测井数据,将变化范围较广、灵敏度较高的测井响应组合进行交会,以投点效果较好的密度-自然伽马交会组合建立定量决策模型,可为疏松砂岩储层成岩机制研究提供指导。

The Jurassic reservoir in Bei 10 well area of Santai Oilfield in Junggar Basin is developed with large area of unconsolidated sandstone,and there is a problem of sand production and carrying in the process of production and development.In order to study the mechanism of sand production,the diagenetic facies of unconsolidated sandstone reservoir should be classified and characterized.Based on the core,cast thin sections,and field outcrop data,according to the formation mechanism and main control factors of reservoir lithofacies,the lithofacies of unconsolidated sandstone reservoir in the study area can be divided into autogenetic clay mineral filling facies,weak cementation instable components dissolution facies and particle supported glutenite facies.By using conventional logging data,the logging response combination with wide variation range and high sensitivity is intersected.The quantitative decision-making model is established by the intersection of density and natural gamma with good effect of point throwing,which can provide guidance for the study of diagenetic mechanism of unconsolidated sandstone reservoir.