河流相储层剩余油成因类型及分布模式

Genetic type and distribution mode of the remaining oil in the fluvial reservoirs

以鄂尔多斯樊家川油田为例,通过综合分析开发地质、生产动态资料,研究了河流相储层剩余油成因类型及分布模式。河流相储层剩余油可细分为13种成因类型,其中井网未控制型、注采不完善型、层间干扰型、呈片分布差油层型、微正向构造控制型剩余油是注水开发后期主要挖潜的对象。在纵向上,剩余油分别呈分散相、片状、集合块状连续层状分布于单砂体不同部位,在渗透性差异较大的不同砂体之间由于层间干扰形成层间干扰型剩余油;在平面上,河道砂主体侧缘主要为决口扇或溢岸成因的薄层近未水淹剩余油层和上倾尖灭型剩余油。而在河流相复合砂体的任何部位,都可能存在被漏掉的微砂体、微构造型、外延断棱型剩余油。

This paper studies the genetic type and distribution mode of the remaining oil in the fluvial reservoirs in the Fanjiachuan oilfiled of Ordos Basin by comprehensively analyzing exploitation geology and dynamic information of production. The remaining oil in the fluvial reservoirs is subdivided to 13 genetic types, in which the type not controlled by well net, the type of faultiness in injection-production, the type caused by disturbance in bed, the type of bad reservoirs distribution in patch, and the type controlled by tiny positive direction structure are the objects of the main digging potentials. In the vertical, the remaining oil is distributed over different parts of the single sand body in the forms of separate, patch, aggregate block and layer form, and in the different penetrability sand bodies, there exists the remaining oil of the type caused by disturbance in bed. In the plane, there exist the thin layer and no-water floodding remaining oils caused by crevasse splay and overflow bank part of the fluvial facies complex sand body.