克拉玛依油田非均质砾岩油藏特征及其剩余油分布

Characteristics and remaining oil distribution of heterogeneous conglomerate reservoir in Karamay Oilfield

针对七中、东区复模态结构砾岩油藏精细描述及调整挖潜工作,分析了非均质砾岩油藏特征及其剩余油分布特点。利用剩余可采储量平面分布及产吸剖面分层动用状况特征,结合砾岩储层多类型孔隙群的非均质渗流系统,研究了剩余油分布规律、富集类型及挖潜方向,阐明了剩余油分布主要受多类型孔隙群、断裂及构造控制,以及受注采不完善、层间干扰、水驱损失及井况损坏等影响。平面上,剩余油集中分布在井间未动用部位、断裂附近、构造高部位及曾经动用但水淹程度不高且有效厚度较大部位;纵向上,剩余可采储量主要集中在克下组S73-3、S74-1砂砾体发育较好的小层上。从而提出了该区下一步实施稳油控水的治理措施,为提高该区开发后期整体油藏开发效果提供了新的思路和依据。

Aimed at the accurate reservoir description and potential tapping in the conglomerate reservoir with complex mode pore structure in No.7 Middle District and East District, this paper analyzed the features of heterogeneous conglomerate reservoir and remaining oil distribution. Taking advantage of the characteristics of plane distribution of remaining recoverable reserves and the separate layer producing of the production-entry profile, and based on the heterogeneous seepage system of multiple type porosity groups for the conglomerate reservoir, the remaining oil distribution law, the enriched type and potential tapping are researched. It is considered that the remaining oil distribution is mainly controlled by multiple type porosity groups, the fracture and the high part of structure. It is also affected by the imperfect injection-production, the interference at interlayer and the loss of water driving well condition. In plane, the remaining oil is mainly distributed in the nonproducing part of interwell, high part of structure, around the fracture and the part of exploited but low level waterflooding and major effective thickness. Vertically, the remaining recoverable reserves mainly enriched in Kexia Formation S7^3-3, S7^4-1, in which the sand body is well developed. Thereby, this paper proposed the next step measures for steadying oil production and controlling water in this area, which provides the new idea and basis for improving the whole reservoir development effect at the later stage in this oilfield.