注水指示曲线在碳酸盐岩油藏的应用

Application of waterflood index curve in carbonate reservoirs

塔河油田奥陶系缝洞型碳酸盐岩油藏埋藏深,储集空间多样,油水关系复杂。缝洞型碳酸盐岩基质基本不具备储渗能力。裂缝和溶洞既是储集空间,也是主要的连通通道。注水指示曲线能很好地反映注水过程中油井压力随着累计注水量增加的变化情况,对初步分析储集体类型以及规模提供了可靠的依据。因此,注水指示曲线的应用,能基本反映储集体以及裂缝等油藏特征,显示储层吸水能力的变化,为初步分析储集体类型以及规模提供可靠依据,指导后期注水工作以及措施作业。

The Ordovician fractured-vuggy carbonate reservoirs in Tahe oilfield are deeply buried with multiple storage space and complex oil-water relation. The matrix of fractured-vuggy carbonate rocks have little storage and permeability capacity. Fracture and vug are not only the storage space, but also the main connected channels. Waterflood index curve can well reflect the change of the oil well pressure with the increase of the cumulative water injection rate during the waterflood process and provide a reliable basis for the preliminary analysis of the accumulative body types and scale. Therefore, the application of waterflood index curve can basically reflect the reservoir characteristics of the accumulative bodies and the fractures, show the change of the absorption capacity of the reservoirs, provide a reliable basis for the preliminary analysis of the accumulative body types and scale, and guide the waterflood operations and measures in the later period.