Study On Remaining Oil Description In Complex Heterogeneous Reservoir At Super-high Water Cut Period Of Gudao Oil Field

Based on the theory of contemporary river deposition,this paper aims at heterogeneous reservoir of Gudao oil field at super-high water cut period. With development geology and modern reservoir engineering methods and from analysis of reservoir hierarchies process and fine geological studies of river facies reservoir, sedimentary barriers and sand causeare analyzed, and fine reservoir building structural framework model is established. Also, by studying the remaining oil distribution at well points and in well layers and interwell areas, 3D distribution of the remaining oil is ultimately revealed. Moreover, at super-high water cut period,the predominant factors impacting the remaining oil distribution at Gudao oil field are demonstrated to be reservoir heterogeneity and non-homogeneous producing. During this period, the remaining oil distributes at such places: Thin and poor layers at lower producing Capacity, interfluve caused small-scale and isolated reservoir sand or origin sandbodies segmental parts with low waterflood swept efficiency, inner local area of positive rhythm thick layers with interlayers, neighborhood of oil well lines with low water cut and between oil or water well lines or near separate streamlines etc. According to the above, reservoir development adjustment measures are proposed and performed to increase water drive recovery efficiency and good results from oil field producing countermeasure have been achieved. In addition, a new method, whose content is the study of reservoir building structural framework, is formed to describe remaining oil at high water cut period. Therefore, "secondary oil prospecting" theory and technology is enriched and improved.