Study On The Flow Units Of Gaoji Oil Field

Exploration and development time shows that the continental reservoirs in the east of our country have strong heterogeneity, reserves2/3of the total. The plane connectivity of the sand reservoirs is poor and there are numerous vertical oil layers with the serious heterogeneity of the reservoirs. After the long-term water-flooding exploitation, some oil field has entered the stage of high water-cut, which induced lower oil yield. The study of reservoir flow unit developed from the last century, which is the reservoir geological research theory and characterization method of the solution to reveal the underground reservoir remaining oil forming mechanism and distribution law of the oil field.In1996, Gaoji oil field was brought into production test, after the stages of rolling development, stable yield, adjustment and improvement which gained quite good effect. With deep development going, the oilfield is entering into the high water cut stage and facing a serious development situation.Aim at the problems as rapid increase in water cut and yield decline, this paper was carried out on the sand bodiesdepiction, seepage barrier, distribution pattern of flow unit, utilization of the flow unit, refined and deepen the geological understanding of the reservoir in the Gaoji oil-field base on a preliminary geological study. Moreover, provided methods to predict the remaining oil distribution and a development program, through these measures we provide the geological foundation for the Gaoji oilfield to achieve high and stable yield.In the first place, we did core observation and log data analysis based on which we started the work of single sand bodiesdepict and conclude the vertical and plane characterization. By these measures we fitting width-to-thickness ratio of the single sand bodiesand the described the tridimensional connection relationship of sand body, based on which we completed the description of the single sand body.In the second place, we established the standard of flow unit division and divided the flow unit into4types by chose parameters of porosity, permeability, FZI based on the description of the single sand body, after that we analyze the characterization and the factor of the flow unit.In the third place, through petrel we built the structure model of the reservoir and establish the face models, based on which we built up model of flow units by sequential indicator simulation algorithm. As a result, we got the regularities of distribution.In the last step, we predicted the potential area of remaining oil by research the relationship between the flow units and the remaining oil and systematic study on conditionality of types of remaining oil by flow units. Finally, we established the distribution pattern of the remaining oil restricted by each type of flow units.Through such the study, a suit of method how the flow unit of delta facies reservoir classify, correlate, evaluate, forecast has been created.This paper has researched flow unit classify method, flow unit forecast in space and application of flow unit. These conclusions has its value of application in the study of other continental reservoirs.