Study On Remaining Oil Distribution Laws And Developmental Indices Prediction In North-II-East Tract After Layer-recombination

The target work area in this paper locates in the southeast of Sabei oil field pure oil zone.This tract is multiple zone and heterogeneity oilfield. Currently, the block is in the highwater-cut stage and its comprehensive water cut rate is93.72%. Layer and well patternmodification field test has launched in Oct.2010. The test used to relief conflicts betweenlayers, complicated injection-production relationship and staggered mining strata of wellpattern. Large span of development layer series, long well section and fuzziness series ofstrata division lead to the conflicts.The paper analyses the influence of layer adjustment in north-II-east tract, accordingwith analysis the actual production of dynamic and static data of north-II-east tract as well ascompares with the indicators of exploit before and after layer adjustment. The indicatorsinclude the perfect degree of the pattern, liquid-production capacity, oil production, watercontent, declining rate, net injection percent, oil recovery rate, productivity index and so on.It shows that development efficiency of reserves is improved and the water content iscontroled well after layer-recombination. In this paper we use numerical simulationtechnology to analyse and study remaining oil distribution based on history matching andgeological characteristics of target tract. The paper’s study shows that recovery percent ofreserves improve in each layer, especially in Saertu layer. Oil layer placement conditionbecomes better on the vertical after layer-recombination. Remaining potential mainlydistributes in Saertu layer. Imperfect injection-production type of remaining oil, the originalwell pattern retention area and heterogeneity of remaining oil has been developed afterlayer-recombination.It forecasts alteration development indicators before and after layer-recombination bynumerical modeling. The result shows that years of stable production is two. Optimizationstudy of dynamic adjusting technology after layer-recombination has been launched forfurther control water content and keeping rate maintenance capability. According to the wellpattern characteristics of layer series of development after layer-recombination, combinedwith the geological characteristics, it respectively studys optimum water intake per unitthickness and subdivided flood dividing line of four well patterns. Based on dynamic andstatic characteristics, we establish adjustment scheme of matching measures and conductdynamic production prediction. The adjustment schemes include fracture, profile control andwater shutoff and so on which are carried out in different waterflooding timeing (the water content is93%,95%and97%) of each development well pattern. The prediction results showthat all adjustment schemes of matching measures have some effect.Therefore, it is beneficialto control water cut raising, steady production oil amount and enhance oil recovery thatadjust development parameter and conduct adjustment schemes.