关键词: 高含水期,    ,  注采系统,    , 井网调整,    ,  井距界限,    , 开发矛盾

Abstract: In the early stage of the Gaotaizi reservoir in the middle of of Sazhong development zone, the 300 m inverted nine spot area of the injection water well pattern was developed. During the middle and late stages of reservoir development, many problems were exposed in the process of development such as the complex injectionproduction relationship, too large well spacing, inadequate production of reserves and serious enrichment of remaining oil. Therefore, it is necessary to carry out the optimization of injection and production well pattern. Combined with the actual production data of Gaotaizi reservoir, three kinds of water injection wells, which are common in Daqing oilfield, are studied based on injection and production intensity, oil recovery rate and water flooding control degree. From the two aspects of engineering methods and economy aspects, the technical and economic limit wells of different well patterns in the study area are discussed. On this basis, four kinds of calculation methods are proposed to determine the reasonable well spacing of high water cut stage of oilfield development.This paper provides a complete set of methods to determine the reasonable well pattern and well spacing, which can be applied to other oil fields with similar geological conditions. The research findings have important guiding significance and application value for the injectionproduction system adjustment of the oilfields in medium and high water cut stage.

Key words: High water cut stage,    ,  Productioninjection system,    ,  Well pattern adjustment,    , Limit of well spacing,    , Development contradiction