断层密集区块注水井注入压力界限研究

STUDY ON THE THRESHOLD OF INJECTION PRESSURE IN FAULT-DENSE ZONE

由于南二区西部构造复杂,断层密集分布,地层倾角大,2009年以来,发生了大面积油水井套管损坏。针对套损高峰持续时间较长,套损井数多,套损原因复杂等问题,基于数理统计规律分析,研究断层区、非断层区注入压力变化对套损影响。并研究不同地层倾角区域,注入压力变化对套损的影响、注聚压力升幅对套损的影响,在此基础上确定不同地质区域注入压力界限,依据界限优化区块注入调整方案,有效控制套损速度。

Since 2009,many casings of water and oil wells were damaged in the east of nan’er Development Area,because of complex geological structure and closely spaced faults and high dip angle.In consideration of many problems such as long period of maximum severity casing damage and a large number of casing damage wells and complex causes of casing damage,etc,based on the mathematical statistics and analysis of regularity,in fault area and non-fault area the injection pressure inducing casing damage were studied.Meanwhile,in diversified dip angle area the injection pressure inducing casing damage were studied,and pressure rise of polymer injection inducing casing damage was studied.On the basis of the above achievements,the threshold of injection pressure were defined in diversified geological structure realm.Based on the threshold,the block adjustment project of injection wells was optimized.This helps the rate of casing damage is controlled effectually.