注水开发后期下二门油田储层特征

二门油田经过近20年的注水开发，目前已进入高含水后期开采，由于该油田储层矿物及胶结物组分成熟度低，不稳定矿物和易溶解胶结物含量高，因此注入水的长期冲刷对储层物性及其它渗流特征参数影响较大，主要表现在：开发后期储层类型增多；孔隙和喉道的分布及组合配置关系更加多样化；大孔（喉）道与小孔（喉）道出现的频率和变化幅度在微观上表现出极大的差异性；相对渗透率参数变化范围加大且曲线类型更加复杂；油层润湿性、驱油效率及剩余油分布特征也发生相应的变化，使得储层非均质性更为严重，开采难度加大，常规“控水稳油””措施受阻。成果采用对比井分析、室内岩心物模实验、测井解释、动态分析、电子探针、敏感性评价等技术对注水开发后期储层特征进行详细探讨，其研究思路、方法和技术可在中国东部砂砾岩油藏储层评价中推广使用。

THE CHANGES OF OIL RESERVOIR FORMATION ROCK PROPERTIES IN HIGH WATER CUT PRODUCTION STAGE ON XIA-ERMEN OIL FIELD

Xia Ermen oil field entered the high water cut production stage after 20 year water flooding development.The petrophysical and microscopic parameters of the formation rock were largely changed by the long term water flushing because of the low maturity of the rock.There are many features:reservoir formation types increased, distribution and coordination number of pore and throat of porous rock were diversified dramatically,relative permeability curve were largely changed,wettability displacing efficiency and residual oil distribution of the formation were varied greatly.All of above mentioned changes made the formation more heterogeneous.The technique presented in the paper consist of several methods,such as couple coring well(100 meter well distance) analysis,core physical modeling test,comprehensive log interpretation,dynamic analysis,electronic probe and sensitivity evaluation. The developed methodology can be extensively applied to other high water cut oil field in East China.