高邮凹陷高含水砂岩油藏储层物性变化特征及影响因素分析

Analysis of reservoir physical properties and influencing factors of high water cut sandstone reservoir in Gaoyou sag

高含水砂岩油藏经过长期注水后,其物性会发生变化,对油藏开发产生明显的影响。为此,通过利用不同渗透率的岩心开展了水冲刷实验研究,并在实验基础上分析了黏土矿物、孔喉特征及岩石润湿性等对储层物性变化的影响。实验结果表明,渗透率较大的样品随着注水倍数的增加,渗透率逐渐增大;渗透率较小的样品随着注入倍数的增加,渗透率逐渐减小;且不同注入速度会影响物性的最后变化程度;黏土矿物含量、孔喉特征和岩石润湿性三者对储层物性变化有影响,其中黏土矿物含量对物性变化影响最大,孔喉特征和岩石润湿性影响较小。

After long-term water injection,the physical properties of high water cut sandstone reservoirs will change,which will have an obvious impact on reservoir development.Therefore,by using different cores with different permeability,water erosion experiments were carried out.Based on the experiment results,the effects of clay minerals,pore throat characteristics and rock wettability on reservoir physical properties were analyzed.The experimental results show that the permeability of the sample with high permeability increases with the increased number of injection multiple,and the permeability of the sample with low permeability decreases with the increased number of injection multiple.And different injection rate will affect the final change degree of physical properties.Clay mineral content,pore throat characteristics and rock wettability have influences on reservoir physical properties,among which clay mineral content has the greatest influence on physical properties,while pore throat characteristics and rock wettability have less influence.