中东H油田低渗透碳酸盐岩油藏多层水驱核磁共振实验研究

摘要

针对中东地区H油田M组低渗透碳酸盐岩油藏非均质性特征,开展多层水驱油物理模拟实验,结合核磁共振弛豫时间T2谱技术,对不同渗透率组合的微观剩余油和采出程度分布状况进行研究.核磁共振测试对于不同孔隙结构类型具有不同的响应,渗透率越大,核磁共振弛豫时间T2谱越靠右、峰值越高,说明可动流体越多.渗透率级差对多层水驱残余油及采出程度具有一定的影响,不同渗透率组合岩样的残余油和采出程度的绝对值和相对值差异较大.渗透率级差越大,小孔隙中残余油相对值越少,采出程度相对值越大;残余油绝对值与采出程度绝对值主要分布在大孔隙中,小孔隙很少.同一渗透率级差中低渗透率岩样的残余油大于高渗透率岩样,大孔隙的开发潜力仍很大.%Aiming the heterogeneity of low permeability carbonate reservoir in M group of H oilfield,carried out the physical simulation experiment of multi-layer waterflooding,and based on the T2 relaxation spectrum technique,studied the micro distribution of residual oil and production degree of different permeability combination.Results show that to the different pore structure types,NMR tests have different responses.The permeability is larger,the T2 relaxation spectrum is more,the peak value is higher,and the movable fluid is more.The difference of permeable grade has certain influence on the residual oil and recovery degree of multi-layer waterflooding,and the residual oil and recovery degree of rock samples with different permeability are different in absolute value and relative value.The absolute value of the absolute value and recovery degree of the residual oil are mainly distributed in the large pores,and the low porosity is very small,the smaller the relative value of the residual oil in the small pores,the larger the relative value of the recovery degree.The residual permeability of rock samples with the same permeability difference is higher than high permeability rock samples,and the exploitation potential of macro-pores is still large.