核磁共振测井连续表征储层孔隙结构方法研究

核磁共振测井资料评价储层孔隙结构的方法已有了突破性的改进,但诸多方法中均存在储层含烃的影响,储层含烃使计算的孔隙结构参数误差偏大。通过含烃储层中伪毛细管压力曲线计算孔隙结构参数的误差与含油饱和度曲线对比发现,用含油饱和度能有效消除储层含烃的影响。并用横向弛豫时间T2几何均值拟合法与消除储层含烃影响后的伪毛细管压力曲线转换法进行对比,两种方法有很好的一致性,都能高精度地、连续地表征储层孔隙结构,可用于实际生产。

A Research of Successively Characterizing Reservoir Pore Structures with NMR Logging Data

The evaluation on reservoir pore structure was improved by using nuclear magnetic resonance(NMR) logging data,but there were many methods influenced by hydrocarbon in reservoirs which caused bigger errors for calculating the pore structure parameters.By comparing pseudo-capillary pressure curve calculation error of the pore structure parameters with oil saturation curve in the hydrocarbon reservoirs,it is found that oil saturation can effectively eliminate the influence of the hydrocarbon reservoirs.And the fitting method of geometric mean of transverse relaxation time T2 is compared with pseudo-capillary pressure curve transformation method that the influence of hydrocarbon reservoir is eliminated,the two methods have good consistency.Both methods can be used to successively characterize the pore structure of reservoirs with high precision,therefore they can be used for practical production.