基于孔渗关系的渗透率粗化方法分析

用测井解释孔隙度、基于岩心分析的孔渗模型可以得到渗透率; 粗化渗透率可按厚度加权算术平均或按厚度加权几何平均。研究证明, 用厚度加权算术平均孔隙度基于孔渗模型计算得到的渗透率, 等于渗透率直接按厚度加权粗化的几何平均值, 并不是按厚度加权的算术平均值; 按厚度加权的渗透率几何平均值小于或等于按厚度加权的渗透率算术平均值。这表明, 在测井解释或地质模型对渗透率粗化时, 不同的粗化方法所得的粗化渗透率值不同。

Permeability Up-Scaling Method Based on the Relationship Between Porosity and Permeability

Permeability can be estimated using the porosity from logging interpretation and the porosity-permeability model from the core analysis. Permeability up-scaling can be done by the thickness weighted-average method or the geometric average method. This paper first proved that, permeability calculated from the thickness weighted averaged porosity and the porosity-permeability model is equal to that obtained from the geometric average method, rather than that from the thickness weighted-average method. It also proved that the geometric averaged permeability is less than or equal to the thickness weighted-average one. This shows that different up-scaling methods lead to great different permeability values.