Taking the Triassic Chang 8 Member of Ansai Region,Ordos Basin as an example,two T2 cutoff were chosen to classify the T2 spectra into three parts,which are defined as the pores with small pore size,median pore size and large pore size,separately.The percentage compositions of small pore size,median pore size and large pore size were calculated.Combining with NMR total porosity,T2 geometric mean(T2lm)and the percentage compositions of small pore size,median pore size and large pore size,a parameter,which is named as formation effective index(NVI)and used to reflect tight sandstone reservoir pore structure,is established,and it is used to quantify formation validity.Relationship between NVI and oil displacement index is analyzed,and the target tight sandstone reservoirs are categorized into three types.
关键词
核磁共振测井/储层有效性/分级预测/致密砂岩
Key words
nuclear magnetic resonance(NMR)logging/formation validity/formation type prediction/tight sandstone reservoirs
维普
万方数据