多元逐步回归分析在评价孔隙结构对低渗透砂岩储层质量影响中的应用

以鄂尔多斯盆地姬塬地区长2油层组低渗透砂岩储层实际数据为例,利用多元逐步回归分析方法建立了孔隙结构对低渗透砂岩储层孔隙度、渗透率影响的多元回归模型。计算结果表明：孔隙度=18.578-2.897×排驱压力-0.376×结构系数（r=0.739）,反映了排驱压力、结构系数是影响低渗透砂岩储层孔隙度的主要孔隙结构因素;ln（渗透率）=10.781＋9.614×变异系数-0.341×结构系数-1.007×孔喉均值（φ）（r=0.973）,反映了变异系数、结构系数、孔喉均值（φ）是影响低渗透砂岩储层渗透率的最主要孔隙结构因素。

Application of Multiple Stepwise Regression to Influential Evaluation of Pore-Throat Size on Low-Permeability Sandstone Reservoirs

Based on the data from the low-permeability sandstone reservoirs of the Chang 2 oil-bearing bed from Jiyuan of Ordos Basin,the multiple stepwise regression analysis method is used to establish two multiple regression equations in the influential evaluation of the pore-throat sizes on the porosity and permeability of the low-permeability sandstone reservoirs：porosity=18.578-2.897×entry pressure-0.376×texture coefficient（r=0.739）.This equation indicates that the entry pressure and texture coefficient are important factors to the porosity of the low-permeability sandstone reservoirs.ln（permeability）=10.781＋9.614×variation coefficient-0.341×texture coefficient-1.007×mean pore-throat（）（r=0.973）,this equation indicates that the variation coefficient,texture coefficient and mean pore-throat（） are the most important factors to the permeability of the low-permeability sandstone reservoirs.