This paper describes the application of stepwise regression analysis to calculate porosity of rocks from well log data.If we assume: the porosity (φ) is dependent variable, the acoustic velocity time difference (△t), nature Gamma (GR) and nature electrical potential (a) are three independent variables. The binomial expansion is used in the calculated procedure, and two new independent variables are added on the basis of explanatory theory and practical experience of well log, through stepwise calculation, we get the following equation:Thus, using this approximation expression mentioned above, we may make up quantitative explanatory map board of porosity of rocks.Interior , interpolation accuracy joined in statistical samples is 93.8%.Average predictive accuracy appllied to a porosity map board to the oil field is91%.
. 1980, 应用逐步回归建立岩石孔隙度图版. 地质科学, 15(2): 186-193.
. THE USE OF STEPWISE REGRESSION TO MAKE UP MAP BOARD OF LITHOLOGIC POROSITY[J]. Chinese Journal of Geology, 1980, 15(2): 186-193.