用 X^2(n)分布研究毛管压力曲线及对八区乌尔禾巨厚砾岩油藏的研究

A STUDY OF THE CAPILLARY CURVE OF THE THICK CONGLOMERATIC RESERVOIR IN THE 8TH BLOCK,KARAMAY OIL FIELD,XINJIANG,BY X^2(n) DISTRIBUTION AND ITS GEOLOGICAL SIGNIFICANCE

本文从基本概率理论出发,严格建立了一套 X^2(n)分布的计算公式和标准图版,介绍各种特征参数的确定方法。用 X^2(n)分布研究毛管压力曲线,获得解释储层所含孔隙特征的 n~*和用于估算渗透率、解释 J 函数的岩性因素 F_(?)。详细地讨论了这两个参数的地质意义。用此方法研究克拉玛依油田八区乌尔禾储层获得了良好的结果。理论证明它不仅适合于这类特殊油藏的储层,而且可推广到其它常见油藏,将同样获得有地质意义的 n~*和 F(?)值。布鲁克斯(Brooks)和科雷(Corey)分布特征仅属 X^2(n)分布的特例(n~*=2)。

Based on the theory of probability this paper gives a set of formula and related normalized charts for the determination of the characteristic parame- ters.A study of capillary curve by a X^2(n) distribution can obtain the pore characteristics,n~*,and the lithological factor F_c for the estimation of perme- ability.The geological significance of these two parameters are discussed in detail.This technique is used to study the Wuerhe reservoir in 8th block, Karamay oil field and satisfactory results are obtained.It is proved theoreti- cally that this technique when it is used to study other types of reservoir can yield n~* and F_c with geological significance.It is shown also that both Brooks and Corey distribution are special case of X^2(n) distribution (n~*=2).