地层特性随机场插值方法应用研究

Application study of spatial interpolation method in geological random field

地质勘探中钻孔的数量常是有限的,钻孔以外未知的地质特性需要进行插值或推断。实践中一般假定两钻孔之间的地质特性为线性分布,用直线连接。线性连接方法简单,但精度难以保证。因此,有必要进一步研究简便且精度高的插值方法。对常用的空间插值数学方法作一简要评价,认为 Kriging 法更适用于地质特性随机场的插值。并尝试将 Kriging 法应用于南水北调穿黄工程砂土地基标准贯入击数及液化范围的空间插值,采用合适的变差函数以反映砂层的空间相关特性,由插值结果得到地基砂层标贯击数及液化范围的沿线分布,从而可以更好地了解地层特征的变化情况。

The number of exploratory hole is usually limited in geological investigation. The unknown geological properties between exploration holes have to be estimated or interpolated by some special methods. Linear connection between explored points is generally used in practice with its simplicity but sometime low accuracy. How to develop convenient and accurate interpolation methods remains an interesting problem in geosciences. Some commonly used spatial interpolation methods are commented in this paper through principal analysis. The Kriging method is thought to be unique and more reasonable with its best use of geological investigation information. As an application attempt, Kriging method is applied to interpolate the spatial distribution of standard penetration number for a liquefiable sandy stratum. Comprehensive understanding about the geological properties of the stratum is derived from the interpolation.