Kriging插值方法在地层模型生成中的应用

Kriging interpolation and its application to generating stratum model

为了建立三维数字地层,采用了一种适合城市工程地质和岩土工程特点的地层数据模型-基于钻孔信息的3棱柱模型。由于钻孔之间的距离稀疏程度、方向、数据值存在差异,钻孔以外未知的地质特性需要插值和推断,传统的数理统计方法无法很好地解决空间样本点的选取、空间估值和2组以上空间数据的关系等问题。借鉴地质统计学的Kriging方法给出一种距离加权插值算法,即先根据空间数据得到统计特征,再根据统计特征进行插值。通过对地层模型插值结果的观察,得出该算法可以获得良好的插值效果。

In order to generate 3-dimensional digital stratum, a stratum data model of tri-prism is presented based on borehole data, which is applicable to urban geological engineering and geotechnical engineering. Due to the variant distribution and different attributive values among boreholes, the geological properties at unknown locations have to be estimated or interpolated by some special methods. However, common statistical methods could not resolve such problem which includes selection of sample points, spatial estimation and comparison of bilateral data. A distance-weighted interpolation method for scattered borehole data points is proposed, which exploits the Kriging method in geostatistics. On the premise that the distributed statistics characters of the spatial borehole data are obtained at first; according to the distributed statistics characters, the spatial interpolation is presented successively. Case study shows that the generation of 3-dimensional stratum by proposed interpolation methods can gives a good result.