地壳中化学元素含量的空间分布构成了三维空间中的一个曲面,称之为地球化学面(geochemicalsurface)。地球化学面的形态依赖于采样网格(采样密度)的大小而变化,因而是不确定的。采样的密度减小,得到的地球化学面会相应地简单,采样的密度增大,得到的地球化学面亦会更加复杂。这就象测量海岸线的长度是依赖于测量时使用的尺度因而是不确定的一样,因为海岸线是弯曲的,而每个弯曲中 The spatial distribution of chemical elements in the earth’s crust constitutes a surface in three-dimensional space, termed the geochemical surface. The shape of the geochemical surface varies depending on the size of the sampling grid (sampling density) and is therefore indefinite. Decreasing the sampling density will result in a correspondingly simpler geochemical profile, an increased sampling density and a more complex geochemical profile. This is as uncertain as measuring the length of a coastline depending on the scale used in the measurement, as the coastline is curved and in each bend