Kriging方法在GPS速度场网格化和应变率场计算中的适用性

The Applicability of Kriging Interpolation Method in GPS Velocity Gridding and Strain Calculating

从Kriging方法的基本原理出发，推导了Kriging球面应变计算公式，通过在模拟和实际GPS数据中的试算，讨论了该方法在区域GPS速度场网格化和应变率计算中的适用性。结果表明Kriging方法对GPS速度场滤波和网格插值是可行的，交叉检验及残差分析结果亦表明了Kriging方法的有效性。对比Kriging方法与最小二乘配置方法对中国大陆1999~2004期GPS速度场处理结果，发现两种方法的滤波和网格化效果相当；而应变率场结果总体分布相近，但Kriging结果自身一致性不佳，最大剪应变率的高值区是一致的，但量级上差别显著；Kriging应变率计算方法在抗差性和边缘效应处理方面不如最小二乘配置方法。

In this article, we derive a spherical strain Kriging formula based on the basic theory of Kriging, and applied it to simulated and real GPS data. We analyzed its difference with the least-square collocation method. Crosscheck results indicate that Kriging interpolation is feasible and valid in GPS velocity smoothing and gridding. The Kriging strain results reveal low robustness and obvious edge effects, but the smoothed and gridded results for GPS velocity data during 1999-2004 from Kriging interpolation methods are in agreement with the results calculated by the Least-square collocation method. The strain rate results from the two meth- ods are similar in the whole distribution characteristic, however, the kriging results show low self-consistency. In a word, the Kriging strain method is not as good as the least-square collocation method for robustness and edge effect.