中国大陆GPS速度场的球面小波模型及多尺度特征分析

摘要

The GPS measurements of the Crustal Movement Observation Network in China (CMONC) from 1999 to 2009 were processed ,and the velocities of 1068 stations in east and north directions were derived . These velocities were used to establish velocity models in east and north directions within mainland China by using Difference of Gauss (DOG) spherical wavelet .The trend of GPS velocity fields are derived by regional Euler vector method ,the residual velocity fields are then used for the spherical wavelet modeling . The scales of wavelets are selected according to distributions of GPS stations .The accuracy of the model isestimatedaccordingtothemeansquaredeviationbetweenobservationsandmodel ,whichis ±09.5mm/a for east direction , and ± 0 9.7 mm/a for north direction in the region with dense stations , while it is ± 1 3.2 mm/a and ± 1 3.0 mm/a respectively for east and north directions in the region with sparse stations . The spherical wavelet modeling of the velocity can also show characteristics at different scales .%利用1999—2009年间中国大陆共1068个GPS站点在东方向、北方向的速度值，采用DOG球面小波多尺度分析方法，建立了中国大陆东方向、北方向多尺度速度场。球面小波模型的尺度主要根据观测站点的密度来确定，利用检核点上的已知速度与模型速度之间的均方差来评定模型的精度。利用球面小波模型可以更加清晰地表示速度场的大尺度特征和复杂的局部变化特征。站点稠密区域，模型在东方向、北方向上的精度分别为±09．5mm／a、±09．7mm／a，稀疏区域对应的精度分别为±13．2mm／a和±13．0mm／a。