ArcGIS中GPS速度场的框架旋转和制图表达的设计与实现

The Terrestrial Frame Rotation and Geographic Representation of GPS Velocity Field Based on ArcGIS

GPS速度场反映区域的地壳变形特征,而目前主流的GIS平台缺少GPS速度场的制图表达,不利于和现有的矢量和栅格数据进行叠加分析。利用ArcGIS为Python提供的Arcpy/Arcgisscripting模块实现速度矢量图形的输出。具体处理过程需要编写代码对选定站点速度进行欧拉矢量计算,实现框架旋转变换,以突显差异运动特征;还包括指定置信度的误差椭圆计算。输出shape文件包括GPS点文件,其属性表为输入速度数据,以及矢量箭头线文件和误差椭圆线文件。最后以中国大陆及周边GPS连续观测站的计算结果,旋转变换到欧亚框架下,实现GPS速度场在ArcGIS中的制图表达。

GPS velocity field can reveal crust deformation information. However, the geographic representation of GPS velocity is not provided by Geographic Information System （GIS） itself. So, it is difficult to overlap analysis with vector and raster data in GIS directly. The velocity vector graphics are plotted with module Arcpy / Arcgiss- cripting in ArcGIS through Python. The process introduced in detail consist of two major parts. One is terrestrial frame Rotation, the other is error ellipse calculation. The GPS data creates in shapefile containing velocity point, vector arrow polyline and error ellipse polyline. The GPS velocity patterns of China mainland and beyond are mapped in ArcGIS with continuous GPS observation.