重力地形改正的计算模型研究

Research on the terrain correction models in gravity survey

为了比较分析地形改正两种模型间的差异及不同地形对地形改正的影响,采用我国4类不同地形的DTM数据,分别使用质量棱柱地形模型和质量线地形模型计算这4个区域的地形改正误差,发现由这2种模型计算得到的地形改正量间的差异很小;研究了平地、丘陵、山地和高山4种地形对地形改正误差的影响,地形改正误差与地形起伏变化强相关;考虑到3阶结果有可能不收敛,2种地形改正模型的傅里叶变换核函数分母取至2阶为宜。

For comparing and analyzing the difference between terrain correction models： Mass-Prism model and Mass-Line model,and the correction results by different topography,the paper employed four topography＇s DTM data;calculated their terrain correction by Mass-Prism model and Mass-Line model;the result verified that the value corrected by Mass-Prism model was close to Mass-Line model.Researched the relation between terrain correction and topography including plain,hilly,mountain and alpine country,the terrain correction error was related to topographic relief.After volume tests,because 3 order might lead to divergence results,the Fourier transformation kernel function＇s denominator should take 2 order.