摘要
分析标准Poisson核函数和Molodensky-Poisson核函数特性,并计算其远区效应的截断误差,获取与延拓高度、积分半径和截断阶次的关系。分析认为,Molodensky-Poisson核函数能够抑制远区的影响,当延拓高度不高于3km,积分半径至少0.5°时,其截断误差在1mGal以内;当积分半径为1°时,其截断误差在10μGal量级,可满足计算1cm大地水准面目标的要求。
This paper attempts to achieve accurate results for the downward-continuation.In the paper the detailed characters of the standard Poisson kernel and the Molodensky-Poisson kernel are analyzed.The truncation error of the far-zone contribution is estimated.The relations of the height,the truncation radius and degree are analyzed in the downward-continuation of the gravity anomalies.The results suggest that the Molodensky-Poisson kernel can reduce the far-zone contribution.The height is less than 3km and the truncation radius is more than 0.5°.The truncation error estimated at less than 1mGal;when the truncation radius reaches 1°,the truncation error estimate achieves an accuracy of 10μGal.Hence it ensures the accuracy of the geoid reach to the 1cm level.
引文
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