重力异常垂直梯度中央区效应的精密计算

为提高利用重力异常计算重力异常垂直梯度中央区效应的精度,视中央区为矩形域,将重力异常表示成双三次多项式插值形式,引入非奇异变换,推导出了重力异常垂直梯度中央区效应的精密计算公式。以低纬度区域分辨率为2＇×2＇的重力异常数据为背景场进行了仿真分析,结果表明在解算计算点所在的1个网格的中央区效应时,传统公式与本文导出公式计算结果差值的最大值达数E。该导出公式可为重力异常垂直梯度中央区效应的精密计算提供理论依据。

The Precise Calculation of the Innermost Area Effects of Vertical Gradient of Gravity Anomaly

In order to improve the precision of the innermost area effects in the computation of vertical gradient of gravity anomaly using gravity anomaly,gravity anomaly is expressed as double cubic polynomial regarding the innermost area as a rectangular one,and the precise formulae to calculate vertical gradient of gravity anomaly in this area are derived after the non-singular transformation is introduced.A simulation is done based on gravity anomaly data with a resolution of 2′×2′ in a low latitude area.The results indicate that the maximal differences in the innermost area effects of only one grid including the calculation point calculated by traditional and this paper＇s formulae respectively are several E.The formulae derived in this paper could provide theoretical basis for the precise computation of the innermost area effects of vertical gradient of gravity anomaly.