重力向下延拓计算分析

Calculation and analysis of gravity downward continuation

随着重力测量数据的丰富,重力向下延拓成为需要解决的问题。研究利用Poission公式进行重力场向下延拓方法,该方法需要进行迭代计算,模拟数据以EGM2008计算的地球表面上的重力观测值延拓到大地水准面上。模拟实验结果表明,对于地势复杂区域需要迭代次数比地势平坦区域要多,并且迭代效果较差,向下延拓后的重力起伏更加明显,是一个误差放大的过程。

With plenty of the gravity measurement data, gravity downward continuation becomes a problem needed to be solved. Poission formula is used to study gravity downward continuation, which requires the iterative calculations. EGM2008 is used to calculate the Earth＇s surface gravity observations extented to geoid surface. The simulation results show that the number of iterations required for the complex topography region is more than the flat area, iteration is less effective, and gravity fluctuation with downward continuation is more apparent because of which is an error amplified process.