A comparison of effects between the iteration method and FFT for downward continuation of potential fields

作者：Xu Shi Zhe^*

来源：Chinese Journal of Geophysics, 2007, 50(1): 285-289.

• downward continuation of potential field
• space domain
• iteration method
• frequency domain
• FFT

The values of a potential field measured on a horizontal plane are projected on a lower horizontal plane to be continued as initial values of the field. With these initial values on the continuing horizontal plane, the potential field on the original plane is calculated using the Fast Fourier Transformation (FFT). A correction is then made in the potential field on the continuing plane based on the difference between the observed and calculated values of the potential field on the original plane. The process is iteratively repeated until the differences become negligible. The principle of this iteration method in space domain is very simple. It does not require solving algebraic equations and possesses a high computation speed with a reasonable accuracy. The downward continuations are made by the iteration method and the FFT for a model and practical data, respectively. The effect of the iteration method is much better than the FIT.

• 出版日期2007-1
• 单位浙江大学