Downward continuation of airborne geomagnetic data based on two iterative regularization methods in the frequency domain  

作　　者：Liu Xiaogang Li Yingchun Xiao Yun Guan Bin 

机构地区：[1]Xi'an Research Institute of Surveying and Mapping [2]State Key Laboratory of Geo-Information Engineering [3]Key Laboratory of Geo-space Environment and Geodesy of Ministry of Education, Wuhan University

出　　处：《Geodesy and Geodynamics》2015年第1期34-40,共7页大地测量与地球动力学（英文版）

基　　金：supported by the National Natural Science Foundation of China(41304022,41174026,41104047);the National 973 Foundation(61322201,2013CB733303);the Key laboratory Foundation of Geo-space Environment and Geodesy of the Ministry of Education(13-01-08);the Youth Innovation Foundation of High Resolution Earth Observation(GFZX04060103-5-12)

摘　　要：Downward continuation is a key step in processing airborne geomagnetic data. However,downward continuation is a typically ill-posed problem because its computation is unstable; thus, regularization methods are needed to realize effective continuation. According to the Poisson integral plane approximate relationship between observation and continuation data, the computation formulae combined with the fast Fourier transform（FFT）algorithm are transformed to a frequency domain for accelerating the computational speed. The iterative Tikhonov regularization method and the iterative Landweber regularization method are used in this paper to overcome instability and improve the precision of the results. The availability of these two iterative regularization methods in the frequency domain is validated by simulated geomagnetic data, and the continuation results show good precision.Downward continuation is a key step in processing airborne geomagnetic data. However,downward continuation is a typically ill-posed problem because its computation is unstable; thus, regularization methods are needed to realize effective continuation. According to the Poisson integral plane approximate relationship between observation and continuation data, the computation formulae combined with the fast Fourier transform（FFT）algorithm are transformed to a frequency domain for accelerating the computational speed. The iterative Tikhonov regularization method and the iterative Landweber regularization method are used in this paper to overcome instability and improve the precision of the results. The availability of these two iterative regularization methods in the frequency domain is validated by simulated geomagnetic data, and the continuation results show good precision.

关 键 词：Downward continuation Regularization parameter Iterative Tikhonov regularization method Iterative Landweber regularization metho 

分 类 号：P318.6[天文地球—固体地球物理学]