Neighbourhood algorithm and its application to 1D magnetotelluric data inversion
HUANG Wei-Hang1,2, JIN Wei-Jun1, ZHANG Wen-Hui1,2
1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China
Magnetotelluric method (MT) is applied so widely that improving the method of inversion and the interpretation of MT data become very important. This paper summarizes different inversion algorithms and points out their limitations. Then an overview is given on neighborhood algorithm (NA) and its application to the MT inversion. The maximum likelihood model from NA is very close to the theoretical model. Although NA and genetic algorithm (GA) have the same capability for resisting the local minimum value, NA algorithm shows better similarity between the density distribution of sampling points and the error function, so NA is more conducive to inversion application based on the integral parameter appraisal method. In this study, the authors found that NA converges much faster than GA, whereas NA algorithm is more advantageous than GA algorithm in 1D MT inversion.
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