An Improved GB Decomposition Method Based on Genetic Algorithm
详细信息
- 责任者：Yin Yaotian (Geodetection Laboratory of the Ministry of Education ; China University of Geosciences ; Beijing 100083 ; China) ; Wei Wenbo
- 刊名：Chinese Journal of Geophysics
- 出版年：2012
- 卷期：55(2)
- 关键词：大地电磁法 ; magnetotelluric methods
- 页码：p.671-682
- 图表：11 illus., 2 tables, 22 refs.
- 分类号：1600
- issnNo：ISSN0001-5733
- isbnNo：CN11-2074/P
摘要
The galvanic distortion analysis approach advocated by Groom and Bailey has become the most adopted method.As proposed by Groom and Bailey,one must determine the appropriate frequency-independent telluric distortion parameters and geoelectrical strike direction by fitting the seven-parameter model on a frequency-by-frequency and site-by-site basis independently.Although this approach has the attraction that one gains a more intimate understanding of the data set,it is rather easy to be tapped into a local minimum before reaching the global minimum by using a traditional optimization methods(e.g.Least square method or Gauss Newton method) when conducting the repetitive application.In this paper,we improved GB decomposition method by Genetic Algorithm firstly,then tested the reliability of this new GB decomposition method by decomposing the synthetic data and data generated by forward modeling.Lastly,we applied it into the studying of the structure strike of an area in Northern Qinghai Tibetan Plateau and obtained results consistent with the results of previous geological and geophysical work.What′s more,multifrequency GB decomposition and MT static shift correction method have also been studied and their validity has been verified by practical MT data test.