利用小波变换压制静态效应的方法

The application of wavelet transform to suppressing static effect

利用有限元大地电磁二维正演程序模拟了二层大地低阻静态效应的地电模型,研究了静态效应产生的原理及其影响,并利用小波变换方法对静态效应进行压制,相对于其他常规空间滤波法来说,取得了较好的压制效果,证实了小波变换方法在压制静态效应当中的可行性和有效性。用小波变换方法对某工区实测EH-4音频大地电磁资料数据进行分析、处理,从数学上识别和判断了静态效应,在较好地压制静态效应的同时又能较好地突出地层原本的地质异常。

In this paper, the magnetotelluric two-dimensional finite element forward modeling program was used to simulate a two-floor earth geoelectric model of low resistance static shift and study the principle of Static shift and its impact. The wavelet transform was also used to suppress the static shift. In contrast to other conventional spatial filtering methods, the method adopted by the authros can obtain a better suppression result, thus confirming the feasibility and effectiveness of applying the wavelet transform method to suppressing the static shift. Finally, the authors used the wavelet transform method to analyze measured EH-4 data in a work area, identified and determined the static shift from the mathematical model. It is shown that wavelet transform method for data processing can attain a good suppression. This method can retain the original layered structure information and local anomalies caused by the geological anomaly body while suppressing the static shift.