静态效应的小波阈值法和EMAP校正在EH-4数据处理中的应用

Correction the static effect of EH-4 data by EMAP and wavelet analysis

电磁阵列剖面法(EMAP)和小波分析在压制静态效应中都得到了不同程度的应用,取得了很好的效果.对于EMAP方法,由于它在加窗的过程中,其窗宽是受到了静态效应影响的Bostick反演深度,在某种程度上影响了它的处理效果.小波分析通过小波变换模极大值与Lipschitz指数相结合对信号奇异性进行判断,能够准确确定畸变信号的位置,再通过低通滤波处理达到有效的消除静态效应,将高频部分完全滤除,它也存在校正不足和过校正现象.笔者在此基础上讨论阈值的选取对小波分析压制静态效应的影响,从小波分析方法的阈值处理着手,选用不同的阈值方法,通过仿真和实测数据处理比较了它们在静态效应中的应用,并对安徽某矿区的实测数据进行了处理,结果表明小波阈值法和EMAP都能很好的压制静态效应.与EMAP比较,小波分析在静态效应的识别上有相对的优势.

Electromagnetic array profile method(EMAP) and wavelet analysis were applied to different levels in suppressing static effects,and good results were achieved.For the EMAP method,its window width was affected by the static effect,and the depth of Bostick inversion was affected to some degree.Through the analysis of wavelet modulus maxima of wavelet transform combined with Lipschitz index to judge the signal singularity,it can accurately determine the position of the signal distortion,and then through the low-pass filter to eliminate the static effect effectively,eliminate the high frequency part,it also had insufficient correction and over-correction phenomenon.This paper discussed the selection on the basis of analysis on the effect of suppressing the static effect of wavelet threshold,the wavelet analysis method was used to select the threshold processing.Application of simulation and measurement data processing of two methods were compared in static effect,and the actual data of Anhui mining area of processing results showed that the wavelet threshold method and EMAP can eliminate the static effect is good.Compared with EMAP,wavelet analysis had relative advantages in the recognition of static effects.