基于波数域上Fourier变换的磁异常信号处理

Magnetic Anomaly Data Processing Based on Fourier Transform in Wave Number Domain

针对不同使用目的所需的磁异常信号数据的采集和处理,和目前空间域处理方法的精度不足等问题,提出了对空间域的磁异常数据进行频谱分析后,在波数域上推导TMI、磁场三矢量和磁梯度张量等数据之间关系的解析方法,并在实验数据中填充插值算法,得到了噪声更小、更清晰、分辨率更高的磁异常信号数据,有利于之后的磁异常解释和应用。首先介绍了空间域上的推导公式,然后简述已经在波数域上建立的数学框架,着重推导波数域上不同磁异常数据的变换关系,并用反距离加权算法对采集的实验数据进行处理,以取得圆滑的网格。最后对实测数据的处理证明,相较于空间域上的推导和解释,本方法可以得到质量更好的磁异常数据。

For the collection and processing of magnetic anomaly signal data required for different purposes,and the lack of precision of the current spatial domain processing method,a method which use the the magnetic anomaly data in the wavenumber domain after spectral analysis is proposed to deducethe relationship among the TMI,magnetic field three vector and the magnetic gradient tensor,in the meantime,the interpolation algorithm is filled in the experimental data. In the end,the magnetic anomaly signal data with smaller noise,clearer and higher resolution is obtained,which is beneficial to the subsequent magnetic abnormal interpretation and application. Firstly,the derivation formula in the spatial domain is introduced. Then,the mathematical framework that has been established in the wavenumber domain is briefly described. The transformation relationship of different magnetic anomaly data in the wavenumber domain is deduced,and the experimental data collected is processed by the inverse distance weighting algorithm to get a sleek grid. Finally,the processing of the measured data proves that the method can obtain better magnetic anomaly data than the derivation and interpretation in the spatial domain.