椭圆窗方向滤波器在重力资料处理中的应用

由于引入了快速傅氏变换的计算方法,重磁资料的数字处理由过去单一的空间域处理,引伸到空间域、频率域两大系统。两者之间取长补短,相辅相成,对于提高处理及解释水平的作用日益显著。频谱理论和模型试验表明,地质体产生的重磁力异常的走向,与在频率域内其异常的频谱走向相互垂直。根据重磁场频谱的这一方向特性,可以设计出各种各样的方向滤波器。本文利用椭圆窗上两个半轴(长、短轴)不等及椭圆圆心的位置(滤波器的中心频率),即椭圆窗方向滤波器来加强与压制两个不同方向上的信号。实例表明,这种滤波器可以有效地对三度体产生的异常进行滤波,特别是对走向不同的局部场与区域场,有明显的分离效果。

The application of directional ellipse filter to gravity data processing

Fast Fourier transform advances the gravitational and magnetic data processing from single space domain to frequency domain, The two domain processing systems make up each other"s deficiencies and supplement each other, thus obviously improving the processing and interpretation techniques. The frequency spectrum theory and experimental model show that the trends of gravitational and magnetic abnormals caused by geological body are perpendicular to the trends of the frequency spectra of the abnormals in frequency domain, Various directional filters can be designed according to the directional characteristic of the frequency spectra of gravitational and magnetic fields. The signals on two different directions are enhanced or attenuated by the directional ellipse filter, that is to say, by the length difference of its a and b axes as well as the ellipse center position (i. e.the center frequency of the filter.This filter can effectively filter 3D abnormals;particulary, it can identify the local and regional fields whose trends are different.