Wavelet analysis approach to de-noising of magnetic data
Abstract
A new de-noising technique using Wavelet Analysis to remove unwanted signal (noise) from an aeromagnetic data set is compared to the conventional techniques of Fourier analysis, 4th difference and Naudy filtering. The new Wavelet Analysis approach of thresholding coefficients of the Wavelet Transform on wavelet levels where noise is considered present produces a superior de-noised product. Noise which is composed of 1/m integer multiples of the significant features in the data observations (i.e. the three point spike), are easier to remove. This method can be extended to other geophysical procedures such as mineral exploration magnetic bore-hole logging where noise often constitutes a large portion of the overall signal.