Multicomponent Time-Frequency Noise Attenuation of Microseismic Data

In this paper, we introduce a novel compound filter that is suitable for multicomponent seismic data. The objective of the new filter is to enhance the data signal-to-noise ratio while preserving polarisation information. A combination of three filters is used to achieve this. The first of these filters is a polarisation filter which is applied to pre-condition the seismic data. This step is followed by the application of the second filter, which is an adaptive multicomponent block-thresholding technique. One of the advantages of this filter is that it preserves polarization, while reducing the noise in each of the recorded components. Because it operates in the time-frequency domain, this filter can benefit from the potential separation between signal and noise that can occur in such a domain. The results obtained from the application of this method are used to build the third filter, an optimal Wiener filter. We demonstrate the efficacy of our new technique on synthetic and real microseismic data. In the synthetic data examples, the signal-to-noise ratio improvement was measured in the range of 8-12 dB, while the polarisation was preserved.