Removing coherent noise in the seismic with Cegal Blueback Avary

Coherent noise in the form of stripes can greatly affect the quality of data and it is not easy to remove. Cegal Blueback Avary offers innovative ways to handle this problem effectively.

The term 'de-striping ' in Cegal Blueback Avary (Avary) refers to the process of removing coherent noise in seismic that manifests itself as stripes or ribbons in the results after trace stacking. This type of noise can greatly affect the quality of subsequent processing during both structural and stratigraphic interpretation. The calculation of other seismic attributes can be greatly affected by this type of noise. In many cases, this noise is barely visible to the eye in horizontal sections and especially in the deeper parts, however, it is present and negatively affects the quantification of the seismic data.

Fig. 1: Inline section showing strong stripe patterns.

Avary offers methods to effectively reduce this type of noise. Using a 2D Fourier method, noise patterns can be visualized in a 2D Fourier space. This allows very accurate masks to be generated to counteract very detailed noise from the stripes. 

Fig. 2: Slice section at 300ms before and after applying the 2D Fourier filtering.

The result of this process is most effectively seen when displaying a slice using spectral decomposition (SD). The two-dimensional Fourier filter has been able to effectively clean up the noise, allowing a clearer identification of the geological events. 

Fig. 3: SD image improved (below) after applying Avary´s de-striping.