The spectral stacking method and its application in seismic data resolution increase

Abstract

Preconditioning is a practice adopted in the treatment of seismic data and, when properly applied, favours a resolution increase. However, retrieving all the frequency contents is still a challenge to overcome. Techniques to improve the seismic resolution should preserve the existing relations in the distribution of seismic events. Otherwise, it may cause undesirable situations, from the degradation of the signal-to-noise ratio to the creation of false events, leading to errors of interpretation. We developed a method called spectral stacking, which makes use of circular convolution in the frequency domain to extend frequency content, preserving the distribution of seismic events without adding artefacts. As an application of the spectral stacking method, we create a sharpening filter that resolves layers under Ricker's criterion. In addition, the sharpening filter preserves the amplitude using a variable-window correction based on the local minima of the absolute values of amplitude. We validated our proposed method in synthetic and real tests. The results showed that the sharpening filter obtained a resolution increase, providing a sharper image of the seismic section.