Diffraction Separation and Imaging Using Damped Multichannel Singular-Value Spectrum Analysis
P. Lin, S. Peng, J. Zhao and X. Cui
Event name: 81st EAGE Conference and Exhibition 2019
Session: Poster: Diffraction Imaging & Modelling
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 1.12Mb )
Price: € 20
Seismic diffractions are the responses of small-scale discontinuous structures and contain subwavelength geologic information, thus they have the capability of high-resolution imaging. However, the energy of diffractions is generally much weaker than that of reflections and diffractions are likely to be masked by strong specular reflections. Diffraction separation is the first key step for accurate diffraction imaging. In this study, we propose a new alternative method based on damped multichannel singular-spectrum-analysis (DMSSA) algorithm for diffraction separation and reflection suppression. The DMSSA algorithm combines the differences of the kinematic and dynamic properties between reflections and diffractions to suppress strong linear reflections and separate weak hyperbolic-type diffractions in common-offset or poststack domain. The magnitudes of singular values are proportional to the energy strength of signals. The stronger the energy of a component of the signals, the larger the corresponding singular values. The singular values of reflections and diffractions have dissimilar spatial distributions in singular-value spectrum because of the differences of energy and linear properties. We use synthetic and field data examples to test the validity of the proposed method and the results demonstrate its good performance in enhancing diffractions and suppressing reflections.