Separating the Near‐Surface Seismic Scattered Waves Using Seismic Interferometry Method

Abstract

AbstractIt is important to separate the near‐surface seismic scattered waves from low signal‐noise data in mountain seismic exploration, and seismic interferometry is one of promising methods. The seismic interferometry representations of the near‐surface scattered wave are derived according to the seismic interferometry theory and the scattering theory. Those representations are composed of interferometry between actual wavefield and background wavefield and include cross‐correlation type and convolution type seismic interferometry expression. According to the near‐surface scattered wave separation theory and the geometry of land seismic exploration, the mixed configuration of convolution type and deconvolution type seismic interferometry is used. The application effect of the near‐surface scattered wave method is showed using the real land seismic data. The theoretical analysis and real data tests in gravel area indicate that the seismic interferometry method can separate not only scattered wave generated by scattering sources on survey lines, but also partial side scattered wave. The advantages of this technology are that it adapts to the uneven terrain and the complex near‐surface structure without information about topography and near‐surface velocity. In this article, the subtraction method of multi‐traces self‐adaptive matched filter is used to eliminate the near‐surface scattered wave from the real seismic data, and gets preferable results in gravel area.