A near-surface seismic scattered wave separation method

Abstract

Considering that near-surface scattered waves could not be suppressed by conventional denoise method, this paper analyzes the characteristics of scattered waves and achieves the near-surface scattered wave separation by the seismic interferometry theory. Seismic data in mountain area is generally characterized by low signal to noise ratio, weak effective wave energy and strong near-surface scattered wave energy, so the near-surface seismic scattered waves must be firstly separated to improve the signal to noise ratio of seismic data during seismic data processing. The events of the near-surface seismic scattered wave in the adjacent common shot gathers are parallel. According to the near-surface scattered wave kinematics, the seismic interferometry method is used to eliminate the influence of seismic wave propagation in the same path, coherently enhance near-surface scattered waves, and then separate them from original seismic records. Taking the seismic data in mountain area in west China as an example, the energy of near-surface scattered wave is enhanced by direct wave field and full wave field seismic interferometry to separate the waves. As a result, the seismic data after processing generally eliminates near-surface scattered waves, verifying the validity and feasibility of the near-surface seismic scattered wave separation method. Key words: mountain seismic exploration, near-surface, seismic scattered wave, scattered wave separation, seismic interferometry