An Effective True-Amplitude Gaussian Beam Migration via Illumination Compensation

Abstract

Summary Conventional migrations are apt to structure imaging, but often incapable of generating true-amplitude subsurface image. We propose a true-amplitude Gaussian beam migration (GBM) method under the framework of seismic illumination compensation. A novel scheme based on the GBM is developed to estimate the point spread functions, with which the illumination compensation can be efficiently implemented in the local wave-number domain. The total computational cost of the proposed true-amplitude imaging includes one Born modelling process and two conventional GBM processes, which is more efficient than the true-amplitude imaging using least squares migration which requires multiple iterations. Numerical examples using synthetic data demonstrated the effectiveness and efficiency of the proposed method.