Abstract First-arrival slope tomography (FAST) introduces first-arrival slopes, corresponding to the horizontal components of slowness vectors, at receiver and source positions supplement traveltime for better guiding ray propagation in media until best match is achieved with observed data. FAST can recover velocity model higher resolution precision than (FATT) but computationally intensive. In...

Stacking plays an important role in improving signal-to-noise ratio and imaging quality of seismic data. However, for low-fold-coverage seismic profiles, the result of conventional stacking is not always satisfactory. To address this problem, we have developed a method of stacking in which we use local correlation as a weight for stacking common-midpoint gathers after NMO processing or common-i...

Spatial aliasing in multichannel seismic data can be overcome by solving an inversion in which the model is the section that would be recorded in a well sampled zero-offset experiment, and the data are seismic data after normal moveout (NMO). The formulation of the (linear) relation between the data and the model is based on the wave equation and on Fourier analysis of aliasing. A processing se...

We present a migration velocity analysis (MVA) method based on wavefield extrapolation. Similarly to conventional MVA, our method aims at iteratively improving the quality of the migrated image, as measured by the flatness of angle-domain commonimage gathers (ADCIGs) over the aperture-angle axis. However, instead of inverting the depth errors measured in ADCIGs using ray-based tomography, we in...

Three parallel space-decomposition minimization (PSDM) algorithms, based on the parallel variable transformation (PVT) and the parallel gradient distribution (PGD) algorithms (O.L. Mangasarian, SIMA Journal on Control and Optimization, vol. 33, no. 6, pp. 1916–1925.), are presented for solving convex or nonconvex unconstrained minimization problems. The PSDM algorithms decompose the variable sp...

In this paper, we present a method for computing angle-domain common-image gathers from wave-equation depth-migrated seismic images. We show that the method amounts to a radial-trace transform in the Fourier domain and that it is equivalent to a slant stack in the space domain. We obtain the angle-gathers using a stretch technique that enables us to impose smoothness through regularization. Sev...