It is common in shallow seismic studies for the compressional-wave velocity in unconsolidated sediments to increase by a factor of four or more at the transition from dry or partial water saturation to full saturation. Under these conditions, conventional NMO velocity analysis fails and leads to large depth and layer thickness estimates if the Dix equation is assumed valid. Prestack depth migra...

Acquisition and processing of multifold groundpenetrating radar (GPR) data enable detailed measurements of lateral velocity variability. The velocities constrain interpretation of subsurface materials and lead to significant improvement in image accuracy when coupled with prestack depth migration (PSDM). Reflection tomography in the postmigration domain was introduced in the early 1990s for vel...

When accompanied by the appropriate algorithmic approach, seismic imaging is an application that can take advantage of massively parallel computer systems. Three-dimensional (3D) prestack time migration (PSTM) and pre-stack depth migration (PSDM) are key components of seismic imaging and require very large computing resources. In this paper, we show that execution of these algorithms can be dra...

Abstract. 3D prestack depth migration is an important and commonly used way to obtain the images of complex structures in seismic date processing. In this paper, 3D prestack depth migration with hybrid four-way splitting scheme is investigated. Wavefield extrapolation is based on the 3D acoustic one-way. The hybrid four-way splitting algorithm based on factorization is derived. Numerical calcul...

The application of the pre-stack depth migration (PSDM) method using deep seismic reflection data is still a challenge. In this paper, dataset collected from Bohai Bay Basin used to test applicability method. After improving signal-to-noise ratio prestack gathers and building an accurate velocity model capturing lateral vertical variations, high-quality profile obtained. This shows detailed cru...

Reliable seismic depth migrations require an accurate input velocity model. Inaccurate velocity estimates will distort point diffractors into smiles or frowns on a depth section. For both poststack and prestack migrated sections, high velocities cause deep smiles while low velocities cause shallow frowns on migrated gathers. However, for prestack images in the offset domain, high velocities cau...