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...

I show that, by estimating local event slopes in prestack seismic reflection data, it is possible to accomplish all common time-domain imaging tasks, from normal moveout to prestack time migration, without the need to estimate seismic velocities or any other attributes. Local slopes contain complete information about the reflection geometry. Once they are estimated, seismic velocities and all o...

Shot-geophone migration, commonly accomplished using wavefield depth extrapolation (“survey sinking”), has a two way reverse time realization as well. The reverse time version permits imaging of overturned reflections. Shot-geophone migration differs from other prestack migrations in the definition of the prestack image volume which it creates. This difference is most clearly seen by identifyin...

Prestack migration algorithms are usually divided into two classes: ray-tracing based migration methods and wave-equation methods. The latter methods provide more accurate migration images, especially in complex geological areas, but they are the relatively expensive compared with ray-based migration methods. In this work, I test the phase encoding strategy on three types of one-way wave equati...

An undersampled acquisition geometry and a limited recording aperture often produces migration noise (i.e., acquisition footprint) that blurs the subsurface reflectivity image. Here, we develop a prestack migration deconvolution (MD) filter that deblurs the migration image. The MD filter is applied to 3-D prestack SEG/EAGE salt data as well as 3-D marine data from Alaska. Results show that MD c...

In areas with structurally complex geology, tomographic velocity analysis is required to estimate velocities. This paper describes a tomographic velocity analysis algorithm which uses planewave synthesis imaging as a prestack migration. In reflection tomography, prestack migration is required for both event picking and traveltime error computation. Traveltime errors are often measured in the fo...

Constructing the seismic image in vertical time, as opposed to depth, eliminates the inherent ambiguity of resolving the vertical P -wave velocity from surface seismic data in transversely isotropic media with a vertical axis of symmetry (VTI media). By ray tracing in the space-time (x-τ)-domain, a traveltime map is built by interpolating the traveltime information along the rays onto a regular...