Reverse-time migration is a two-way time-domain finite-frequency technique that accurately handles the propagation of complex scattered waves and produces a band-limited representation of the subsurface structure that is conventionally assumed to be linear in the model parameters. Because of this underlying linear single-scattering assumption, most implementations of this method do not satisfy ...

Zhdanov, M.S. and Tjan, T., 1994. Migration by analytic continuation through a variable background medium. Journal of Seismic Exploration, 3: 283-297. Conventional migration of wavefields is based on depth extrapolation of the upgoing field in reverse time. This extrapolation provides us with a means to determine the positions of reflectors and diffraction points and, therefore, to produce an i...

We apply iterative resolution estimation to least-squares Kirchhoff migration. Resolution plots reveal low illumination areas on seismic images and provide information about image uncertainties.

The objective of this work is to build an efficient algorithm (a) to estimate seismic velocity from time-migration velocity, and (b) to convert time-migrated images to depth. We establish theoretical relations between the time-migration velocity and the seismic velocity in 1 Page 1 of 23 GEOPHYSICS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 3...

We address the problem of estimating seismic velocities inside the Earth which is necessary for obtaining seismic images in regular Cartesian coordinates. The main goals are to develop algorithms to convert time-migration velocities to true seismic velocities, and to convert time-migrated images to depth images in regular Cartesian coordinates. Our main results are three-fold. First, we establi...

A key to reducing the risks and costs of associated with oil and gas exploration is the fast, accurate imaging of complex geologies, such as salt domes in the Gulf of Mexico and overthrust regions in U.S. onshore regions. Prestack depth migration generally yields the most accurate images, and one approach to this is to solve the scalar wave equation using nite diierences. Current industry compu...

Provided the velocity of the medium is known and the the medium does not allow different reflectors to have identical surface seismic measurements that persist under small perturbations of the medium, map migration achieves a one-to-one mapping from surface seismic data to the subsurface seismic image by using the slopes in addition to the location (and time) of the events in the data. In this ...

Migration in the angle domain creates seismic images for different reflection angles. We present a method for computing angle-domain common-image gathers from seismic images obtained by depth migration using wavefield continuation. Our method operates on prestack migrated images and produces the output as a function of the reflection angle, not as a function of offset ray parameter as in other ...

One of the most common and challenging problems in seismology is the prediction of source-receiver paths taken by seismic energy in the presence of lateral variations in wavespeed. The solution to this problem is required in many applications that exploit the high frequency component of seismic records, such as body wave tomography, migration of reflection data and earthquake relocation. The pr...

Land multicomponent seismic has garnered significant attention and demonstrated substantial growth in the last five years. The bulk of this growth in multicomponent activity has been in western Canada. While multicomponent seismic has been around for many years, historical cost and quality concerns have limited its use as a routine exploration tool. The current resurgence of multicomponent seis...