Transmission caustics cause velocity estimation techniques based based on straightforward analysis of image volume moveout to fail. For example the diierential semblance objective function (a quantitative measure of image volume moveout) is smooth and has only kinemat-ically correct critical points when the incident waveeeld is free of caustics, but loses these properties when caustics are pres...

the application of traditional nmo-correction techniques in the processing of seismic data may result in severe distortion. this distortion is observed as a decrease in frequency content (nmo stretch). this may be seen as the source of problems in the processing with stretch. in this paper, cnmo method is applied which doesn't have the `stretching effects' of conventional nmo correcti...

Oil, gas, and geothermal reservoirs, and overlying strata are often composed of anisotropic rocks. Proper treatment of anisotropy during the processing of seismic data not only helps to avoid distortions in reservoir imaging, but also provides estimates of the anisotropic coefficients, which carry valuable information about lithology and fracture networks. Accurate estimation of the velocity mo...

There is renewed interest in velocity anisotropy, and publications of researchers outside SEP describe various schemes for estimating anisotropic moveout from seismic data. However, those schemes often face problems in that they commit too early to a particular class of elastic models which may require auxiliary information not available from surface seismic data. In essence, they are model-dri...

Time migration velocity analysis can be performed by velocity continuation, an incremental process that transforms migrated seismic sections according to changes in the migration velocity. Velocity continuation enhances residual normal moveout correction by properly taking into account both vertical and lateral movements of events on seismic images. Finite-difference and spectral algorithms pro...

Conventional velocity analysis applied to images produced by wave-equation migration with a crosscorrelation imaging condition uses moveout information from space lags or focusing information from time lag. However, more robust velocity-estimation methods can be designed to simultaneously take advantage of the semblance and focusing information provided by migrated images. Such a velocity estim...

Conventional velocity analysis applied to images produced by wave-equation migration with a cross-correlation imaging condition makes use either of moveout information from space-lags or of focusing information from time-lags. However, more robust velocity estimation methods can be designed to take advantage simultaneously of the moveout and focusing information provided by the migrated images....

P waves from regional-distance earthquakes are complex and reverberatory, as would be expected from a combination of head waves, post-critical crustal reflections and shallow-incident P waves from the upper mantle. Although designed for steeply-incident teleseismic P waves, receiver functions (RFs) can also retrieve information about crustal structure from regional P. Using a new computation me...

Moveout analysis of long-spread P-wave data is widely used to estimate the key time-processing parameter η in layered VTI (transversely isotropic with a vertical symmetry axis) media. Inversion for interval η values, however, suffers from instability caused by the tradeoff between the effective moveout parameters and by the subsequent error amplification during Dix-type layer stripping. Here, w...