Near-surface velocity gradients can be large enough to inhibit normal moveout corrections on a single pass of a complete shallow velocity function during routine shallow seismic reflection processing flows. Stretch artifacts that are the result of inversion and compression within the highest rate of velocity change portion of the shot gather can stack coherently on CMP sections. The constant ve...

The variation in seismic P to P reflection amplitude with offset (AVO) caused by a system of fractures embedded in an isotropic background is investigated. Additionally. a sensitivity analysis of AVO parameters with respect to the fracture system parameters is made. The fracture system is assumed to be aligned vertically or horizontally and can be gas filled or fluid filled. Elastic constants a...

This article addresses the question whether time-lapse seismic reflection techniques can be used to follow and quantify the effects of solution salt mining. Specifically, the production of magnesium salts as mined in the north of the Netherlands is considered. The use of seismic time-lapse techniques to follow such a production has not previously been investigated. For hydrocarbon production an...

We present a method for estimating seismic attenuation based on frequency shift data. In most natural materials, seismic attenuation increases with frequency. The high-frequency components of the seismic signal are attenuated more rapidly than the low-frequency components as waves propagate. As a result, the centroid of the signal’s spectrum experiences a downshift during propagation. Under the...

Existence of gas-hydrates in the marine sediments elevates the velocity of seismic waves, whereas even a small amount of underlying free-gas decreases the seismic velocity considerably. These changes in velocities can be used for the assessment of gas-hydrates. The traveltime inversion is an effective method to derive a 2-D velocity structure from the seismic data. We have applied the method to...

A method for automatic horizon tracking in reflection seismic data images across discontinuities is described. Horizon tracking is an important task of the structural interpretation of seismic images, however the automatic tracking across discontinuities has still not been solved satisfactorily. The reason for this is the difficulty involved in locating non-ambiguous local correlation features ...

Basis pursuit inversion of seismic reflection data for reflection coefficients is introduced as an alternative method of incorporating a priori information in a seismic inversion process. The inversion is accomplished by building a dictionary of functions, representing seismic reflection responses, and constituting the seismic trace as a superposition of these responses. Basis pursuit decomposi...

In reflection seismology, knowing the seismic wavelet is important both for processing seismic data and for modeling the seismic response. There are two approaches to obtain the seismic wavelet. One approach is deterministic and the other is statistic. This work belongs to the second category. A seismic wavelet is determined by the product of amplitude spectrum and phase spectrum. A conventiona...