Numerical and Physical Modeling of Diffraction
In Chapter 3, the forward problem is presented in a collection of papers which focus on numerical and physical modeling. Whereas the preceding chapter contains a number of numerical modeling studies, the topic of this chapter is the zero-offset and prestack seismic diffraction responses of simple structural and stratigraphic features. The convolutional model of seismic diffraction is another key theme. Whereas geophysicists undoubtedly have good knowledge of the convolutional model of seismic reflection, the convolutional model for seismic diffraction, and the common basis of both convolutional models in the Kirchhoff integral, is probably less well known.
A method for computing certain types of diffracted rays and corresponding travel-time curves in laterally inhomogeneous media with slightly curved interfaces is suggested. Numerical examples are presented.
Figures & Tables
The use of diffraction imaging to complement the seismic reflection method is rapidly gaining momentum in the oil and gas industry. As the industry moves toward exploiting smaller and more complex conventional reservoirs and extensive new unconventional resource plays, the application of the seismic diffraction method to image sub-wavelength features such as small-scale faults, fractures and stratigraphic pinchouts is expected to increase dramatically over the next few years. “Seismic Diffraction” covers seismic diffraction theory, modeling, observation, and imaging. Papers and discussion include an overview of seismic diffractions, including classic papers which introduced the potential of diffraction phenomena in seismic processing; papers on the forward modeling of seismic diffractions, with an emphasis on the theoretical principles; papers which describe techniques for diffraction mathematical modeling as well as laboratory experiments for the physical modeling of diffractions; key papers dealing with the observation of seismic diffractions, in near-surface-, reservoir-, as well as crustal studies; and key papers on diffraction imaging.