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pure and applied geophysics

, Volume 98, Issue 1, pp 40–48 | Cite as

A comparison of short-wave and long-wave velocities in layered media

  • Indra N. Gupta
Article
  • 52 Downloads

Summary

Ray theory based on Snell's law is strictly valid only when the variation of physical constants is small within a wavelength. In explosion seismology, Snell's law may apply to the arrival times of the ‘first breaks’, but not to those of the seismic ‘reflections’. For a stack of homogeneous, isotropic plane layers, the average velocity at its short-wavelength limit is greater than that at the long-wavelength limit for any given angle of incidence. Considering a few example of layered media, calculations are made for both short-wave and long-wave average velocities as a function of the angle of incidence. The former velocity shows a steady increase with the angle of incidence whereas the latter velocity may sometimes pass through a minimum before attaining its maximum value for horizontal propagation.

Keywords

Reflection Arrival Time Average Velocity Steady Increase Isotropic Plane 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Birkhäuser Verlag 1972

Authors and Affiliations

  • Indra N. Gupta
    • 1
  1. 1.Department of GeologyUniversity of KentuckyLexingtonUSA

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