Definition

Refraction Seismology - A program to map geologic structure by using head waves. Head waves involve energy that enters a high-velocity medium (refractor) near the critical angle and travels in the high-velocity medium nearly parallel to the refractor surface. Head wave arrivals are identified in terms of time after the shot and distance from the shot. The objective is to determine the arrival times of the head waves in order to map the depth to the refractors in which they traveled*.

Useful References

• Burger, H. R., Exploration Geophysics of the Shallow Subsurface, Prentice Hall P T R, 1992.
• Reynolds, J.M. An Introduction to Applied and Environmental Geophysics, Wiley, 1997.
• Telford, W. M., L. P. Geldart, and R. E. Sheriff, Applied Geophysics, 2nd ed., Cambridge University Press, 1990.
• Geosphere Seismic Page. This is a nice page that shows some examples of seismic reflection and refraction methods being used for near-surface applications.

*Definition from the Encyclopedic Dictionary of Exploration Geophysics by R. E. Sheriff, published by the Society of Exploration Geophysics.