Experimental evidence to support the double head wave method of generating a rare faction first motion [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 1959.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- 7 pages : digital, PDF file
- Additional Creators:
- Lawrence Livermore National Laboratory
United States. Department of Energy
United States. Department of Energy. Office of Scientific and Technical Information
- An earlier report suggested a double headwave method of generating a rarefaction first motion. In this method a geologic situation is selected so that energy that has been critically refracted once above the shot and once below shot arrives first. Since the theory of headwaves gives in the usual stationary phase approximation a ninety degree phase shift for each critical refraction, energy that has been critically refracted twice produces a 180 degree phase shift. Oil well data was presented to show that the necessary geologic situation exists in nature. A question has come up regarding the propagation of long wave lengths (16,000 ft) in the thin bed (3000 ft.) above the shot in the geologic situation cited in the earlier report. At the tine of writing of the report it was realized that the thickness of the bed should be considered in propagating the 3 to 5 wavelengths along the bed. The theoretical problem of propagation in high speed elastic bed has not been solved. The best information available at this time indicates that it might indeed be possible to go out into reef country and experimentally find a location suitable to generate a rarefaction first motion by the double head wave method. As in the earlier report this scheme is offered only as a second method that could fool a set of rules regarding first notions.
- Published through SciTech Connect.
Werth, G. C.
- Funding Information:
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