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Evaluation of Seismicity at U.S. Reservoirs.
Daly, W.; Judd, W.; Meade, R.
National Science Foundation, Washington, D.C. Research Applied to National Needs., May 1977, 31 p.
This paper summarizes the current state of knowledge regarding reservoir-associated seismicity, and evaluates the results of the survey of seismicity at large dams in the United States. All investigators emphasize the importance of regional geology and the state of stress in the earth. Geologic factors to be considered include rock type; nature of bedding planes, joints, and faults; and physical, mechanical, and chemical properties of the rock mass. The seismicity reported in the survey does not equal or exceed the predicted seismicity. The probability that a dam with a large reservoir will induce significant seismic activity can be estimated as P=20/3300=approx. .006. The probability of inducing a destructive earthquake is even less. The authors conclude that for a potentially destructive earthquake to be initiated near a reservoir, a unique combination of circumstances must be present and the probability of such combinations existing must be very low.
Ground motion; Dams; Pore pressure; Earthquake engineering; Reservoir engineering; Earthquakes; Reservoirs; Site surveys; Earth movements; Geological faults