Estimates of Ground Motion at Minuteman Missile Sites from Two Large 1979 Earthquakes.
Abstract
The ground motion caused by the February 28, 1979, St. Elias, Alaska, and March 14, 1979, Petatlan, Mexico, earthquakes is estimated at the MINUTEMAN missile sites in the central United States. The estimates are made by obtaining recordings of the ground motion at other locations in the United States and correcting these recordings to be appropriate for the ranges and azimuths of the MINUTEMAN installations. The ground motion from the two earthquakes was very large (Ms approx. 8.0) in the central United States and most recordings were off-scale. The most useful records were from Wood-Anderson seismometers, especially from two stations in Utah. The dominant motion is due to surface waves with periods of 10 to 20 seconds. Theoretical considerations supported by teleseismic observations of these events and central United States observations of some large aftershocks suggest that the range and azimuth differences between the Utah Wood-Anderson seismometers and the MINUTEMAN sites do not have a strong effect on the ground motions. Comparing recorded motions from several seismometers in the western United States, we also obtain some idea of the possible effect of local structure variations. The ground motion estimates are presented in the form of standard five percent damped response spectra. At three seconds the response spectra are about the same (within a factor of two or three) at all the MINUTEMAN sites.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1980
- Accession Number
- ADA095365
Entities
People
- J. L. Stevens
- T. C. Bache
Organizations
- Utility Systems Science and Software (United States)