Multiple Seismic Events
Semiannual technical rept. no. 4
WISCONSIN UNIV-MILWAUKEE DEPT OF GEOLOGICAL SCIENCES
Pagination or Media Count:
Spectral and correlation analyses were conducted with an earthquake and eight selected nuclear explosions, one known to be a double detonation, another known to be a single shot, and the rest of possible multiple sources. All these seismic events were fired or occurred at the Nevada Test Site. In this study, it was found that the elastic source dimension of the natural event was significantly larger than those corresponding to the nuclear explosions. Clear differences were also found to exist in the slope of the displacement spectra of the nuclear explosions and earthquake in the range of frequencies from .20 Hz to the corresponding peak frequency. This last result suggests a potential tool for the discrimination of seismic events. In an attempt to investigate the possibility of a multiple explosive nature for the remaining events, comparisons of theoretical modulation functions with the actual amplitude spectra of each event and with the amplitude spectrum ratios of the double event with the unknown events were conducted. Correlation analyses were applied to the four following cases cross-correlation of natural event with nuclear events, known single explosion with known double explosion, shots of unknown multiplicity with single detonation, and known double explosion with detonations of unknown multiplicity.
- Seismic Detection and Detectors