Accession Number : ADA183828
Title : An Analysis of the Effects of Tectonic Release on Short-Period P Waves Observed from Shagan River Explosions.
Descriptive Note : Final rept. Sep 85-Sep 86,
Corporate Author : S-CUBED LA JOLLA CA
Personal Author(s) : Barker,Brian W ; Murphy,John R
Report Date : Feb 1987
Pagination or Media Count : 65
Abstract : Large samples of teleseismic P wave amplitude and waveform data recorded from Shagan River underground explosions have been collected and systematically analyzed in an attempt to identify any effects which may correlate with the amount of tectonic release accompanying these explosions. Results of these analyses indicate that these teleseismic P wave data do not provide any unambiguous evidence of effects of tectonic release in the short-period range of interest in m sub b determination. However, the results of a preliminary theoretical analysis indicate that such negative evidence is not definitive in that there are plausible models of tectonic release for which no detectable variations in the observed teleseismic P waveforms are theoretically expected to result from the superposition of these two sources. At the same time, such models of tectonic release predict significant positive bias in the network-averaged m sub b values for explosions accompanied by the mode of tectonic release traditionally associated with the Shagan River test site. Thus, the currently available seismic data do not exclude the possibility that tectonic release may be introducing a positive bias of as much as several tenths of a magnitude unit into the network-averaged m sub b values computed for some Shagan River explositons. Keywords: Explosion seismology; Threshold Test Ban Treaty; Network; USSR; Global Digital Seismic; Seismic body waves; Nuclear explosion detection; Radiation patterns.
Descriptors : *NUCLEAR EXPLOSION DETECTION , *VALIDATION , *SEISMIC DETECTION , *UNDERGROUND EXPLOSIONS , *TREATIES , AMPLITUDE , BIAS , LONG RANGE(DISTANCE) , MODELS , NUCLEAR EXPLOSION DETECTION , PRIMARY WAVES(SEISMIC WAVES) , RADIATION PATTERNS , SAMPLING , SEISMIC DATA , SEISMIC WAVES , SEISMOLOGY , SHORT RANGE(TIME) , TECTONICS , TEST FACILITIES , THEORY , THRESHOLD EFFECTS , TREATIES , UNDERGROUND EXPLOSIONS , USSR , WAVEFORMS , PRIMARY WAVES(SEISMIC WAVES) , DATA REDUCTION
Subject Categories : Seismic Detection and Detectors
Distribution Statement : APPROVED FOR PUBLIC RELEASE