Variability of Seismic Waveforms Recorded at LASA from Small Subregions of Kamchatka.

• Main Authors: Blandford,R., Clark,D.
• Other Authors: TELEDYNE GEOTECH ALEXANDRIA VA SEISMIC DATA ANALYSIS CENTER
• Format: Text
• Language: English
• Published: 1975
• Subjects: Seismology; Seismic Detection and Detectors; *SEISMIC DETECTION; *KAMCHATKA PENINSULA; DATA PROCESSING; USSR; NUCLEAR EXPLOSIONS; UNDERGROUND EXPLOSIONS; FAULTS(GEOLOGY); SEISMIC DATA; TABLES(DATA); MAPS; EARTHQUAKES; EPICENTERS; CORRELATION TECHNIQUES; SEISMOLOGICAL STATIONS; SEISMOMETERS; Vela Uniform; Large aperture seismic array; *Seismic discrimination; Short period seismometers; Kamchatka Peninsula; Kamchatka
• Online Access: http://www.dtic.mil/docs/citations/ADA028968; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA028968

A comparison of LASA short-period waveforms from earthquakes in three 1 degree diameter circles on capes of Kamchatka reveals substantial differences in the typical waveform from each circle, and both simple and complex events within each circle. A total of 65 events was examined. Only a few events, all from one region have emergent waveforms which Kolar and Pruvost (1975) have suggested to be required for successful simulation of an earthquake by an array of explosions. Several events were found with M(s) only slightly greater than m(b) - 1.5, the region of the M(s):m(b) plane typical of explosions. The low values of M(s)-m(b) and compressive first motions at LASA, together with published fault plane solutions from the area suggest that those events are from 45 degree thrust faults. Defining m(b) on the maximum amplitude in the first 10 seconds of the short-period signal would be a useful shot array countermeasure.