Assessment of Infrasound Detection Capabilities in the Western US Using a Combination of Infrasound Arrays and Single Seismometers
Abstract
Ground truth sources can be useful for documenting how infrasound observations are affected by atmospheric conditions as well as testing predictive capabilities of the atmospheric model. To assess these issues, we focus on the infrasound analysis using a hybrid of regional scale seismic stations and infrasound arrays in the western US. The station distributions vary in time when USArray Transportable Array (TA) and local seismic network were installed. A total of 56 ground truth events were collected from static rocket motor burn tests (long duration up to 3 minutes) and rocket body demolitions (impulsive signals) in Utah from 2003 to 2013. In order to review hundreds of stations for individual events, automated infrasound detection and association techniques were developed. The detection procedure is based on STA/LTA trigger in combinations with spectral and amplitude analyses. Detected signals were subsequently associated using the closest three stations with estimates of phase velocity and azimuth used to refine the detections. The automatic detections indicate that infrasound signals from both types of sources are observed to distances of 600 km with some observed beyond 700 km. Infrasound arrival predictions using ground-to-space (G2S) atmospheric specifications compare well with both automatic and analysts infrasound picks including celerity and amplitude documenting seasonal variations in atmospheric conditions. The average detection percentages are 28.8 % and 24.7 % for rocket demolition and burn test datasets, respectively, twice as high as those produced by the analyst. Additional work is needed to quantify the effects of station distribution, atmospheric conditions, source coupling, acoustic to seismic coupling at seismometers, local noise levels and effectiveness of network processing on the proposed automated procedures.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.S11C2466P
- Keywords:
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- 7219 Seismic monitoring and test-ban treaty verification;
- SEISMOLOGYDE: 7294 Seismic instruments and networks;
- SEISMOLOGYDE: 7299 General or miscellaneous;
- SEISMOLOGY