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Title: Regional seismic event identification and improved locations with small arrays and networks. Final report, 7 May 1993-30 September 1995

Abstract

This final report contains a summary of our work on the use of seismic networks and arrays to improve locations and identify small seismic event. We have developed techniques to migrate 3-component array records of local, regional and teleseismic wavetrains to directly image buried two- and three-dimensional heterogeneities (e.g. layer irregularities, volumetric heterogeneities) in the vicinity of the array. We have developed a technique to empirically characterize local and regional seismic code by binning and stacking network recordings of dense aftershock sequences. The principle motivation for this work was to look for robust coda phases dependent on source depth. We have extended our ripple-fired event discriminant (based on the time-independence of coda produced by ripple firing) by looking for an independence of the coda from the recording direction (also indicative of ripple-firing).

Authors:
; ;
Publication Date:
Research Org.:
Scripps Institution of Oceanography, La Jolla, CA (United States)
OSTI Identifier:
273142
Report Number(s):
AD-A-305683/5/XAB
CNN: Contract F19628-93-K-0021; TRN: 62120036
Resource Type:
Technical Report
Resource Relation:
Other Information: DN: Original contains color plates: All DTIC/NTIS reproductions will be in black and white; PBD: 20 Sep 1995
Country of Publication:
United States
Language:
English
Subject:
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE; 35 ARMS CONTROL; NUCLEAR EXPLOSION DETECTION; SEISMIC SURVEYS; SEISMIC ARRAYS; REGIONAL ANALYSIS; ARMS CONTROL; VERIFICATION; PROGRESS REPORT

Citation Formats

Vernon, F.L., Minster, J.B., and Orcutt, J.A. Regional seismic event identification and improved locations with small arrays and networks. Final report, 7 May 1993-30 September 1995. United States: N. p., 1995. Web.
Vernon, F.L., Minster, J.B., & Orcutt, J.A. Regional seismic event identification and improved locations with small arrays and networks. Final report, 7 May 1993-30 September 1995. United States.
Vernon, F.L., Minster, J.B., and Orcutt, J.A. 1995. "Regional seismic event identification and improved locations with small arrays and networks. Final report, 7 May 1993-30 September 1995". United States. doi:.
@article{osti_273142,
title = {Regional seismic event identification and improved locations with small arrays and networks. Final report, 7 May 1993-30 September 1995},
author = {Vernon, F.L. and Minster, J.B. and Orcutt, J.A.},
abstractNote = {This final report contains a summary of our work on the use of seismic networks and arrays to improve locations and identify small seismic event. We have developed techniques to migrate 3-component array records of local, regional and teleseismic wavetrains to directly image buried two- and three-dimensional heterogeneities (e.g. layer irregularities, volumetric heterogeneities) in the vicinity of the array. We have developed a technique to empirically characterize local and regional seismic code by binning and stacking network recordings of dense aftershock sequences. The principle motivation for this work was to look for robust coda phases dependent on source depth. We have extended our ripple-fired event discriminant (based on the time-independence of coda produced by ripple firing) by looking for an independence of the coda from the recording direction (also indicative of ripple-firing).},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1995,
month = 9
}

Technical Report:
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  • Only very limited experience exists for regional seismic signals from small or decoupled nuclear explosions, which would be important in a CTBT monitoring environment. The goal of this research has been to enhance the experience base for such events at the prototype International Data Center (IDC) and to identify potential techniques and limitations of IDC seismic monitoring at the low magnitude levels appropriate to a CTBT. To accomplish this objective theoretical source scaling was used to scale the original records observed from underground nuclear explosions down to the levels appropriate to CTBT monitoring goals (e.g. 1 kt fully decoupled), andmore » the scaled signals were reembedded into normal background noise conditions. We then analyzed the simulated records in the time and frequency domains to assess their implications for detection, location, and identification The regional signal characteristics for the scaled explosions can then be compared to similar behavior in signals from small events of other source types In a separate study under this contract, we also investigated regional seismic identification techniques for some specific events recently detected by the IDC.« less
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