DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click
HERE to register or log in.
Accession Number:
ADA516184
Title:
Extension of Ms(VMAX) to Global Paths
Descriptive Note:
Conference paper
Corporate Author:
QUANTUM TECHNOLOGY SERVICES INC COCOA BEACH FL
Report Date:
2008-09-01
Pagination or Media Count:
8.0
Abstract:
Recent work with a prototype application for variable-period Rayleigh-wave magnitudes Russell, 2006 has reported use of the MsVMAX technique for periods between 8 and 25 seconds Bonner et al., 2006a, 2006b, 2007. More recently, the technique has been extended to 40 seconds Bonner, 2007. In all previous studies, the data were limited to continental paths and thoroughly reviewed. This study has attempted to evaluate an operational scenario whereby all surface-wave paths are considered. Two groups of data have been utilized, twenty-seven 27 shallow events from the Asian continent and a larger 143 events global event group with a broader depth range. All events have been reviewed by an analyst for validity. To obtain a better understanding of period and path effects, the data have been subdivided into three period ranges 8 - 17 seconds, 17 - 25 seconds, and 25 - 40 seconds and separated by predicted group slowness into oceanic paths slow 32.25 secdeg, continental paths slow 38.0 secdeg, and mixed oceanic-continental paths 32.25 secdeg less-than-or-equal-to slow less-than-or-equal-to 38.0 secdeg. Past studies have demonstrated the MsVMAX technique works well for continental paths between 8 and 25 seconds Bonner et al., 2006b, 2007. This study shows stable results for all paths oceanic, mixed, and continental between 8 and 25 seconds. Since the data have been shown to be path independent, the MsVMAX technique may provide an automated replacement for Ms, allowing the inclusion of regional stations with Airy phases and reducing the analyst burden.
Distribution Statement:
APPROVED FOR PUBLIC RELEASE
