Accession Number:

ADA270125

Title:

Analysis of Regional Bodywave Phases from Earthquakes in Western China

Descriptive Note:

Final rept. 1 Aug 1991-1 Feb 1993

Corporate Author:

STATE UNIV OF NEW YORK AT BINGHAMTON DEPT OF GEOLOGICAL SCIENCE AND ENVIRONMENTAL STUDIES

Personal Author(s):

Report Date:

1993-06-17

Pagination or Media Count:

53.0

Abstract:

Broadband regional bodywave data have been collected and modeled for three profiles of earthquakes recorded at CDSN station WMQ in western China. The first profile is from earthquakes located to the southwest, within the Tienshan and Tarim basin. The second is from earthquakes to the NNE across the Altai mountains and the western tip of Mongolia and into Siberia. The third profile is from earthquakes to the SSE, some near the Lop Nor test site, and others from the Altyn Tagh and Qaidam Basin. Plane-layered velocity structure models were determined for each profile, and synthetic seismograms were computed using a frequency-wavenumber integration technique. For each earthquake, an appropriate source mechanism is assumed, and synthetic seismograms are computed for source depths of 10, 20 and 30 km. The modeling demonstrates that regional P sub n -P sub pg wavetrains result from the interference of several phases. Since some of these depart the source upward and other depart downward, this interference is sensitive to source depth and source mechanism. Therefore, as long as accurate synthetic seismograms can be computed, modeling these phases can serve as a powerful discriminant of earthquakes and explosions.

Subject Categories:

  • Seismology
  • Explosions

Distribution Statement:

APPROVED FOR PUBLIC RELEASE