Source process of the 3 November 2002 Denali fault earthquake (central Alaska) from teleseismic observations

Arda A. Ozacar, Susan L. Beck, Douglas H. Christensen

Research output: Contribution to journalArticle

19 Scopus citations

Abstract

The November 3, 2002 Denali fault earthquake, which is the largest inland event ever recorded in central Alaska, occurred along an arcuate segment of the right-lateral strike-slip Denali fault. We use first-motion P wave polarities and inversions of teleseismic P waveforms for a fixed focal mechanism to constrain the rupture process. We find clear evidence for a substantial reverse component near the hypocenter at the beginning of the rupture. Twenty-five seconds later, rupture propagated unilaterally to the east on a strike-slip fault and released most of the seismic moment along an asperity located 170 km east of the hypocenter with a maximum slip of 8 m. This earthquake had a duration of ∼120 s and ruptured more than 300 km in length. Correlation with gravity anomalies suggests a relation between moment distribution and physical properties of subsurface rock units that may support a weaker middle fault segment marked by fewer aftershocks.

Original languageEnglish (US)
Pages (from-to)40-1 - 40-4
JournalGeophysical Research Letters
Volume30
Issue number12
DOIs
StatePublished - Jun 15 2003

    Fingerprint

Keywords

  • Body-wave inversion
  • Denali fault
  • Strike-slip earthquake

ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

Cite this