Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (9) Citing Articles via Google Scholar Google Scholar Articles by Nakahara, H. Articles by Hamaguchi, H. Search for Related Content GeoRef GeoRef Citation

Broadband Source Process of the 1998 Iwate Prefecture, Japan, Earthquake as Revealed from Inversion Analyses of Seismic Waveforms and Envelopes

Department of Geophysics
Graduate School of Science
Tohoku University
Sendai, Japan
(H.N, T.N., H.S., M.O.)
National Research Institute for Earth Science and Disaster Prevention
Tsukuba, Ibaraki, Japan
(S.K.)
Research Center for Prediction of Earthquakes and Volcanic Eruptions
Graduate School of Science
Tohoku University
Sendai, Japan
(H.H.)

Manuscript received 21 April 2001.

An earthquake of M 6.1 occurred on 3 September 1998, along an active fault at the southwestern foot of Mt. Iwate, a volcano in northeastern Japan. Acceleration records of this earthquake were obtained at seven stations within 40 km of the epicenter. In order to investigate the source process of this earthquake in a broad frequency range, we simultaneously conducted inversion analyses of low-frequency seismic waveforms and high-frequency seismogram envelopes. First, executing the envelope inversion by using the envelope Green function derived from the radiative-transfer theory in the high-frequency band of 2-16 Hz, we estimated the spatial distribution of seismic-wave energy radiation on the fault plane of 10 km x 10 km. We found that seismic-wave energy was strongly radiated from the southwestern deeper part of the fault plane. By using data from the same stations and using the same fault geometry as the high-frequency analysis, we applied a waveform-inversion method to three-component displacement records in the low-frequency band of 0.1-0.33 Hz. This result showed that seismic moment was mainly released at the shallow part of the fault. Comparing these results, we found that high-frequency energy was strongly radiated from the deepest periphery of the region, where seismic moment was mainly released. This result implies that the radiation of high-frequency energy was associated with the arrest of rupture for this earthquake.

This article has been cited by other articles:

				N. Pulido and L. A. Dalguer Estimation of the High-Frequency Radiation of the 2000 Tottori (Japan) Earthquake Based on a Dynamic Model of Fault Rupture: Application to the Strong Ground Motion Simulation Bulletin of the Seismological Society of America, August 1, 2009; 99(4): 2305 - 2322. [Abstract] [Full Text] [PDF]

				N. Kato How Frictional Properties Lead to Either Rupture-Front Focusing or Cracklike Behavior Bulletin of the Seismological Society of America, December 1, 2007; 97(6): 2182 - 2189. [Abstract] [Full Text] [PDF]

				Source Parameters and Rupture Velocities of Microearthquakes in Western Nagano, Japan, Determined Using Stopping Phases Bulletin of the Seismological Society of America, October 1, 2004; 94(5): 1762 - 1780.

				Source Characterization for Broadband Ground-Motion Simulation: Kinematic Heterogeneous Source Model and Strong Motion Generation Area Bulletin of the Seismological Society of America, December 1, 2003; 93(6): 2531 - 2545.