Analysis of seafloor seismograms of the 2003 Tokachi-Oki earthquake sequence for earthquake early warning

View/ Open
Date
2008-07-31Author
McGuire, Jeffrey J.
Concept link
Simons, Frederik J.
Concept link
Collins, John A.
Concept link
Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/3362As published
https://doi.org/10.1029/2008GL033986DOI
10.1029/2008GL033986Keyword
Tokachi-Oki; Earthquake; WarningAbstract
Earthquake Early Warning (EEW) algorithms estimate the magnitude of an underway rupture from the first few seconds of the P-wave to allow hazard assessment and mitigation before the S-wave arrival. Many large subduction-zone earthquakes initiate 50–150 km offshore, potentially allowing seafloor instruments sufficient time to identify large ruptures before the S-waves reach land. We tested an EEW algorithm using accelerograms recorded offshore Hokkaido in the region of the 2003 Mw 8.1 Tokachi-Oki earthquake and its aftershocks. A wavelet transform of the first ∼4 s of the P-wave concentrates information about earthquake magnitude from both waveform amplitude and frequency content. We find that wavelets with support of a few seconds provide discriminants for EEW that are both accurate enough to be useful and superior to peak acceleration or peak velocity. Additionally, we observe a scaling of wavelet coefficient magnitude above Mw 6.0 indicating that, at least for the mainshock (Mw 8.1) and largest aftershock (Mw 7.1), the final size of a rupture could have been estimated from the initial portion of the seismogram.
Description
Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 35 (2008): L14310, doi:10.1029/2008GL033986.
Collections
Suggested Citation
Geophysical Research Letters 35 (2008): L14310Related items
Showing items related by title, author, creator and subject.
-
Post-seismic viscoelastic deformation and stress transfer after the 1960 M9.5 Valdivia, Chile earthquake : effects on the 2010 M8.8 Maule, Chile earthquake
Ding, Min; Lin, Jian (Oxford University Press, 2014-03-04)After the 1960 M9.5 Valdivia, Chile earthquake, three types of geodetic observations were made during four time periods at nearby locations. These post-seismic observations were previously explained by post-seismic afterslip ... -
Earthquake swarms on transform faults
Roland, Emily C.; McGuire, Jeffrey J. (John Wiley & Sons, 2009-06-04)Swarm-like earthquake sequences are commonly observed in a diverse range of geological settings including volcanic and geothermal regions as well as along transform plate boundaries. They typically lack a clear mainshock, ... -
Earthquake scaling relations for mid-ocean ridge transform faults
Boettcher, Margaret S.; Jordan, T. H. (American Geophysical Union, 2004-12-09)A mid-ocean ridge transform fault (RTF) of length L, slip rate V, and moment release rate dot above M can be characterized by a seismic coupling coefficient χ = A E/A T, where A E ∼ dot above M/V is an effective seismic ...