Analysis of seafloor seismograms of the 2003 Tokachi-Oki earthquake sequence for earthquake early warning
McGuire, Jeffrey J.
Simons, Frederik J.
Collins, John A.
MetadataShow full item record
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.
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.
Suggested CitationGeophysical Research Letters 35 (2008): L14310
Showing items related by title, author, creator and subject.
Llenos, Andrea L. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2010-06)Large earthquake rupture and triggering mechanisms that drive seismicity in subduction zones are investigated in this thesis using a combination of earthquake observations, statistical and physical modeling. A comparison ...
Spatial and temporal variations in earthquake stress drop on Gofar Transform Fault, East Pacific Rise : implications for fault strength Moyer, Pamela A.; Boettcher, Margaret S.; McGuire, Jeffrey J.; Collins, John A. (John Wiley & Sons, 2018-09-07)On Gofar Transform Fault on the East Pacific Rise, the largest earthquakes (6.0 ≤ MW ≤ 6.2) have repeatedly ruptured the same portion of the fault, while intervening fault segments host swarms of microearthquakes. These ...
Stress triggering in thrust and subduction earthquakes and stress interaction between the southern San Andreas and nearby thrust and strike-slip faults Lin, Jian; Stein, Ross S. (American Geophysical Union, 2004-02-03)We argue that key features of thrust earthquake triggering, inhibition, and clustering can be explained by Coulomb stress changes, which we illustrate by a suite of representative models and by detailed examples. Whereas ...