Real-time magnitude proxies for earthquake early warning in Israel

Sadeh, Menahem; Ziv, A.; Wust-Bloch, Hillel

doi:10.1093/gji/ggt407

Cited by 13 publications

(13 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar differences leading to an underestimation of peak ground acceleration have also been shown by Campbell and Bozorgnia (2006), who compared ground-motion prediction equations (GMPEs) derived from global data and GMPEs, which were devised for Europe and the Middle East by Ambraseys et al (2005). Hereafter, we use the local magnitude scaling relation of Sadeh et al (2014) instead of the global relations derived by Kuyuk and Allen (2013a). The missed event, flagged as teleseismic by ElarmS, is not actually a teleseismic event.…”

Section: Playbacks Resultsmentioning

confidence: 52%

“…We find that it is necessary to use a regionally developed magnitude estimation equation to relate maximum displacement P d with magnitude. The magnitude relation previously derived from an independent dataset (Sadeh et al, 2014) is an excellent fit between catalog magnitudes and ElarmS results for historical data with 3 < M D ≤ 5:3 and for several available RT M D > 3 events. We note that data used here do not include large magnitude earthquakes and therefore using the adjusted magnitude relations should be done with care.…”

Section: Discussionmentioning

confidence: 57%

“…Instead, we examine a locally derived magnitude to P d relation using a set of 95 historical earthquakes between 2:5 ≤ M D ≤ 5:3 recorded by the GII between 2002 and 2011. Sadeh et al (2014) found a regional magnitude to P d relation for Israel: E Q -T A R G E T ; t e m p : i n t r a l i n k -; d f 3 ; 3 1 3 ; 1 0 2 3can be rewritten in the form of equation (2) as E Q -T A R G E T ; t e m p : i n t r a l i n k -; d f 4 ; 3 1 3 ; 7 3 3 M D 5:7935 0:96061log 10 P d log 10 R; 4 in which P d is now in centimeters.…”

Section: Playbacks Resultsmentioning

confidence: 99%

“…Event magnitudes are marked as open circles, stations magnitudes used for calculating the events magnitudes are marked as dots. (Top) Using P d -magnitude relations afterKuyuk and Allen (2013a) and (bottom) using P d -magnitude relations afterSadeh et al (2014).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Implementing the ElarmS Earthquake Early Warning Algorithm on the Israeli Seismic Network

Nof

Allen

2016

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

Earthquake early warning systems (EEWS) are being operated and tested increasingly around the globe in recent years. Following the Israeli government's decision to build an EEWS in Israel, and as the Californian EEWS (ShakeAlert) moves toward its operational phase, we demonstrate implementation of one of its three algorithms, ElarmS, to the Israel region. We provide new tools and approaches for implementing and assessing ElarmS outside of California. The main challenges of this research are to identify, verify, and adjust the embedded location-dependent parameters in ElarmS to the Israeli region, utilizing an unoptimized seismic network and low seismicity rate. To this end, we run ElarmS in three different modes: (1) historical playbacks, (2) real-time continuous data processing, and (3) simulated data playbacks. These modes enable us to overcome the limitations of low seismicity rates in the region and evaluate the performance of ElarmS with the network that is currently available. We use historical playbacks to adjust the magnitude estimation equations of ElarmS. We then analyze real-time processing results and provide detailed analysis of two significant events in the region (M D 5.5 and 4.4). Finally, we provide the first case of how to use synthetic data to evaluate the performance of ElarmS. We find that alert times are mostly affected by the network geometry and also by data delays. Alerts are typically issued within 80 ms after the arrival of the required four P-wave triggers data to the system. Magnitude estimations are reliable for events with M D > 3:5 within 100 km of the Israeli network using a locally adjusted magnitude relation equation.

show abstract

Section: Playbacks Resultsmentioning

confidence: 52%

Section: Discussionmentioning

confidence: 57%

Section: Playbacks Resultsmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Implementing the ElarmS Earthquake Early Warning Algorithm on the Israeli Seismic Network

Nof

Allen

2016

Bulletin of the Seismological Society of America

View full text Add to dashboard Cite

show abstract

“…Previous studies show that while the correlation of individual

τ_{p}^{\max}

or τ c with catalog magnitude is rather weak, that of event‐average is much stronger [ Allen and Kanamori , ; Brown et al , ; Lancieri et al , ; Sadeh et al , ]. Out of the 440 earthquakes analyzed in this study, 113 were recorded by four or more stations.…”

Section: The Log‐average Periodmentioning

confidence: 99%

New frequency‐based real‐time magnitude proxy for earthquake early warning

Ziv

2014

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

The two frequency‐based magnitude proxies currently employed by earthquake early warning systems in California are the predominant and the characteristic periods. These proxies, obtained using simple expressions that are valid for noise‐free monochromatic signals, yield erroneous result. The log‐average period, τlog, introduced in this study, is calculated directly from the actual velocity spectrum of the first few seconds of the seismic record. Using data from South California and Japan consisting of 440 earthquakes whose magnitudes range between 3 and 7.3, it is demonstrated that τlog is better correlated with the catalog magnitude than the predominant period and provides better magnitude assessment than the characteristic period for small magnitudes (M<4). The average prediction error is reduced with increasing the input interval up to 6 s. It appears that a single linear scaling describes the relation between log(τlog) and the catalog magnitude for the entire magnitude range studied here.

show abstract

Magnitude estimation and ground motion prediction to harness fiber optic distributed acoustic sensing for earthquake early warning

Lior

Rivet

Ampuero

et al. 2023

Sci Rep

View full text Add to dashboard Cite

Earthquake early warning (EEW) systems provide seconds to tens of seconds of warning time before potentially-damaging ground motions are felt. For optimal warning times, seismic sensors should be installed as close as possible to expected earthquake sources. However, while the most hazardous earthquakes on Earth occur underwater, most seismological stations are located on-land; precious seconds may go by before these earthquakes are detected. In this work, we harness available optical fiber infrastructure for EEW using the novel approach of distributed acoustic sensing (DAS). DAS strain measurements of earthquakes from different regions are converted to ground motions using a real-time slant-stack approach, magnitudes are estimated using a theoretical earthquake source model, and ground shaking intensities are predicted via ground motion prediction equations. The results demonstrate the potential of DAS-based EEW and the significant time-gains that can be achieved compared to the use of standard sensors, in particular for offshore earthquakes.

show abstract

Real-time magnitude proxies for earthquake early warning in Israel

Cited by 13 publications

References 33 publications

Implementing the ElarmS Earthquake Early Warning Algorithm on the Israeli Seismic Network

Implementing the ElarmS Earthquake Early Warning Algorithm on the Israeli Seismic Network

New frequency‐based real‐time magnitude proxy for earthquake early warning

Magnitude estimation and ground motion prediction to harness fiber optic distributed acoustic sensing for earthquake early warning

Contact Info

Product

Resources

About