SCEC4 science plans emphasize the development and use of time-dependent seismic hazard analysis. SCEC is working to extend time-dependent seismic hazard analysis through application of EEW technologies.
Earthquake early warning (EEW) is a technology that can provide rapid information about an earthquake. Under favorable circumstances, EEW technology can provide automated warning of strong ground motions from an earthquake before those ground motions have propagated to all affected sites. EEW technology provides warnings after the earthquake has begun but before the earthquake has affected all users.
SCEC is working with the [http://www.cisn.org California Integrated Seismic Network (CISN)] in the development and evaluation of a prototype CISN EEW system.
== CISN EEW Testing System Development ==
== EEW Technology Description ==
SCEC is working to developed automated CISN EEW performance evaluation system. This system, currently called the CISN Testing Center (CTC), is based on the testing framework developed on the SCEC CSEP project.
== Example Observations from ShakeMap RSS for Event (M5.0 ) ==
EEW forecast capabilities require (a) ground motion (or other) geophysical sensors, (b) scientific processing software, and (c) a communication system distributing information to users. Detailed descriptions of EEW technology can be found here:
[[File:scec.eew.EEWTest.eewTest_SHAKEMAP-Test_Event10736069.png|340px|thumb|left|Fig 1: Plotting of ShakeMap observation data for Event in Southern California.]]
*[http://en.wikipedia.org/wiki/Earthquake_Early_Warning_%28Japan%29 Japan EEW]
[[File:scec.eew.EEWTest.eewTest_SHAKEMAP-Test_ZoomEvent10736069.png|340px|thumb|right|Fig 2: Plotting of ShakeMap observation data for Event in Southern California.]]
== CISN EEW Project ==
== Authorized Data Source ==
The ShakeMap authorized data source may provide the observational data used to validate short term ground motion forecasts.
[http://www.cisn.org California Integrated Seismic Network (CISN)] research groups, together with SCEC and USGS, are developing a prototype CISN EEW system called the CISN [http://earthquake.usgs.gov/earthquakes/ ShakeAlert] system.
[[SCEC]]'s current research focus on the [[ShakeAlert]] project is the development of an automated CISN EEW performance evaluation system. This EEW performance evaluation system, currently called the CISN Testing Center (CTC), is based on the testing framework developed on the SCEC [[CSEP]] project.
SCEC4 science plans emphasize the development and use of time-dependent seismic hazard analysis. SCEC earthquake system science research approach seeks to integrate EEW technologies into time-dependent seismic hazard analysis through applications.
CISN and SCEC are collaborating on the development of EEW evaluation tools and techniques. Detailed EEW development notes and current evaluation results are posted on related wiki entries including:
2010/09/30 08:37:35.93 37.1385 -117.3803 8.47 4.42 ML 24 144 21 0.23 NN 317359
2010/10/05 21:22:46.52 37.1526 -117.3758 9.21 4.14 ML 13 164 19 0.12 NN 318065
== Earthquake Wave Travel Time Curves ==
[[File:Define_Reference_Events.png|340px|thumb|right|Fig 5: Travel time curves show region for which no warnings are possible because of travel time and processing delays.]]
== Ground Motion Intensity Scale ==
[[File:shakemap_color_scale.png|340px|thumb|right|Fig 6: ShakeMap color scale shows instrumental intensity estimates or observations.]]
Testing Regional-scale Ground Motion Estimates for the CISN ShakeAlert Project
Philip Maechling, Maria Liukis, Thomas H. Jordan
Our SCEC research team has developed initial capabilities of the CISN Testing Center (CTC) as a part of the USGS-funded CISN ShakeAlert Project. The CTC is designed to compare regional-scale ground motion estimates, such as peak ground motion estimates, against observed ground motion data, for significant California Earthquakes. The CTC is designed to identify which ShakeAlert ground motion estimation methods produce the best fit to observed ground motions.
Scientific goals of the CTC include (a) development of consensus among SCEC researchers on meaningful measures of comparison between ground motion estimates and observations, (b) collection and analysis of ShakeAlert performance information, and (c) integration of standard Probabilistic Seismic Hazard Analysis (PSHA) terms and practices into EEW. The technical goal of the CTC is to develop an automated system that can comparing ground motion estimates against ground motion observations. The CTC system used the CSEP testing framework to automate the evaluation of CISN ShakeAlert rapid earthquake parameters including ground motion forecasts for each event.
As part of this year’s CTC development, we updated the CSEP Testing Framework to use the USGS ShakeMap RSS Feed as an authorized source of event-based ground motion observations. As ShakeAlert systems produces rapid ground motion estimates for significant California events, the CTC will evaluate those ShakeAlert ground motion estimates against CISN ground motion observation using goodness-of-fit algorithms defined by CISN scientific groups.
Our ShakeAlert ground motion forecast testing shares scientific and technical goals with several other SCEC activities including validation of attenuation relationships, synthetic ShakeMaps, velocity model and wave propagation model goodness of fit measures, and short term ground motion forecast testing. The CTC system is designed to support CISN ShakeAlert testing and to also be applicable for evaluation of other ground motion estimation methods.
*[http://earthquake.usgs.gov/regional/nca/ USGS Menlo Park Seismic Network Operations]
Latest revision as of 19:13, 29 May 2012
Earthquake early warning (EEW) is a technology that can provide rapid information about an earthquake. Under favorable circumstances, EEW technology can provide automated warning of strong ground motions from an earthquake before those ground motions have propagated to all affected sites. EEW technology provides warnings after the earthquake has begun but before the earthquake has affected all users.
EEW forecast capabilities require (a) ground motion (or other) geophysical sensors, (b) scientific processing software, and (c) a communication system distributing information to users. Detailed descriptions of EEW technology can be found here:
SCEC's current research focus on the ShakeAlert project is the development of an automated CISN EEW performance evaluation system. This EEW performance evaluation system, currently called the CISN Testing Center (CTC), is based on the testing framework developed on the SCEC CSEP project.
SCEC4 science plans emphasize the development and use of time-dependent seismic hazard analysis. SCEC earthquake system science research approach seeks to integrate EEW technologies into time-dependent seismic hazard analysis through applications.
CISN and SCEC are collaborating on the development of EEW evaluation tools and techniques. Detailed EEW development notes and current evaluation results are posted on related wiki entries including:
