From Boutique to Wholesale Seismic Monitoring: Performance Evaluation Tools to Prepare a Traditional Regional Seismic Network for Earthquake Early Warning

Date: 4/24/2019

Time: 06:00 PM

Room: Fifth Avenue

The ShakeAlert Earthquake Early Warning (SAEEW) system combines data from three Regional Seismic Networks (RSNs) to produce real-time shaking alerts for the US west coast. In Oregon and Washington states, the contributing RSN is the Pacific Northwest Seismic Network (PNSN). SAEEW has necessitated RSNs to evaluate metrics that challenge traditional RSN capabilities even to evaluate. The additional requirements include robust measures of station density, product latency (combining data telemetry and seismic propagation factors), and the distribution of stations with respect to specific hazards. Moreover, differences in hazard characteristics along the west coast combined with variations in RSNs states of technical development may make it difficult to generate a synoptic SAEEW-wide performance assessment, although this is frequently requested for accounting and political purposes. These needs stretch the RSNs traditional station-by-station data quality assessment tools and favor an approach that produces simple views of the overall capability of the network to generate high-quality products. We present the results of a set of map-based python-implemented forward modeling studies to assess overall network performance of the entire ShakeAlert network on the west coast of the US. These include assessments of the density of seismic stations, the time to produce a warning, and the size of the zone surrounding the epicenter of an earthquake point source that would receive late warning. Our modeling permits us to easily assess where future instrumentation would have the greatest impact, what the impact would be of loss of data from stations, and how improving station performance would benefit the ShakeAlert performance (or not). Our models provide an abundance of detailed evaluations of expected product performance that we compare directly to the hazard and system performance standards. Overall, our models reveal that average station density, the depths of earthquakes, and data delivery latency are primary determinants for overall EEW system performance.

Presenting Author: Jon Connolly

Authors