In a newly published study, U.S. Geological Survey scientists and their partners calculate possible alert times that earthquake early warning systems can provide people at different levels of ground motion from light to very strong shaking.
Results of scientific studies such as this can be used to design alerting strategies for earthquake early warning systems such as USGS’ ShakeAlert, now being developed for the U.S. West Coast.
This new study examines what the expected warning times could be for earthquake early warning systems by considering how long it takes an earthquake to grow in size (magnitude) compared to how long it takes earthquake waves (shaking) to arrive at a user’s location.
Modern earthquake early warning systems can monitor the evolving rupture, issuing alerts to regions expected to experience a certain level of shaking as the earthquake is occurring. If the earthquake rupture grows, and the region impacted by ground motion expands, alerts may be updated and extended to new locations. A person will experience very strong ground motions only if the earthquake grows to a large-enough magnitude and if the fault rupture breaks close to their location.
Continue reading at USGS.
Image via USGS.