Automatic finite earthquake source inversion using real-time GNSS and teleseismic data for tsunami early warning
Abstract
Fast finite earthquake source inversion is critical to tsunami scale determination for reliable tsunami early warning to save lives. Recently, it has been demonstrated that near-field Global Navigation Satellite System (GNSS) data are especially valuable to constrain fast finite source inversion, which results in the proposition of GNSS-based tsunami early warning systems. However, the real-time GNSS stations are only available in limited regions worldwide and can be too sparse to be used in many cases.
We have developed an automatic finite source inversion system using both near-field (<1000 km) GNSS data and far-field (between 3000 4500 km) teleseismic P-waves. When there are dense enough near-field GNSS data available, our system will produce slip distributions within minutes. If not, relying on the teleseismic P-waves (within 6 8 minutes away from the epicenter), slip distribution can still be inverted within 15 minutes. Here we present the framework of the algorithm and test its performance for both retrospective and real-time events. To be specific, for events with abundant GNSS data (e.g., the 2011 Mw 9.1 Tohoku earthquake), reliable co-seismic slip distribution is typically available within two minutes. In case of insufficient GNSS observations (e.g., the 2015 Mw 8.2 Illapel event), joint inversion based on GNSS and teleseismic P waves provides good estimation of rupture asperites. For earthquakes without near-field GNSS data (e.g., the 2016 Mw 7.8 Solomon event), basic features of the earthquake slip are obtained and the predicted tsunamis agree with the observations reasonably well. The system has been incorporated in the prototype of JPL's GPS-Aided Tsunami Early-detection System (GATES) for real-time testing.- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMNH43E1091C
- Keywords:
-
- 4304 Oceanic;
- NATURAL HAZARDSDE: 4313 Extreme events;
- NATURAL HAZARDSDE: 4341 Early warning systems;
- NATURAL HAZARDSDE: 7215 Earthquake source observations;
- SEISMOLOGY