Seismogeodetic early warning system: A step forward in tsunami and earthquake warning and mitigation

Jonatan Glehman

Submitted September 7, 2025, SCEC Contribution #14497, 2025 SCEC Annual Meeting Poster #TBD

Rapid and accurate estimation of earthquake magnitude is crucial for early warning systems, particularly for coastal populations vulnerable to tsunami and seismic hazards. Traditional approaches relying on regional or teleseismic data introduce delays that limit their effectiveness near the source. In this study, we enhance the seismogeodetic approach for moment magnitude estimation (Mwg) by addressing limitations in the existing approach. Using a dataset of eight moderate-to-large earthquakes with diverse faulting styles, we extend the framework to incorporate S-wave contribution and seismic radiation patterns. We show that these modifications significantly improve accuracy, particularly for strike-slip and normal fault events.
We further expand the method’s applicability by interpolating coseismic windows from collocated GNSS and accelerometer stations to stand-alone GNSS. This nearly doubles the usable network and maintains magnitude estimation errors within ±0.2 units of Mwg. While radiation pattern corrections offer substantial benefits for thrust and normal faulting events, we find they can be omitted for strike-slip events in real-time applications. Our findings support an adaptive workflow that leverages tectonic context (e.g., Slab2 geometry) to inform model selection, emphasizing the importance of network geometry and station density. These results enhance real-time earthquake and tsunami early warning capabilities by improving the robustness of magnitude estimation across varying faulting styles and network configurations.

Citation
Glehman, J. (2025, 09). Seismogeodetic early warning system: A step forward in tsunami and earthquake warning and mitigation. Poster Presentation at 2025 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology