American Geophysical Union, Geophysical Research Letters, 23(41), p. 8269-8276, 2014
DOI: 10.1002/2014gl061923
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Recently, progress has been made to demonstrate feasibility and benefits of including real-time GPS (rtGPS) in earthquake early warning and rapid response systems. Most concepts, however, have yet to be integrated into operational environments. The Berkeley Seismological Laboratory runs an rtGPS based finite fault inversion scheme in real-time. This system (G-larmS) detected the 2014 Mw 6.0 South Napa earthquake in California. We review G-larmS’ performance during this event and 13 aftershocks and present rtGPS observations and real-time modeling results for the main shock. The first distributed slip model and magnitude estimates were available 24 s after the event origin time, which, after optimizations, was reduced to 14 s (≈8 s S-wave travel time, ≈6 s data latency). G-larmS’ solutions for the aftershocks (that had no measurable surface displacements) demonstrate that, in combination with the seismic early warning magnitude, Mw 6.0 is our current resolution limit.