SCEC Award Number 14201 View PDF
Proposal Category Individual Proposal (Integration and Theory)
Proposal Title Enhanced Earthquake Early Warning and Response Through GPS/Seismic Integration
Investigator(s)
Name Organization
Yehuda Bock University of California, San Diego
Other Participants Diego Melgar, Dara Goldberg, Jessie Saunders
SCEC Priorities 6d, 5b SCEC Groups Geodesy, Seismology, Transient Detection
Report Due Date 03/15/2015 Date Report Submitted N/A
Project Abstract
 We have made significant progress in all four seismogeodetic objectives.
(1) Improve real-time estimation of earthquake magnitude and intensity: Completed a seismic trigger based on the seismogeodetic velocities for the four stations nearest the epicenter, followed by a hypocenter calculation and P wave and S wave propagation, which is refined as data from more stations become available. Results presented by graduate student Dara Goldberg at SSA meeting.
(2) Develop P wave and PGD magnitude scaling relationships: We added analysis of more earthquakes to improve the PGD magnitude scaling relationship. Paper by Melgar et al. (2015a) submitted to Geophys. Res. Lett.
(3) Investigate appropriate methodologies to compute full finite fault slip models: Completed software package for kinematic and static inversions and published a paper on application for the 2011 Mw 9.0 Tohoku-Oki earthquake in Japan (Melgar and Bock, 2015) and the 2014 Napa Valley earthquake (Melgar et al., 2015b).
(4) Deploy SIO Geodetic Module and a MEMS accelerometer package at existing real-time GPS stations: We have completed this task for southern California and 15 stations are collecting seismogeodetic data and we’re processing displacement and velocity waveforms on an operational basis. Data are stored at SCEDC. We provided UNAVCO with 10 upgrade packages and they installed ten units in the Bay Area. The packages were successfully tested at the UCSD outdoor shake table (LHPOST). Seismogeodetic waveforms estimated from GPS+SIO MEMS accelerometers compared well with GPS+EpiSensor accelerometer. Results presented at SSA meeting by graduate student Jessie Saunders.
Intellectual Merit The research has contributed to improvements in earthquake early warning and rapid response, as well tsunami prediction, using seismogeodesy. Creative concepts using seismogeodetic displacement and velocity waveforms: Pd and PGD magnitude scaling relationships, finite CMT solutions, and static and kinematic finite-fault slip inversions for thrust and strike-slip environments. Resolves magnitude saturation problem with seismic-only systems and allows rapid results (fault models by the end of seismic shaking) using data collected within the earthquake's epicentral region, where most of the losses occur, and beyond.
Broader Impacts The project to date has supported directly or indirectly four graduate students at SIO (two female, one Hispanic) and a postdoctoral researcher. Two graduate PhD student are now working on earthquake early warning and rapid modeling at U Washington and UC Berkeley. The project has also contributed to infrastructure and data openly available to the community, including 25 seismogeodetic upgrades (15 in SoCal and 10 in NoCal). Data are archived at SCEDC, UNAVCO and IRIS. Project contributes to systems designed to mitigate the effects of natural hazards, a direct benefit to society.
Exemplary Figure Figure 2. Magnitude scaling of peak ground displacement measurements (PGD) based on 10 GPS-measured earthquakes from magnitude 6 to magnitude 9. The oblique lines are the predicted scaling values from the L1 regression of the PGD measurements as a function of hypocentral distance. Modified from Melgar et al. (2015), Geophys. Res. Lett.