Self-contained local broadband seismogeodetic early warning system: Detection and location

 Example of early warning products for 2016 M w 5.2 Borrego Springs event.

Example of early warning products for 2016 M w 5.2 Borrego Springs event.

TitleSelf-contained local broadband seismogeodetic early warning system: Detection and location
Publication TypeJournal Article
Year of Publication2017
AuthorsGoldberg D.E, Bock Y
JournalJournal of Geophysical Research-Solid Earth
Volume122
Pagination3197-3220
Date Published2017/04
Type of ArticleArticle
ISBN Number2169-9313
Accession NumberWOS:000401867200041
Keywords1-hz gps; accelerometers; algorithm; california; displacement; early warning; earthquake; earthquake detection; hypocenter; motion; picking; records; seismogeodesy
Abstract

Earthquake and local tsunami early warning is critical to mitigating adverse impacts of large-magnitude earthquakes. An optimal system must rely on near-source data to maximize warning time. To this end, we have developed a self-contained seismogeodetic early warning system employing an optimal combination of high-frequency information from strong-motion accelerometers and low-frequency information from collocated Global Navigation Satellite Systems (GNSS) instruments to estimate real-time displacements and velocities. Like GNSS, and unlike broadband seismometers, seismogeodetic stations record the full waveform, including static offset, without clipping in the near-field or saturating for large magnitude earthquakes. However, GNSS alone cannot provide a self-contained system and requires an external seismic trigger. Seismogeodetic stations detect Pwave arrivals with the same sensitivity as strong-motion accelerometers and thus provide a stand-alone system. We demonstrate the utility of near-source seismogeodesy for event detection and location with analysis of the 2010 M(w)7.2 El Mayor-Cucapah, Baja, California and 2014 M(w)6.0 Napa, California strike-slip events, and the 2014 M(w)8.2 Iquique, Chile subduction zone earthquake using observatory-grade accelerometers and GPS data. We present lessons from the 2014 M(w)4.0 Piedmont, California and 2016 M(w)5.2 Borrego Springs, California earthquakes, recorded by our seismogeodetic system with Micro-Electro Mechanical System (MEMS) accelerometers and GPS data and reanalyzed retrospectively. We conclude that our self-contained seismogeodetic system is suitable for early warning for earthquakes of significance (>M5) using either observatory-grade or MEMS accelerometers. Finally, we discuss the effect of network design on hypocenter location and suggest the deployment of additional seismogeodetic stations for the western U.S.

DOI10.1002/2016jb013766
Impact: 

We have described the elements of our seismogeodetic earthquake and tsunami early warning system, where the detection and location algorithms initiate higher-order products such as earthquake magnitude scaling, and centroid moment tensor and finite fault slip solutions. These higher-order products can then be used as input to local tsunami prediction and modeling algorithms. The seismogeodetic method allows for a self-contained earthquake early warning system that utilizes the best qualities of seismic and geodetic approaches to earthquake and local tsunami early warning.

Student Publication: 
Yes
Student: 
sharknado