Defining the nature of faulting, the stress needed to trigger earthquakes, and the stress state of faults remains fundamental to understanding the earthquake cycle. Studying remote dynamic triggering allows us to probe faults to systemically address the fundamental physical mechanisms of faulting. Using 13 years of data (2004–2016) from the EarthScope USArray Transportable Array and the Southern California Seismic Network, we search for remotely triggered seismicity in an extended region encompassing the Coso Geothermal Field (CGF+), California. We first apply a short term to long‐term average ratio detector to high‐pass (5 Hz) filtered waveforms spanning ±5 hr encompassing 211
Remote earthquake triggering is a well-established phenomenon. Triggering is commonly identified from statistically significant increases in earthquake rate coincident with the passage of seismic energy. In establishing rate changes, short duration earthquake catalogs are commonly used, and triggered sequences are not typically analyzed within the context of background seismic activity. Using 500 mainshocks and four western USA 33-yearlong earthquake catalogs, we compare the ability of three different statistical methods to identify remote earthquake triggering. Counter to many prior studies, we find remote dynamic triggering is rare (conservatively, <2% of the time). For the mainshocks associated with remote rate increases, the spatial and temporal signatures of triggering differ. We find that a rate increase coincident in time with mainshock energy alone is insufficient to conclude that dynamic triggering occurred. To classify dynamically triggered sequences, we suggest moving away from strict statistical measurements and instead use a compatibility assessment that includes multiple factors, like spatial and temporal indicators.
more » « less- NSF-PAR ID:
- 10154074
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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