TY - JOUR
T1 - Monitoring seismic velocity changes across the San Jacinto Fault using train-generated seismic tremors
AU - Sheng, Y.
AU - Mordret, A.
AU - Sager, K.
AU - Brenguier, F.
AU - Boué, P.
AU - Rousset, B.
AU - Vernon, F.
AU - Higueret, Q.
AU - Ben-Zion, Y.
N1 - Publisher Copyright:
© 2022. The Authors.
PY - 2022/10/16
Y1 - 2022/10/16
N2 - Microseismic noise has been used for seismic velocity monitoring. However, such signals are dominated by low-frequency surface waves that are not ideal for detecting changes associated with small tectonic processes. Here we show that it is possible to extract stable, high-frequency body waves using seismic tremors generated by freight trains. Such body waves allow us to focus on small velocity perturbations in the crust with high spatial resolution. We report on 10 years of seismic velocity temporal changes at the San Jacinto Fault. We observe and map a two-month-long episode of velocity changes with complex spatial distribution and interpret the velocity perturbation as produced by a previously undocumented slow-slip event. We verify the hypothesis through numerical simulations and locate this event along a fault segment believed to be locked. Such a slow-slip event stresses its surroundings and may trigger a major earthquake on a fault section approaching failure.
AB - Microseismic noise has been used for seismic velocity monitoring. However, such signals are dominated by low-frequency surface waves that are not ideal for detecting changes associated with small tectonic processes. Here we show that it is possible to extract stable, high-frequency body waves using seismic tremors generated by freight trains. Such body waves allow us to focus on small velocity perturbations in the crust with high spatial resolution. We report on 10 years of seismic velocity temporal changes at the San Jacinto Fault. We observe and map a two-month-long episode of velocity changes with complex spatial distribution and interpret the velocity perturbation as produced by a previously undocumented slow-slip event. We verify the hypothesis through numerical simulations and locate this event along a fault segment believed to be locked. Such a slow-slip event stresses its surroundings and may trigger a major earthquake on a fault section approaching failure.
KW - Anza seismic gap
KW - body-wave correlation functions
KW - hidden slow-slip event
KW - long-base seismic interferometry
KW - train-generated seismic energy
UR - http://www.scopus.com/inward/record.url?scp=85139501631&partnerID=8YFLogxK
U2 - 10.1029/2022GL098509
DO - 10.1029/2022GL098509
M3 - Article
AN - SCOPUS:85139501631
SN - 0094-8276
VL - 49
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 19
M1 - e2022GL098509
ER -