Coseismic crustal seismic velocity changes associated with the 2024 M_W 7.5 Noto earthquake, Japan.

ABSTRACT:  The 2024 Mw 7.5 Noto earthquake, Japan, was preceded by an intense seismic swarm thought to be driven by upward fluid migration. Crustal seismic velocities vary with external perturbations caused by earthquakes, and the presence of pressurized fluids in the crust amplifies the resulting coseismic velocity change. Hence, we characterize subsurface fluid by measuring the coseismic velocity change associated with the 2024 mainshock. For this purpose, we perform multi-frequency-band ambient noise seismic interferometry using data from permanent and temporary seismic stations. Significant coseismic velocity drops are observed, with an average decrease of about 0.5% inside the Noto peninsula, reaching 0.6-0.8% in the regions near the coseismic slip peaks. The observed velocity drops inside the

SUBMITTER: Paris N 

PROVIDER: S-EPMC12011933 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature