(7) Recent Earthquake in Japan
On 1 January 2024, a magnitude 7.5 earthquake jolted Japan's Noto Peninsula at 16:10 local time, following a M5.5 foreshock just minutes earlier (Toda and Stein, 2024). This seismic event is part of a series, starting with a M6.7 earthquake in March 2007 to the west of the peninsula (e.g., Yoshida et al., 2023; Shelly et al., 2024; Amezawa et al., 2023; Kato (2023). Since late 2020, a seismic swarm has persisted in the same area as the M7.5 earthquake, with the largest earthquake being a M6.3 event that took place in May 2023. Both the seismic swarm and the migration of the aftershocks from the M6.3 event have been linked to upward fluid migration from depth within the fault zone. Ongoing analysis of the 2024 M7.5 earthquake, and the preceding swarms combined with numerical modeling and observations of fluids and swarms elsewhere has potential to aid future forecasting of earthquake swarm evolution.
Sources:
Amezawa, Y., Hiramatsu, Y., Miyakawa, A., Imanishi, K.,& Otsubo, M. (2023). Long-living earthquake swarm and intermittent seismicity in the northeastern tip of the Noto Peninsula, Japan. Geophysical Research Letters, 50, e2022GL102670. https://doi.org/10.1029/2022GL102670
Kato, A. (2024). Implications of fault-valve behavior from immediate aftershocks following the 2023 Mj6.5 earthquake beneath the Noto Peninsula, central Japan. Geophysical Research Letters, 51, e2023GL106444. https://doi.org/10.1029/2023GL106444
Shelly, D. R. (2024). Examining the connections between earthquake swarms, crustal fluids, and large earthquakes in the context of the 2020–2024 Noto Peninsula, Japan, earthquake sequence. Geophysical Research Letters, 51, e2023GL107897. https://doi.org/10.1029/2023GL107897
Toda, S., and Stein, Ross S., 2024, Intense seismic swarm punctuated by a magnitude 7.5 Japan shock, Temblor, http://doi.org/10.32858/temblor.333
Yoshida, K., Uchida, N., Matsumoto, Y., Orimo, M., Okada, T., Hirahara, S., et al. (2023). Updip fluid flow in the crust of the northeastern Noto Peninsula, Japan, triggered the 2023 Mw 6.2 Suzu earthquake during swarm activity. Geophysical Research Letters, 50, e2023GL106023. https://doi.org/10.1029/2023GL10602