January 14, 2026
Earthquake Research Committee,
Headquarters for Earthquake Research Promotion
Approximately two years have passed since the M7.6 Noto Peninsula Earthquake of January 1, 2024. In this summary, we compile the latest seismic activity data, utilizing survey and observation findings from governmental agencies, universities, and other research institutions.
For comprehensive details on past seismic activity and crustal deformation, please refer to the "View of the Earthquake Research Committee Chairman" on the Seismic Activity in the Noto Region, Ishikawa Prefecture," published in July 2022, and the "‘View of the Earthquake Research Committee Chairman’ on the ‘2024 Noto Peninsula Earthquakes’," published in January 2025.
* Since December 2020, seismic activity has surged within an area of approximately 30 km2 in the northeastern part of the Noto Peninsula in the Noto region, Ishikawa Prefecture. Initially, this activity was characterized by a series of relatively small earthquakes, but it soon escalated to include larger events, such as an M5.4 earthquake in June 2022 and an M6.5 earthquake in May 2023. In January 2024, the largest event in the sequence occurred, with an M7.6. Immediately following this, seismic activity surged within a radius of approximately 150 km, extending in the NE-SW direction. Over time, the activity within the activity zone of the M7.6 earthquake has gradually decreased. However, an M6.0 earthquake occurred in June 2024, followed by an M6.6 earthquake in November 2024.
* During this period, there were 70 earthquakes registering seismic intensity 1 or greater that occurred in 2021, 195 in 2022, 241 in 2023, 2,123 in 2024, and 125 in 2025. Although the frequency of earthquakes has declined since the M7.6 earthquake, seismic activity remains high compared to the levels before 2021, when the activity initially surged.
* From December 2020, when seismic activity surged, until the M6.5 earthquake on May 5, 2023, GNSS observations recorded a significant crustal deformation in the northeastern Noto Peninsula. This included more than 1 cm of horizontal displacement and approximately 4 cm of uplift at the Suzu observation point.
Following the M6.5 earthquake, a horizontal displacement of approximately 9 cm was observed at the M-Suzu-Sasanami observation point, and an uplift of approximately 13 cm was observed at the M-Suzu-Noroshi observation point, both located near the epicenter. Between the M6.5 earthquake and the M7.6 earthquake on January 1, 2024, many observation points showed deformations that deviated from the pre-earthquake trends, but these deformations decreased over time.
Following the M7.6 earthquake, significant crustal deformation was observed over a wide area centered on the Noto Peninsula, extending from the Chubu to the Kanto regions. This included approximately 2 m of horizontal displacement and approximately 1.3 m of uplift in the southwest direction at the Wajima-2 observation point. After the M7.6 earthquake, although at a slower pace, crustal deformation, believed to be postseismic deformation centered on the Noto Peninsula, persists across a wide area, encompassing Ishikawa, Toyama, Niigata, and Nagano Prefectures.
* Recent GNSS observations indicate that while the postseismic deformation following the M7.6 earthquake has decreased, the significant expansionary crustal deformation observed in the northeastern Noto Peninsula since December 2020 has yet to be confirmed. Furthermore, within the M7.6 earthquake's activity zone, the background seismic activity level (#2) for earthquakes of magnitude 3.0 or greater has returned to the level observed at the onset of increased seismic activity in December 2020. This suggests that activity has largely returned to normal since December 2020.
However, seismic activity directly linked to the M7.6 earthquake may continue at the current level for an extended period, ranging from several months to years (several earthquakes of seismic intensity 1 or greater occurring each month).
* Previous analyses of electrical conductivity (#3) and seismic wave data suggested that the activity since December 2020 has likely involved some form of fluid intrusion. Subsequent geochemical observations conducted in the northeastern Noto Peninsula from June 2022 to October 2024 indicate that this series of events can be attributed to fluids ascending from the mantle.
* On the Sea of Japan side, earthquakes of around M6.0 have occurred even several years after the largest earthquake, such as the 1983 Central Sea of Japan Earthquake (M7.7). Additionally, near the Noto Peninsula, large earthquakes causing damage, like the Noto Hanto Earthquake in 2007 (M6.9), occurred even before the onset of the current seismic activity in December 2020.
* According to the "Long-term Evaluation of Offshore Active Faults in the Central and Southern Sea of Japan Area (First Edition)." For Offshore Northern Kinki and Hokuriku Regions" by the Earthquake Research Committee (published on June 27, 2025), the source fault of the M7.6 earthquake is estimated to stretch approximately 150 km in a NE-SW direction. This fault spans from the offshore east of the Monzen section of the Monzen Fault Zone, through the Noto Peninsula North Coast Fault Zone, to the southwest of the Western Margin Fault of the Toyama Trough. Note that active faults in the surrounding area may have been impacted in ways that could trigger further seismic activity. Moreover, in the activity zone of the M7.6 earthquake, beyond the already-evaluated active faults both on land and offshore, there may be faults capable of generating earthquakes whose traces are not clearly visible either in the shallow seabed or at the surface. Thus, continuous vigilance is required.
Note: GNSS refers to a generic term for satellite positioning systems, including GPS.
#1: Name established by the Japan Meteorological Agency for the M7.6 earthquake on January 1, 2024 in the Noto region, Ishikawa Prefecture, and a series of seismic activities since December 2020.
#2: A statistical model (non-stationary ETAS model) is used to quantify seismic activity. This model assumes that parameters describing the background seismicity and aftershock productivity vary with time and can evaluate long-lasting seismic activity.
#3: Electrical conductivity indicates how easily electricity flows. Generally, the presence of subsurface substances, such as water, facilitates electrical flow.