Seismic Activity of "the 2024 Noto Peninsula Earthquakes"
On January 1, 2024 at 16:10 (JST, hereinafter the same time), there was an M7.6 earthquake (maximum seismic intensity 7) at a depth of 16 km in the Noto region, Ishikawa Prefecture. There was a high seismic activity before and after the earthquake: just before at 16:06, an M5.5 (maximum seismic intensity 5 Upper) one, and just after the M7.6 earthquake, at 16:12 an M5.7 (maximum seismic intensity 6 Lower) one, and at 16:18 an M6.1 (maximum seismic intensity 5 Upper) one.
The activity area of the recent earthquake extends about 150 km in an NE-SW direction, centering on the Noto Peninsula and its northeastern sea area. The focal mechanism (CMT solution) of the M7.6 earthquake showed a reverse fault type with a compression axis in an NW-SE direction.
The M7.6 earthquake caused tsunami observed at a wide area centering on the Sea of Japan coast of the area extending from Hokkaido to Kyushu, such that of height 80 cm observed at Kanazawa observatory (#1), and of height 0.8 m observed at Sakata observatory (#2). Also from field surveys, at Funami Park, Joetsu City, Niigata Prefecture, tsunami trace of 5.8 m (run-up height) was recognized.
In the Noto Peninsula the seismic activity became high since December 2020, and on May 5, 2023, there was an M6.5 earthquake (maximum seismic intensity 6 Upper).
The largest scale earthquake in February 2024 was an M5.2 earthquake (maximum seismic intensity 4) on 7th at 06:08. The number of earthquakes is gradually decaying as a whole, repeating rise and fall, but the active state still continues in March: till 8th at 08 o'clock there were 25 earthquakes with seismic intensity 1 or over observed.
Japan Meteorological Agency
[Evaluation of Seismic Activities for February 2024 (March 11, 2024)]