12/25/2022 11:06 AM Weather news
There have been a few earthquakes on the Pacific Ocean side of Hokkaido since Tohoku, and most of them have occurred from the southern part of Kanto to the Izu Islands. In western Japan, earthquakes occur mainly in Kyushu. There have been two earthquakes with a seismic intensity of 3 or greater. (Counting from 10:00 on December 19th to 25th)
Japan: There are many earthquakes related to volcanoes in the sea near Niijima and Kozushima.
It is the first time in about two years since an earthquake with a seismic intensity equal to or greater than 3 occurred in the sea near Niijima and Kozushima on January 1 last year, with a magnitude of 4.7 and a maximum seismic intensity of 4 . Two years ago, there was a swarm of earthquakes in December.
Earthquake swarms often occur in the Izu Islands due to underground magma activity, and there have been several instances of large earthquakes of magnitude 6 or greater, such as in 2000 associated with volcanic activity on Miyakejima. While there are no signs of activity for this quake so far, preparations need to be made on a daily basis.
Japan: earthquake of seismic intensity 4 in northeastern Chiba prefecture
It is the first time in two years and seven months since May 2020 that an earthquake has occurred centered in the northeastern part of Chiba prefecture. The earthquake mechanism is analyzed as a reverse fault type with a pressure axis in the northwest-southeast direction.
Relatively strong earthquakes occurred in the northeastern part of Chiba Prefecture, in the area near Ibaraki Prefecture and in the vicinity of this epicenter. In 2019 we observed a strong quake with a maximum seismic intensity below 5 due to a magnitude 5.1 earthquake with its epicenter a little further inland than this time.
World: Damage caused by M6.4 strong tremors off the coast of Northern California, USA
On the night of the 20th (Tuesday), Japan time, an earthquake with an estimated magnitude of 6.4 and a depth of about 18 km occurred off the coast of Northern California, USA. The seismic mechanism is analyzed as strike-slip. Because it occurred relatively close to land, the coastal area is believed to have experienced an earthquake of VIII on the revised Mercalli seismic intensity scale.
In areas where the tremors were strong, bridges and roads cracked and power outages occurred.
The epicenter of this earthquake was near the boundary of three plates: the Pacific Plate, the North American Plate and the Fandeca Plate, an area where many large earthquakes occur. Exactly one year ago, on December 20, there was a magnitude of 6.2. An earthquake measuring 7.2 also occurred in 2005, although the epicenter was a little further away.
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*Information on earthquake sources and seismic intensity in Japan is from the Japan Meteorological Agency unless otherwise specified. Overseas epicenter information is from the United States Geological Survey (USGS) unless otherwise noted. There may be differences in hypocenter information depending on the publishing organization.