Magnitude 7.6 Earthquake off the coast of Aomori Prefecture, Japan.

The Japan Meteorological Agency recorded a Magnitude 7.6 Earthquake at a depth of about 50 km, about 80 km off the east coast of Aomori Prefecture, which lies on the northern tip of Honshū Island, at about 11.15 pm Japan Standard Time (about 2.15 pm GMT) on Monday 8 December 2025. Thirty four people were injured as a result of the event, with some damage to buildings and roads. A tsunami warning was issued in the immediate aftermath of the event, causing about 90 000 people to evacuate from low lying areas, but in the event, no major tsunami occurred.  Power supplies were also disrupted, leaving 2700 homes without power, and rail services were temporarily suspended. A number of aftershocks have followed the initial event.

The approximate location of the 8 December 2025 Aomori Prefecture Earthquake. USGS.

Japan has a complex tectonic situation, with parts of the country on four different tectonic plates. Aomori Prefecture lies on the convergent margin where the Okhotsk Plate is pushed against the Eurasian Plate, with the Pacific Plate being subducted beneath the Okhotsk Plate to the east. This is not a smooth process; the rocks of the two plates constantly stick together, only to break apart again as the pressure builds up, causing Earthquakes in the process.

The movement of the tectonic plates beneath Japan. University of Wisconsin Eau Claire.

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Magnitude 7.8 Earthquake off the coast of the Kamchatka Peninsula, Russian Far East.

The United States Geological Survey recorded a Magnitude 7.8 Earthquake at a depth of 19.5 km off the east coast of the Kamchatka Peninsula in the Russian Far East slightly before 2.00 am local time on Friday 19 September 2025 (slightly before 7.00 pm on Thursday 18 September, GMT). Despite the size of this event, no casualties have been reported, although tsunami warnings were triggered across the Pacific. The event is thought to have been an aftershock of a Magnitude 8.8 Earthquake recorded off the coast of the Kamchatka Peninsula in July this year.

The approximate location of the 19 September 2025 Kamchatka Earthquake. USGS.

The Kamchatka Peninsula lies on the eastern edge of the Okhotsk Plate, close to its margin with the Pacific and North American Plates. The Pacific Plate is being subducted along the margin, and as it does so it passes under the southern part of the Kamchatka Peninsula. This is not a smooth process, the rocks of the two plates continuously stick together then, as the pressure builds up, break apart again, causing Earthquakes.

Simple diagram showing the subduction of the Pacific Plate beneath the Okhotsk Plate along the Kuril Trench. Auburn University.

Earthquakes along subductive margins are particularly prone to causing tsunamis, since these often occur when the overlying plate has stuck to the underlying plate, being pulled out of shape by its movement.. Eventually the pressure builds up to far and the overlying plate snaps back, causing an Earthquake and a tsunami.

Simplified graphic showing tsunami generation along a convergent margin. NASA/JPL/CalTech.

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Magnitude 8.8 Earthquake off the Kamchatka Peninsula

The United States Geological Survey recorded a Magnitude 8.8 Earthquake at a depth of 20.7 km off the southeast coast of the Kamchatka Peninsula in the Russian Far East slightly before 11.25 am local time on Wednesday 30 July 2025 (slightly before 11.25 pm on Tuesday 29 July, GMT). A Magnitude of 8.8 makes this the sixth largest Earthquake ever recorded. Despite the size of this event, no casualties have been reported, although the port of Severo-Kurilsk was inundated by a 4 m wave, causing Russian authorities to evacuate the town, and tsunami warnings were triggered across the Pacific.

The approximate location of the 30 July 2025 Kamchatka Earthquake. USGS.

The Kamchatka Peninsula lies on the eastern edge of the Okhotsk Plate, close to its margin with the Pacific and North American Plates. The Pacific Plate is being subducted along the margin, and as it does so it passes under the southern part of the Kamchatka Peninsula. This is not a smooth process, the rocks of the two plates continuously stick together then, as the pressure builds up, break apart again, causing Earthquakes.

Simple diagram showing the subduction of the Pacific Plate beneath the Okhotsk Plate along the Kuril Trench. Auburn University.

Earthquakes along subductive margins are particularly prone to causing tsunamis, since these often occur when the overlying plate has stuck to the underlying plate, being pulled out of shape by its movement.. Eventually the pressure builds up to far and the overlying plate snaps back, causing an Earthquake and a tsunami.

Simplified graphic showing tsunami generation along a convergent margin.NASA/JPL/CalTech.

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Fifty five confirmed deaths following Magnitude 7.6 Earthquake on the Noto Peninsula, Japan.

The Japan Meteorological Agency recorded a Magnitude 7.6 Earthquake at a depth of about 20 km, beneath the Noto Peninsula, part of Ishikawa Prefecture on the north coast of Honshū Island, at about 4.10 pm Japan Standard Time (about 7.10 am GMT) on Monday 1 January 2024. Tens of thousands of buildings are reported to have been damaged or destroyed following the event, with fifty five people confirmed dead at the time of writing, and many more thought to be trapped beneath collapsed buildings. 

The approximate location of the 1 January 2023 Noto Peninsula Earthquake. USGS.

A tsunami warning was issued following the Earthquake, as large tsunami waves triggered such events often add to the problems caused by large Earthquakes in Japan, although on this occasion the largest waves recorded were only about a metre high. Several large aftershocks have been recorded following the initial event, and local officials have warned that these are likely to continue for some time, hampering rescue attempts. A number of fires broke out in the aftermath of the initial Earthquake, adding to the problems. Temperatures in the area typically fall below zero at night at this time of year, adding to concerns about how long people trapped beneath the rubble can survive.

Damage in the city of Wajima on the Noto Peninsula, following a Magnitude 7.6 Earthquake on 1 January 2024. Kyodo/Reuters.

Japan has a complex tectonic situation, with parts of the country on four different tectonic plates. Ishikawa Prefecture lies on the convergent margin where the the Okhotsk Plate is pushed against the Eurasian Plate, with the Pacific Plate being subducted beneath the Okhotsk Plate to the east. This is not a smooth process; the rocks of the two plates constantly stick together, only to break apart again as the pressure builds up, causing Earthquakes in the process.

The movement of the tectonic plates beneath Japan. University of Wisconsin Eau Claire.

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Magnitude 6.3 Earthquake beneath Ishikawa Prefecture leaves one person dead and 22 injured.

The Japan Meteorological Agency recorded a Magnitude 6.3 Earthquake at a depth of about 10 km, beneath Ishikawa Prefecture, on Honshū Island, slightly after 2.40 pm Japan Standard Time (slightly after 5.40 am GMT) on Friday 5 May 2023. The event was felt across much of central Japan and triggered a small tsunami, which was measured at about 10 cm high, and was followed eight hours later by a Magnitude 5.8 aftershock. One person is reported to have died as a result of this Earthquake, a man who fell from a ladder, with 22 people injured, including two who were trapped in collapsed houses in the city of Suzu.

A partially collapsed house in the city of Suzu in Ishikawa Prefecture, Japan, following a Magnitude 6.3 Earthquake on 5 May 2023. Kyodo News.

Japan has a complex tectonic situation, with parts of the country on four different tectonic plates. Ishikawa Prefecture lies on the convergent margin where the the Okhotsk Plate is pushed against the Eurasian Plate, with the Pacific Plate being subducted beneath the Okhotsk Plate to the east. This is not a smooth process; the rocks of the two plates constantly stick together, only to break apart again as the pressure builds up, causing Earthquakes in the process.

The approximate location of the 5 May 2023 Ishikawa Prefecture Earthquake. USGS.

The movement of the tectonic plates beneath Japan. University of Wisconsin Eau Claire.

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