At least 34 dead following Magnitude 7.1 Earthquake beneath Kumamoto Prefecture, Japan.

The Japan Meteorological Agency recorded a Magnitude 7.1 Earthquake at a depth of about 10 km, beneath Kumamoto Prefecture on Kyūshū Island, slightly before 4.30 pm Japan Standard Time (slightly before 7.30 am GMT) on Tuesday 28 July 2026. At least 34 people have died following this event, and many more are still missing, most of them within a shopping centre which collapsed during the Earthquake, and where an explosion occurred about an hour later, probably due to a broken gas main. The Earthquake was felt across western Japan, and more than 100 aftershocks have been recorded since the original event.

The approximate location of the 28 July 2026 Kumamoto Prefectiure Earthquake. USGS.

Around 30 000 households lost power following the event, and around 80 000 have lost water supplies. More than 1000 people have been evacuated to temporary shelters, while civil engineers make safe their residences. Managing this evacuation is proving to be particularly difficult, as many evacuation centres have also lost electricity and water suppliers. The area is currently also suffering from a heatwave, with temperatures reaching as high as 39°C, and around 30% of those evacuated have been described as elderly and vulnerable to the heat.

A collapsed building in the city of Yatsushiro in Kumamoto Prefecture following the 28 July 2026 Earthquake. Hiro Komae/AP.

Japan has a complex tectonic environment with four plates underlying parts of the Islands; in addition to the Pacific in the east and the Othorsk in the North, there are the Philipine Plate to the south and the Eurasian Plate to the West. Kyūshū Island lies at the northeast end of the Ryukyu Island Arc, which sits on top of the boundary between the Eurasian and Philippine Plates. The Philippine Plate is being subducted beneath the Eurasian Plate, in the Ryukyo Trench, to the Southeast of the Islands. This is not a smooth process, with the two plates continuously sticking together then breaking apart as the pressure builds up, leading to frequent Earthquakes in the region.

The movement of the Pacific and Philippine Plates beneath eastern Honshū. Laurent Jolivet/Institut des Sciences de la Terre d'Orléans/Sciences de la Terre et de l'Environnement.

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Magnitude 6.2 Earthquake in the Coquimbo Region of Chile.

The United States Geological Survey recorded a Magnitude 6.2 Earthquake at a depth of 36.9 km, roughly 32 km to the southwest of the city of Ovale in Limari Province, part of the Atacama Coquimbo of Chile, slightly before 10.35 am local time (slightly before 1.35 pm GMT) on Thursday 12 February 2026. There are no reports of any damage or injuries associated with this event, but people have reported feeling it as far away as Santiago, 400 km to the south.

The location of the 12 February 2026 Coquimbo Earthquake. USGS.

Chile is located on the west coast of South America, which is also the convergent margin between the Nazca and South American Plates. The Nazca Plate is being subducted beneath the South American Plate and is sinking beneath the South American Plate. 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. As the Nazca Plate sinks deeper it is partially melted by the heat of the Earth's interior. Some of the melted material then rises up through the overlying South American Plate as magma, fuelling the volcanoes of the Chilean Andes.

The subduction of the Nazca Plate beneath the South American Plate, and how it causes Earthquakes and volcanoes. Pacific Earthquake Engineering Research Center.

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Magnitude 6.8 Earthquake beneath the Hubbard Glacier on the border between Alaska and Canada's Yukon Territory.

The Alaska Earthquake Centre recorded a Magnitude 6.8 Earthquake at a depth of 3 km, beneath the Hubbard Glacier on the border between Alaska and Canada's Yukon Territory, slightly after 11.40 am Alaskan Standard Time (slightly before 8.40 pm GMT) on Saturday 6 December 2025. Earthquakes Canada recorded the same event as a Magnitude 7.0 Earthquake at a depth of 10 km. There are no reports of any damage or casualties associated with this event, but people have reported feeling it over a wide area of eastern Alaska, the Yukon, British Colombia, and parts of Washington State.

The approximate location of the 6 December 2025 Hubbard Glacier Earthquake. USGS.

Alaska lies on the North American Plate, with the Pacific Plate underlying the ocean to the south. The Aleutian Trench runs along much of the south coast of Alaska, with the Pacific Plate being subducted beneath this and passing under Alaska as it sinks into the Earth. Off the coast of southeast Alaska the Pacific and North American Plates pass one-another horizontally, with the Pacific Plate moving northward and the North American to the south (a transform plate margin). This is not a smooth process, and the plates frequently stick together, then break apart as the pressure builds up, causing Earthquakes.

How the subduction of the Pacific Plate beneath the North American Plate fuels the volcanoes of Alaska. Alaska Volcano Observatory.

Witness accounts of quakes can help geologists to understand these events and the rock structures that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) you can report it to the United States Geological Survey here, or Earthquakes Canada here.

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Magnitude 6.2 Earthquake off the west coast of Sumatra.

The Indonesian Meteorological, Climatological, and Geophysical Agency recorded a Magnitude 6.2 Earthquake at a depth of about 29 km, off the West coast of Aceh Province, Sumatra, Indonesia slightly after 6.00 pm Western Indonesian Time (slightly after 11.00 am GMT) on Tuesday 31 January 2025. There have been no reports of any damage or casualties following this event, but people have reported feeling  tremors  across Aceh Province and parts of North Sumatra.

The approximate location of the 31 January 2025 Aceh Province Earthquake. USGS.

The Indo-Australian Plate, which underlies the Indian Ocean to the west of Sumatra, is being subducted beneath the Sunda Plate, a breakaway part of the Eurasian Plate which underlies Sumatra and neighbouring Java, along the Sunda Trench, passing under Sumatra, where friction between the two plates can cause Earthquakes. As the Indo-Australian Plate sinks further into the Earth it is partially melted and some of the melted material rises through the overlying Sunda Plate as magma, fueling the volcanoes of Sumatra.

The Subduction zone beneath Sumatra. NASA/Earth Observatory.

This does not happen at a 90° angle, as occurs in the subduction zones along the western margins of North and South America, but at a steeply oblique angle. This means that as well as the subduction of the Indo-Australian plate beneath the Sunda, the two plates are also moving past one-another. This causes rifting within the plates, as parts of each plate become stuck to the other, and are dragged along in the opposing plate's direction. The most obvious example of this is the Sumatran Fault, which runs the length of Sumatra, with the two halves of the island moving independently of one-another. This fault is the cause of most of the quakes on the island, and most of the island's volcanoes lie on it.

The movement of the tectonic plates around Sumatra. NASA/Earth Observatory.

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Magnitude 6.7 Earthquake off the east coast of Taiwan.

The Taiwan Central Weather Bureau reported a Magnitude 6.7 Earthquake at a depth of 62.6 km off the eastern coast of Taiwan, slightly after 1.40 am local time on Wednesday 23 March 2022 local time (slightly after 5.40 pm on Tuesday 22 March, GMT). There are no reports of any damage or casualties at this time, but it was felt across the island, and on parts of the Chinese mainland.

 

The approximate location of the 23 March 2022 Taiwan Earthquake. USGS.

Taiwan has a complex tectonic setting, lying on the boundary between the Eurasian and Philippine Plates, with the Eurasian Plate being subducted beneath the Philippine Plate in the South and the Philippine Plate being subducted beneath the Eurasian in the East. Subduction is not a smooth process even in simple settings, with plates typically sticking together as pressure from tectonic expansion elsewhere builds up, then suddenly breaking apart and shifting abruptly, causing Earthquakes.

 

The motion of the tectonic plates beneath Taiwan. The University of Memphis.

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