Tectonic Hotspots: the Week's Most Powerful Earthquakes Ranked

A magnitude 6.0 earthquake struck 12 km west of the resort town of Anacapri on the island of Capri on 6 March 2026 — a reminder that Italy's picture-postcard coastlines sit above one of Europe's most volatile tectonic environments. The Campanian volcanic arc, home to Vesuvius, Stromboli, and the Campi Flegrei supervolcano, is underlain by the collision between the Eurasian and African plates. Thirteen people reported feeling this event; the USGS estimated a maximum instrumental intensity of only 3 on the modified Mercalli scale, suggesting the moderate depth of 10 km attenuated surface shaking.

A magnitude 5.9 earthquake struck 21 km northeast of Otobe in southern Hokkaido, Japan on 5 March 2026. Japan is one of the world's most seismically active nations — the country sits at the junction of four tectonic plates and experiences roughly 1,500 earthquakes strong enough to be felt each year. Southern Hokkaido sits above the Japan Trench, where the Pacific Plate subducts beneath the Okhotsk microplate at a rate of approximately 9 cm per year. At 4.2 km depth, this was a notably shallow event, maximising local shaking intensity even though the 5.9 magnitude produced no casualties.

A magnitude 5.9 earthquake struck 160 km south-southeast of the naval city of Vilyuchinsk on the Kamchatka Peninsula on 4 March 2026. Kamchatka is arguably the most seismically intense landmass on Earth — the peninsula sits directly above the convergence of the Pacific and North American plates, and the Kamchatka subduction zone has produced several of the largest earthquakes in recorded history, including the 1952 Kamchatka earthquake at magnitude 9.0. At 10 km depth and with no felt reports due to the remote location, this event was significant only geologically — a reminder that the Peninsula is never truly at rest.

A magnitude 5.9 earthquake struck 15 km west-southwest of the Tongan island of Niuatoputapu on 4 March 2026 — the same chain of islands devastated by the catastrophic Hunga Tonga–Hunga Ha'apai volcanic eruption and tsunami in January 2022. Tonga sits at the western edge of the Pacific Plate, where it subducts beneath the Australian Plate at the Tonga Trench — one of the deepest ocean trenches on Earth and one of the most seismically active subduction zones. Eight people reported feeling this event; the shallow 12 km depth produced an estimated instrumental intensity of only 4, suggesting the shaking was moderate rather than damaging.

A magnitude 5.7 earthquake struck 228 km east-southeast of Attu Station in the western Aleutians on 2 March 2026 — the third significant event along this arc within the same month. The Aleutian Islands extend in a 1,900 km arc from Alaska to Kamchatka and form one of the most active subduction zones on Earth. This event was notable for triggering a tsunami advisory: at 10 km depth, any M5.5+ submarine earthquake in this region automatically triggers an assessment protocol. The single felt report came from a remote monitoring station; the nearest population centre is hundreds of kilometres away.

A magnitude 5.7 earthquake struck 110 km east of Yamada in Iwate Prefecture on 4 March 2026, near the offshore area devastated by the 2011 Tohoku earthquake and tsunami. The Sanriku Coast of northeastern Honshu sits above the Japan Trench — a subduction zone that produced the catastrophic 2011 event (9.0) and continues to generate aftershocks and new earthquakes more than fifteen years later. With a relatively shallow depth of 10 km, this event could in principle generate localised strong shaking, though the USGS green alert indicated no significant impact expected for a 5.7 magnitude at this depth.

A magnitude 5.5 earthquake struck 2 km south-southeast of Rodotopi in northwestern Greece on 4 March 2026 — the same event that topped the month's significance rankings due to its yellow USGS alert status and 25 felt reports. Shallow at 10 km depth, the event generated an estimated maximum instrumental intensity of nearly 7 — enough for strong shaking to be felt across a wide area of Epirus and Albanian border regions. Greece has been struck by catastrophic earthquakes throughout its recorded history, from the 1953 Ionian Islands earthquake that killed 455 people to the 1999 Athens earthquake that killed 143.

A magnitude 5.5 earthquake struck south of the Kermadec Islands on 7 March 2026 — another routine reminder that this remote New Zealand territory lies at one of the most active submarine volcanic arcs in the world. The Kermadec Trench is the second deepest oceanic trench on Earth, plunging to 10,047 metres, and the subduction zone here generates numerous earthquakes every year. With no nearby population to feel the shaking, Kermadec earthquakes rarely make the news — but they contribute significantly to the planet's total seismic energy release and are monitored closely for tsunami potential.

A magnitude 5.4 earthquake struck 109 km east of Yamada, Iwate Prefecture — just minutes before the M5.7 event nearby, suggesting a closely linked aftershock sequence within the ongoing seismicity of the Japan Trench. The two events occurred 511 seconds apart and within a very similar geographic location, strongly indicating they represent separate ruptures on the same fault system or adjacent faults. Such sequences are common in the highly stressed subduction zone environment offshore Tohoku, where the accumulated strain from the 2011 megathrust continues to be released in discrete events years later.

A magnitude 6.0 earthquake struck 12 km west of the resort town of Anacapri on the island of Capri on 6 March 2026 — a reminder that Italy's picture-postcard coastlines sit above one of Europe's most volatile tectonic environments. The Campanian volcanic arc, home to Vesuvius, Stromboli, and the Campi Flegrei supervolcano, is underlain by the collision between the Eurasian and African plates. Thirteen people reported feeling this event; the USGS estimated a maximum instrumental intensity of only 3 on the modified Mercalli scale, suggesting the moderate depth of 10 km attenuated surface shaking.

A magnitude 5.9 earthquake struck 21 km northeast of Otobe in southern Hokkaido, Japan on 5 March 2026. Japan is one of the world's most seismically active nations — the country sits at the junction of four tectonic plates and experiences roughly 1,500 earthquakes strong enough to be felt each year. Southern Hokkaido sits above the Japan Trench, where the Pacific Plate subducts beneath the Okhotsk microplate at a rate of approximately 9 cm per year. At 4.2 km depth, this was a notably shallow event, maximising local shaking intensity even though the 5.9 magnitude produced no casualties.

A magnitude 5.9 earthquake struck 160 km south-southeast of the naval city of Vilyuchinsk on the Kamchatka Peninsula on 4 March 2026. Kamchatka is arguably the most seismically intense landmass on Earth — the peninsula sits directly above the convergence of the Pacific and North American plates, and the Kamchatka subduction zone has produced several of the largest earthquakes in recorded history, including the 1952 Kamchatka earthquake at magnitude 9.0. At 10 km depth and with no felt reports due to the remote location, this event was significant only geologically — a reminder that the Peninsula is never truly at rest.

A magnitude 5.9 earthquake struck 15 km west-southwest of the Tongan island of Niuatoputapu on 4 March 2026 — the same chain of islands devastated by the catastrophic Hunga Tonga–Hunga Ha'apai volcanic eruption and tsunami in January 2022. Tonga sits at the western edge of the Pacific Plate, where it subducts beneath the Australian Plate at the Tonga Trench — one of the deepest ocean trenches on Earth and one of the most seismically active subduction zones. Eight people reported feeling this event; the shallow 12 km depth produced an estimated instrumental intensity of only 4, suggesting the shaking was moderate rather than damaging.

A magnitude 5.7 earthquake struck 228 km east-southeast of Attu Station in the western Aleutians on 2 March 2026 — the third significant event along this arc within the same month. The Aleutian Islands extend in a 1,900 km arc from Alaska to Kamchatka and form one of the most active subduction zones on Earth. This event was notable for triggering a tsunami advisory: at 10 km depth, any M5.5+ submarine earthquake in this region automatically triggers an assessment protocol. The single felt report came from a remote monitoring station; the nearest population centre is hundreds of kilometres away.

A magnitude 5.7 earthquake struck 110 km east of Yamada in Iwate Prefecture on 4 March 2026, near the offshore area devastated by the 2011 Tohoku earthquake and tsunami. The Sanriku Coast of northeastern Honshu sits above the Japan Trench — a subduction zone that produced the catastrophic 2011 event (9.0) and continues to generate aftershocks and new earthquakes more than fifteen years later. With a relatively shallow depth of 10 km, this event could in principle generate localised strong shaking, though the USGS green alert indicated no significant impact expected for a 5.7 magnitude at this depth.

A magnitude 5.5 earthquake struck 2 km south-southeast of Rodotopi in northwestern Greece on 4 March 2026 — the same event that topped the month's significance rankings due to its yellow USGS alert status and 25 felt reports. Shallow at 10 km depth, the event generated an estimated maximum instrumental intensity of nearly 7 — enough for strong shaking to be felt across a wide area of Epirus and Albanian border regions. Greece has been struck by catastrophic earthquakes throughout its recorded history, from the 1953 Ionian Islands earthquake that killed 455 people to the 1999 Athens earthquake that killed 143.

A magnitude 5.5 earthquake struck south of the Kermadec Islands on 7 March 2026 — another routine reminder that this remote New Zealand territory lies at one of the most active submarine volcanic arcs in the world. The Kermadec Trench is the second deepest oceanic trench on Earth, plunging to 10,047 metres, and the subduction zone here generates numerous earthquakes every year. With no nearby population to feel the shaking, Kermadec earthquakes rarely make the news — but they contribute significantly to the planet's total seismic energy release and are monitored closely for tsunami potential.

A magnitude 5.4 earthquake struck 109 km east of Yamada, Iwate Prefecture — just minutes before the M5.7 event nearby, suggesting a closely linked aftershock sequence within the ongoing seismicity of the Japan Trench. The two events occurred 511 seconds apart and within a very similar geographic location, strongly indicating they represent separate ruptures on the same fault system or adjacent faults. Such sequences are common in the highly stressed subduction zone environment offshore Tohoku, where the accumulated strain from the 2011 megathrust continues to be released in discrete events years later.