Volcanoes of the world

Known forA flank collapse that made a tsunami with no earthquake

The child of Krakatoa, which grew out of the 1883 caldera from 1927. In December 2018 its southwest flank collapsed into the Sunda Strait and generated a tsunami that killed over 400 people with no seismic warning at all, because there was no earthquake to detect.

Settingyoung cone · caldera remnant · flank instability

For the examTsunami warning systems are built around seismometers; a volcanic flank collapse produces no precursory earthquake, which is the gap the 2018 event exposed.

Known forIndia's only active volcano

India’s only confirmed active volcano, in the Andaman Sea on the Burma–Sunda arc.

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For the examIndia’s only active volcano. Narcondam, to its north, is dormant. Both are Andaman & Nicobar territory.

Known forA caldera with half a million people inside it

A 13 km caldera west of Naples with about half a million people living inside it. Its floor rises and falls — bradyseism — and since 2005 it has been inflating again, with the strongest earthquakes in forty years recorded in 2023–24 and the alert level raised.

Settingcaldera · bradyseism · densely populated

For the examBradyseism is the slow ground uplift and subsidence over a magma chamber. Campi Flegrei is considered a higher risk than Vesuvius beside it because of what sits on top of it.

Known forOne of the highest active volcanoes, almost on the Equator

One of the highest active volcanoes in the world, in the Ecuadorian Andes almost on the Equator.

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Known forThe 2021 Canary eruption, and a tsunami claim that did not hold

The ridge on La Palma in the Canaries that erupted for 85 days in 2021, destroying about 3,000 buildings and adding new land to the coast where lava met the sea. A much-publicised hypothesis that its western flank could collapse and send a mega-tsunami across the Atlantic is not supported by most subsequent work.

Settingrift-zone volcano · hotspot island · basaltic

Known forA century-old lava lake, on an opening ocean

A shield volcano in the Danakil with one of the very few long-lived lava lakes on earth, active since at least 1906. It sits on the Afar spreading centre, where an ocean is opening on land.

Settingshield volcano · lava lake · rift

Known forThe small eruption that closed European airspace

Its 2010 ash plume closed European airspace for a week — a small eruption with an outsized economic effect.

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Known forReykjanes awake after eight centuries

The volcano that reawoke the Reykjanes peninsula in March 2021 after roughly 800 years of quiet, beginning an eruptive episode that has continued in pulses. Fissures near Grindavík from late 2023 forced the town's evacuation and cut the road to the Blue Lagoon.

Settingfissure eruption · spreading ridge · effusive

For the examA fissure eruption on a divergent boundary — runny basalt, lava fountains, very little ash. The contrast with a subduction-zone volcano's explosive andesite is the point.

Known forIceland's most active, on a spreading ridge

One of Iceland’s most active, on the mid-Atlantic rift where the plates pull apart rather than collide.

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Known forThe eruption that put an ocean into the stratosphere

A submarine volcano on the Tonga arc whose January 2022 eruption was the most powerful recorded since Krakatoa. It generated a pressure wave that circled the earth several times, a tsunami felt across the Pacific, and injected roughly 150 million tonnes of water vapour into the stratosphere — more than any eruption ever measured, and enough to warm rather than cool the surface for a few years.

Settingsubmarine caldera · island arc · surtseyan

For the examUnusual because it warmed rather than cooled: sulphate aerosols cool, water vapour is a greenhouse gas. That inversion of the usual volcanic-climate story is what the stem uses.

Known forThe bigger volcano under the ice cap

A large caldera beneath the Mýrdalsjökull ice cap, historically far more powerful than Eyjafjallajökull beside it. An eruption under ice produces a jökulhlaup — a glacial outburst flood — which in Katla's case has repeatedly discharged more water than the Amazon for a few hours.

Settingsubglacial caldera · jökulhlaup source · explosive

For the examJökulhlaup is the hazard from subglacial volcanism, and it is a flood hazard rather than a lava one.

Known forAn intra-plate volcano, not a margin one

A shield volcano on the Hawaiian hotspot — an intra-plate volcano, not a plate-margin one, which is the point.

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For the examHotspot volcanism, not subduction. The Hawaiian chain records the plate moving over a fixed plume.

Known forThe 1883 eruption heard four thousand kilometres away

The 1883 eruption was heard 4,800 km away and dropped global temperatures for years. It stands in the Sunda Strait.

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For the examSunda Strait, Indonesia. Anak Krakatau is the child cone that grew in the caldera.

Known forThe 2021 eruption that emptied northern Saint Vincent

The volcano on Saint Vincent that erupted explosively in April 2021 after decades of quiet, blanketing the island in ash and forcing about 20,000 people from the northern third of it.

Settingstratovolcano · Lesser Antilles arc · explosive

Known forThe fissure eruption that starved two continents

A 27 km fissure that erupted for eight months in 1783–84, releasing an enormous volume of sulphur dioxide. The haze killed a fifth of Iceland's population and much of its livestock, caused crop failure across Europe, and is argued to have contributed to the conditions behind the French Revolution.

Settingfissure eruption · flood basalt · sulphurous haze

For the examA flood-basalt-style event in historical time — the closest analogue to what the Deccan Traps did, at a millionth of the scale.

Known forThe largest active volcano on earth by volume

The largest volcano on earth by volume, and the classic shield profile.

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Known forThe most symmetrical cone in the world

The most active volcano in the Philippines, and the classic textbook perfect cone.

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Known forIndonesia's most active, above two million people

Indonesia’s most active volcano, on Java, above Yogyakarta.

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Known forWhere pyroclastic flows were first understood

The volcano on Martinique whose 1902 eruption destroyed Saint-Pierre in minutes and killed about 30,000 people — the deadliest eruption of the 20th century. It gave volcanology the term nuée ardente, and the modern understanding of pyroclastic density currents.

Settinglava-dome volcano · pyroclastic flows · Lesser Antilles arc

For the examPeléan eruption is the named style. The Lesser Antilles arc exists because the Atlantic subducts beneath the Caribbean Plate.

Known forA caldera with towns and railways inside it

One of the largest calderas in the world, 25 km across on Kyushu, with towns and railways inside it and an active cone at its centre. Its caldera formed in four enormous eruptions, the last about 90,000 years ago.

Settingcaldera · active central cone · Japanese arc

Known forWest Africa's volcano, and one of the wettest slopes on earth

West Africa's highest peak and its most active volcano, standing where the Cameroon Volcanic Line meets the coast. Its south-west flank is one of the wettest places on earth, receiving over 10,000 mm a year as the monsoon runs straight into it off the Gulf of Guinea.

Settingshield-stratovolcano · volcanic line · ultra-wet

For the examThe Cameroon Volcanic Line runs from the Gulf of Guinea islands inland — an intraplate chain that does not fit the simple hotspot model. Lake Nyos on it killed 1,700 people by limnic eruption in 1986.

Known forThe southernmost active volcano on earth

The southernmost active volcano on earth, on Ross Island, Antarctica — also with a lava lake.

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Known forEurope's highest and most continuously active

Europe’s most active volcano, on Sicily, above the Africa–Eurasia convergence.

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Known forWhere three plates meet, and a national symbol

A stratovolcano and the highest point in Japan, on the junction of three tectonic plates.

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Known forThe Millennium Eruption, and a border-straddling crater lake

A caldera volcano on the China–North Korea border, holding the deep crater lake Heaven Lake. Its Millennium Eruption around 946 CE was one of the largest of the last two thousand years. It is a national symbol in both Koreas, and one of the very few subjects on which North Korean and Western scientists have collaborated.

Settingcaldera · crater lake · intraplate

Known forThe lahar hazard above Seattle

The most heavily glaciated peak in the contiguous United States, standing over the Seattle–Tacoma lowland. Its danger is not lava but lahars: past collapses have sent mudflows all the way to Puget Sound, and about 90,000 people now live on those deposits.

Settingglaciated stratovolcano · Cascade arc · lahar hazard

For the examThe Cascade arc sits above the subducting Juan de Fuca plate — a small plate, which is why the arc is short. Rainier is a Decade Volcano for its hazard-to-population ratio.

Known forA crater lake that produces lahars

The highest point of New Zealand's North Island, with a crater lake on its summit. When the lake is displaced by eruption it produces a lahar — a torrent of water and volcanic debris — and the 1953 Tangiwai lahar destroyed a rail bridge minutes before an express crossed it, killing 151 people.

Settingstratovolcano · crater lake · lahar hazard

For the examA lahar is the volcanic hazard that kills furthest from the vent and long after the eruption. Nevado del Ruiz is the deadliest example.

Known for1980, and the type example of a flank collapse

The 1980 lateral blast removed the north face and 400 m of summit — the type example of a flank collapse.

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Known forIndia's dormant second, in the Andaman arc

A dormant volcano in the Andaman Sea, and the only home of the Narcondam hornbill.

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Known forThe small eruption that killed 23,000

A glacier-capped Andean volcano whose modest 1985 eruption melted part of its ice cap and sent lahars down the valleys, burying the town of Armero and killing about 23,000 people. It is the deadliest lahar in recorded history and the reason volcanic hazard mapping became standard practice.

Settingglaciated stratovolcano · lahar hazard · Andean arc

For the examEruption size does not predict death toll — ice cap plus steep valleys plus a town on an old lahar deposit does. Armero is the standard disaster-management case.

Known forThe busier half of the Virunga pair

Africa's most frequently erupting volcano, beside Nyiragongo in the Virunga chain on the western branch of the East African Rift. Between them they emit a large share of the world's volcanic sulphur dioxide.

Settingshield volcano · rift · very fluid lava

Known forA persistent lava lake above a city of two million

One of very few volcanoes with a persistent lava lake, on the East African Rift above Goma.

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Known forThe one volcano erupting carbonate lava

The only volcano on earth currently erupting natrocarbonatite — a lava so cool, around 500°C, and so unlike silicate magma that it flows like black oil and turns white within hours of contact with air. It stands on the East African Rift beside the Ngorongoro highlands.

Settingcarbonatite volcano · rift · unique chemistry

For the examOrdinary lava is silicate at 800–1,200°C. Carbonatite is the exception and this is the only active example, which is why it is asked.

Known for1991, and half a degree off the whole planet

Its 1991 eruption — the second largest of the 20th century — cooled the planet by about 0.5°C.

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Known forThe smoking mountain above Mexico City

An active stratovolcano within sight of Mexico City.

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Known forIt erupts hundreds of times a year, beside a city

Erupts hundreds of times a year above the city of Kagoshima, Japan.

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Known forJava's highest, erupting several times a day

Java's highest peak and one of its most persistently active volcanoes, erupting several times a day for decades. Pyroclastic flows and lahars down its southern flank killed dozens in December 2021 and again in 2022.

Settingstratovolcano · Sunda arc · persistent activity

Known forThe eruption that abandoned a capital city

The volcano that destroyed Plymouth, Montserrat's capital, from 1995 — burying it in ash and pyroclastic flows and forcing most of the island's population to leave permanently. Over half the island remains an exclusion zone.

Settinglava-dome volcano · pyroclastic flows · Lesser Antilles arc

For the examLava-dome collapse generates pyroclastic flows — the same mechanism as Mont Pelée. Plymouth is the only abandoned capital of its kind.

Known forThe lighthouse of the Mediterranean

In near-continuous eruption for two thousand years — the "lighthouse of the Mediterranean", and the type example of Strombolian activity.

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Known forA volcano in a lake in a caldera

A volcano within a lake within a caldera — the standard example of a nested volcanic landform.

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Known for1815, and the year without a summer

The largest eruption in recorded history, 1815, and the cause of the "year without a summer" in 1816.

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Known forThe caldera that disrupted Minoan Crete

A caldera in the Aegean formed by an eruption around 1600 BCE, one of the largest of the Holocene. Its ash and tsunami disrupted Minoan Crete, and the flooded caldera is one of the clearest examples of the landform anywhere. A seismic swarm beneath it in early 2025 prompted a state of emergency.

Settingflooded caldera · Hellenic arc · explosive

For the examIt sits on the Hellenic volcanic arc above the subduction of Africa beneath Europe — the same margin as the Hellenic Trench.

Known forPompeii, and the most dangerous volcano in Europe

The eruption of AD 79 buried Pompeii and Herculaneum. A somma volcano — a cone inside an older caldera rim.

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Known forThe 2019 eruption that changed volcano tourism

An andesitic island volcano in the Bay of Plenty that erupted without warning in December 2019 while tourists were in the crater, killing 22. The case led to prosecutions and reshaped how volcanic tourism is regulated worldwide.

Settingisland stratovolcano · hydrothermal · sudden

For the examA phreatic eruption — steam-driven, with no fresh magma reaching the surface — which is why it gave almost no precursory warning.