A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
Vulcano or Vulcan is a small volcanic island belonging to Italy in the Tyrrhenian Sea, about 20 km (12 mi) north of Sicily and located at the southernmost end of the seven Aeolian Islands. The island is known for its volcanic activity and contains several volcanic calderas, including one of the four active volcanoes in Italy that are not submarine. The English word "volcano", and its equivalent in several European languages, derives from the name of this island, which derives from the Roman belief that the tiny island was the chimney of Vulcan, the Roman god of fire. In November 2021, 150 people were evacuated from the island's harbour area due to increased volcanic activity and gases; an amber alert had been issued in October 2021 after several significant changes in the volcano's parameters.
New Britain is the largest island in the Bismarck Archipelago, part of the Islands Region of Papua New Guinea. It is separated from New Guinea by a northwest corner of the Solomon Sea and from New Ireland by St. George's Channel. The main towns of New Britain are Rabaul/Kokopo and Kimbe. The island is roughly the size of Taiwan. While the island was part of German New Guinea, it was named Neupommern . In common with most of the Bismarcks it was largely formed by volcanic processes, and has active volcanoes including Ulawun, Langila, the Garbuna Group, the Sulu Range, and the volcanoes Tavurvur and Vulcan of the Rabaul caldera. A major eruption of Tavurvur in 1994 destroyed the East New Britain provincial capital of Rabaul. Most of the town still lies under metres of ash, and the capital has been moved to nearby Kokopo.
The Ring of Fire is a tectonic belt, about 40,000 km (25,000 mi) long and up to about 500 km (310 mi) wide, which circumscribes the Pacific Ocean. It contains between 750 and 915 volcanoes, around two-thirds of the world total, and 90% of the world's earthquakes, including 81% of its largest, take place within the belt.
Rabaul is a township in the East New Britain province of Papua New Guinea, on the island of New Britain. It lies about 600 kilometres to the east of the island of New Guinea. Rabaul was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash from a volcanic eruption in its harbor. During the eruption, ash was sent thousands of metres into the air, and the subsequent rain of ash caused 80% of the buildings in Rabaul to collapse. After the eruption the capital was moved to Kokopo, about 20 kilometres (12 mi) away. Rabaul is continually threatened by volcanic activity, because it is on the edge of the Rabaul caldera, a flooded caldera of a large pyroclastic shield.
A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, occurs when magma heats ground water or surface water. The extreme temperature of the magma causes near-instantaneous evaporation of water to steam, resulting in an explosion of steam, water, ash, rock, and volcanic bombs. At Mount St. Helens in Washington state, hundreds of steam explosions preceded the 1980 Plinian eruption of the volcano. A less intense geothermal event may result in a mud volcano.
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption. A maar characteristically fills with water to form a relatively shallow crater lake, which may also be called a maar.
Manam, known locally as Manam Motu, is an island located in the Bismarck Sea across the Stephan Strait from Yawar on the northeast coast of mainland Papua New Guinea's Bogia District. The island is 10 kilometers wide, and was created by the activity of the Manam Volcano, one of the country’s most active. It was evacuated in 2004 and its residents resettled elsewhere in Papua New Guinea, but many have begun to return despite concerns of future volcanic activity. Manam is erupting again as of May 2022.
Cerro Negro is an active volcano in the Cordillera de los Maribios mountain range in Nicaragua, about 10 km (6.2 mi) from the village of Malpaisillo. It is a very new volcano, the youngest in Central America, having first appeared in April 1850. It consists of a gravelly basaltic cinder cone, which contrasts greatly with the surrounding verdant hillsides, and gives rise to its name, which means Black Hill. Cerro Negro has erupted frequently since its first eruption. One unusual aspect of several eruptions has been the emission of ash from the top of the cone, while lava erupts from fractures at the base.
Cerro Azul, sometimes referred to as Quizapu, is an active stratovolcano in the Maule Region of central Chile, immediately south of Descabezado Grande. Part of the South Volcanic Zone of the Andes, its summit is 3,788 meters (12,428 ft) above sea level, and is capped by a summit crater that is 500 meters (1,600 ft) wide and opens to the north. Beneath the summit, the volcano features numerous scoria cones and flank vents.
A Vulcanian eruption is a type of volcanic eruption characterized by a dense cloud of ash-laden gas exploding from the crater and rising high above the peak. They usually commence with phreatomagmatic eruptions which can be extremely noisy due to the rising magma heating water in the ground. This is usually followed by the explosive clearing of the vent and the eruption column is dirty grey to black as old weathered rocks are blasted out of the vent. As the vent clears, further ash clouds become grey-white and creamy in colour, with convolutions of the ash similar to those of Plinian eruptions.
Karymsky is an active stratovolcano on the Kamchatka Peninsula, Russia. It and Shiveluch are Kamchatka's largest, most active and most continuously erupting volcanoes, as well as one of the most active on the planet.
Long Island is a populated volcanic island in Madang Province, Papua New Guinea. It is located north of the island of New Guinea, separated from it by the Vitiaz Strait. The island's interior contains a 360m deep freshwater volcanic crater lake and within that lake exists an even smaller island known as Motmot island. During the late 17th or early 18th century virtually all of the biota on the island was destroyed and has subsequently provided scientists a unique opportunity to study recolonization efforts by plants, animals, and humans. The vast majority of the buildings on the island are constructed using vernacular architecture.
Bagana is an active volcanic cone located in the centre of the island of Bougainville, Papua New Guinea, the largest island of the Solomon group. It is the most active volcano in the country, occupying a remote portion of central Bougainville Island. It is one of Melanesia's youngest and most active volcanoes.
Billy Mitchell is a pyroclastic shield in the central part of the island of Bougainville, just north-east of the Bagana Volcano in Papua New Guinea. It is a small pyroclastic shield truncated by a 2 km wide caldera filled by a crater lake. It is named after Billy Mitchell, a 20th-century United States Army general who is regarded as the father of the United States Air Force.
Several types of volcanic eruptions—during which lava, tephra, and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series.
Kadovar is a volcanic island in Papua New Guinea northeast of the much larger island of New Guinea. The volcano erupted in January 2018 and the eruption is ongoing as of 2023, although the activity level is generally considered to be low. There were some heightened thermal phenomena in 1976.
On the morning of March 13, 1888, an explosion took place on Ritter Island, a small volcanic island in the Bismarck and Solomon Seas, between New Britain and Umboi Island. The explosion resulted in the collapse of most of the island and generated a tsunami with runups of up to 15 meters (49 ft) that caused damage more than 700 kilometers (430 mi) away and killed anywhere between 500 and 3,000 on neighbouring islands, including scientists and explorers. This event is the largest volcanic island sector collapse in recent history.
In early January 1951, a series of minor explosions and earthquakes rocked Mount Lamington, a volcano in Oro Province, Territory of Papua and New Guinea. Prior to the eruption, Mount Lamington was not recognized as a volcano due to the absence of historically-recorded eruptions and dense vegetation cover. From January 15, volcanic activity intensified, and tall eruption plumes were generated. The largest eruption occurred on the morning of January 21 when a thick black plume of ash rose 50,000 feet (15,000 m) into the atmosphere. The eruption collapsed a lava dome and produced a lethal pyroclastic flow that killed 2,942 people. In the years after the eruption, new lava domes formed and collapsed in succession. Activity persisted until July 1956. The eruption is the deadliest natural disaster in Australian history, as the region was under the rule of the Government of Australia.
Bam, also known as Biem, is a small volcanic island off the coast of Papua New Guinea, 40 km north northeast of the Sepik river mouth. It represents the southernmost island of the Schouten Islands. The northern coast of the island is inhabited by a village and coconut groves. Much of the island is forested, except along its south flank. As of 2018, the island has a population of approximately 3,000 people.
