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A lava cone is a type of volcano composed primarily of viscous lava flows. The volcanic cone can contain a convex profile due to the flank flows of viscous lava.
| | This article needs additional citations for verification .(June 2020) |
A lava cone is a type of volcano composed primarily of viscous lava flows. The volcanic cone can contain a convex profile due to the flank flows of viscous lava.
Lava cones are nearly unique to Bougainville Island in Papua New Guinea, within the Melanesia subregion of Oceania.
However, an unnamed group of seven lava cones is located in the Obul-Samarask upland of southern Georgia, in Western Asia. The cones are early Pleistocene to Holocene in age. Many of the craters have a well-preserved morphology. The tallest is 3,400 metres (11,200 ft). [1]
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.
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica, with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as 15 km (9.3 mi).
The Ring of Fire is a region around much of the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur. The Ring of Fire is a horseshoe-shaped belt about 40,000 km (25,000 mi) long and up to about 500 km (310 mi) wide.
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form.
Karkar Island is an oval-shaped volcanic island located in the Bismarck Sea, about 30 kilometres off the north coast of mainland Papua New Guinea in Madang Province, from which it is separated by the Isumrud Strait. The island is about 25 km in length and 19 km in width. In the centre is an active volcano with two nested calderas.
Langila is one of the most active volcanoes of New Britain, Papua New Guinea. It consists of four overlapping volcanic cones on the eastern flank of an older extinct volcano, Talawe. Talawe is the largest volcano in Cape Gloucester. There have been dozens of recorded eruptions since the 19th century from three separate volcanic craters at the summit of Langila. The most recent eruptive cycle of Langila began in August 2006 and continued into early 2007. Volcanic activity at Langila consists of Strombo-Vulcanian and Vulcanian eruptions and lava flows. Langila is one of the most active volcanoes in the Bismark archipelago. The smallest crater is crater number 3.
A complex volcano, also called a compound volcano or a volcanic complex, is a mixed landform consisting of related volcanic centers and their associated lava flows and pyroclastic rock. They may form due to changes in eruptive habit or in the location of the principal vent area on a particular volcano. Stratovolcanoes can also form a large caldera that gets filled in by a lava dome, or else multiple small cinder cones, lava domes and craters may develop on the caldera's rim.
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.
Loloru is a pyroclastic shield volcano located in the southern region of Bougainville Island, within the Autonomous Region of Bougainville of northeastern Papua New Guinea.
Tore is a volcano located in the northern part of the island of Bougainville, Papua New Guinea. Violent Pleistocene eruptions produced two ignimbrite fans stretching west to the coast, and a 6 km by 9 km caldera. A post-caldera lava cone on the caldera's southern rim is the source of lava flows. Well-preserved features suggests a recent date for this cone and a nearby ash cone.
The Itcha Range, also known as the Itchas, is a small isolated mountain range in the West-Central Interior of British Columbia, Canada. It is located 40 km (25 mi) northeast of the community of Anahim Lake. With a maximum elevation of 2,375 m (7,792 ft), it is the lowest of three mountain ranges on the Chilcotin Plateau extending east from the Coast Mountains. Two mountains are named in the Itcha Range; Mount Downton and Itcha Mountain. A large provincial park surrounds the Itcha Range and other features in its vicinity. More than 15 animal species are known to exist in the Itcha Range area, as well as a grassland community that is limited only to this location of British Columbia. The Itcha Range is within territory which has been occupied by aboriginal peoples for millennia. This area has a relatively dry environment compared to the Coast Mountains in the west.
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.
In volcanology, a pyroclastic shield or ignimbrite shield is an uncommon type of shield volcano. Unlike most shield volcanoes, pyroclastic shields are formed mostly of pyroclastic and highly explosive eruptions rather than relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. They typically display low-angle flank slopes and often have a central caldera caused by large eruptions. Lava is commonly extruded after explosive activity has ended. The paucity of associated Plinian fall deposits indicates that pyroclastic shields are characterized by low Plinian columns.
The Sulu Range is a small volcanic mountain range on the Papua New Guinean island of New Britain. It consists of a group of partially overlapping small stratovolcanoes and lava domes, with the highest point being 610 m (2,000 ft) Mount Malopu at the southwestern end of the range. Kaiamu, a maar at the northwestern end of the Sulu Range, forms a peninsula with a small lake extending about 1 km (0.62 mi) into Bangula Bay. Other volcanoes in the range include Mount Ululu, Mount Ruckenberg, Mount Talutu and Mount Ubia.
The Volcanic Seven Summits are the highest volcanoes on each of the seven continents, just as the Seven Summits are the highest peaks on each of the seven continents. Summiting all seven is regarded as a mountaineering challenge, first postulated as such in 1999.
The Mount Edziza volcanic complex is a large and potentially active north-south trending complex volcano in Stikine Country, northwestern British Columbia, Canada, located 38 kilometres (24 mi) southeast of the small community of Telegraph Creek. It occupies the southeastern portion of the Tahltan Highland, an upland area of plateau and lower mountain ranges, lying east of the Boundary Ranges and south of the Inklin River, which is the east fork of the Taku River. As a volcanic complex, it consists of many types of volcanoes, including shield volcanoes, calderas, lava domes, stratovolcanoes, and cinder cones.
Lava is magma once it has been expelled from the interior of a terrestrial planet or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or undersea, usually at temperatures from 800 to 1,200 °C. The volcanic rock resulting from subsequent cooling is also often called lava.
The Andagua volcanic field is a volcanic field in southern Peru which includes a number of cinder cones, lava domes and lava flows which have filled the Andagua Valley. The volcanic field is part of a larger volcanic province that clusters around the Colca River and is mostly of Pleistocene age, although the Andagua sector also features volcanic cones with historical activity, with the last eruption about 370 years ago. Eruptions were mostly effusive, generating lava flows, cones and small eruption columns. Future eruptions are possible, and there is ongoing fumarolic activity. Volcanic activity in the field has flooded the Andahua valley with lava flows, damming local watersheds in the Laguna de Chachas, Laguna Mamacocha and Laguna Pumajallo lakes and burying the course of the Andagua River. The Andahua valley segment of the larger volcanic province was declared a geopark in 2015.
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