Rabaul and Tavui are partially submerged calderas, while Karkar have massive summit calderas measuring over 5 kilometers across.
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Police went to the Cabool, Missouri, trailer home of 24 -year-old Calderas after Steinfeld's family said Calderas, Vrba and Schauer, both 18, were the last people to be with the teen.
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Calderas, fumaroles, volcanic lakes and thermal springs dot the landscape.
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Their analysis revealed surprising insights into calderas and how they emerge.
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"One would think that calderas don't collapse like pistons," he said.
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Calderas are relatively rare geologic phenomena, occurring only a handful of times each century.
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Some of these volcanoes are spectacular calderas that have been the source of massive eruptions.
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For example, geologists aren't entirely sure if calderas are triggered by volcanic eruptions, or vice versa.
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Schauer and Calderas told police Vrba claimed he stabbed the victim's genitals multiple times and gouged her eyes out.
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Above that rise the three different little camera volcanoes, and above each of those the little calderas of the lenses.
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The history of this sleeping colossus includes two massive eruptions, 39,000 and 15,000 years ago, that left deep calderas in the landscape.
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When the deputy subsequently interviewed Vrba, he allegedly "admitted that he killed Steinfield and burned his body" in the yard at Calderas' home.
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A cone volcano is the most immediately recognizable mountain-shaped variety, as opposed to shield volcanoes or calderas, which are flatter in shape.
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Retrocedió y observó a los monjes hacer su recorrido desde los edificios de las calderas hasta la calera y la planta de celulosa.
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Retrocedió y observó a los monjes hacer su recorrido desde los edificios de las calderas hasta la calera y la planta de celulosa.
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Schauer and Vrba's statements contradicted that, and they stated Calderas did want Steinfield killed, and even mentioned it several days prior to Steinfield's death.
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The final images are revelatory works of landscape photography in which seemingly lifeless concrete wastelands are transformed into thrilling canyons, calderas, plateaus, and peaks.
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She'd been living with Calderas— whom she was dating — in a trailer in Cabool when she was reported missing by her family on Sept.
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Calderas: These are formed when a volcano erupts with such force that it causes the summit to collapse into the partially empty magma chamber below.
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Even in San Jose Calderas, several miles north of the eruption, maize and peach crops were ruined by six inches of hot ash and rocks.
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A cone volcano is the most immediately recognizable mountain-shaped variety, as opposed to shield volcanoes or calderas which are far more flat in shape.
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A public defender, Michael Jacobs, who is listed in court documents as an attorney for Vrba, Schauer and Calderas, could not immediately be reached by PEOPLE.
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No less than four major calderas sit in the Taupo Volcanic Zone (TVZ) that stretches from White Island in the north to Ruapehu in the south.
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The valley was wide and flat, pocked with gaping calderas that blew enormous plumes of steam into the air, like sideways clouds drifting into the sky.
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Calderas also allegedly told the deputy that she helped drag the body outside and went with Schauer to buy items used to burn it, the deputy wrote.
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Over the course of six months, the ice-filled land mass above it sunk down even further, creating a massive bowl-like depression that is characteristic of calderas.
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Vrba and three others — Vrba's girlfriend, Isis Schauer, 18; Briana Calderas, 24; and James T. Grigsby, around age 25, according to police — were arraigned Monday in the case.
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Nabro was obviously a volcano with a colorful past as images taken prior (see below) to the June 2011 eruption show multiple calderas and smaller craters and cinder cones.
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The deputy then interviewed Calderas, who allegedly "admitted that Steinfield was killed at her residence, and that she helped Vrba burn the body," according to the probable cause statement.
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Authorities have charged two men and two women in connection with Steinfeld's death: Briana Calderas, 24, Andrew Vrba, 18, and Isis Schauer, 18, were charged with first-degree murder.
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The suspect allegedly said he stabbed Steinfield in the living room, and that after Steinfeld was dead, the body was wrapped up and taken outside by Vrba, Schauer and Calderas.
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Out of those collapses we get calderas, the depressions formed when all the stuff that was underground goes missing and the Earth's crust slumps down to fill some of the space.
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" According to the probable cause statement, Steinfield was last seen with Vrba, Schauer and Calderas, all of whom Steinfield's family had approached for answers and "believed they were being lied to.
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It is quieter in San Jose Calderas, about 40 miles west of Guatemala City, where Delia Junech lives with her six children, two of whom were born in the United States.
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She stressed that the finding does not mean there will be another large eruption anytime soon and that calderas have a spectrum of activity and hazards that require further research to understand.
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Texas County authorities have charged Andrew Vrba, Isis Schauer and Briana Calderas with the first-degree murder of 17-year-old Ally Lee Steinfeld, whose family had reported her missing earlier this month.
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"Calderas occur around the world and the more we know about the differences and similarities," she said, "the more we can understand the hazards and how to prepare for potential eruptions in the future."
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Based on 2-meter resolution images captured by commercial satellites and fed into a supercomputer at the University of Illinois, the maps show Alaska's rugged mountains, volcanic calderas, winding rivers, and glaciers in greater detail than ever before.
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Dr. Rowland said that while no Martian (or, for that matter, lunar) volcanoes are active, Hawaii's volcanoes are useful to scientists because they have newly formed faults, craters, calderas and other features that can be studied up close.
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The presence of two calderas suggests that Campi Flegrei has probably completed at least one cycle, and if this pattern is indeed real, then the chemistry hints that "we are potentially at the start of a new cycle," Dr. Forni said.
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Many who live on the slopes of the Fuego and Acatenango volcanoes earned money as guides, porters or cooks for visitors, said Elder Dary Soy López, a guide with Asociación Aprode in San Jose Calderas, a town at the foot of Acatenango.
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Lurking beneath Yellowstone National Park is a massive underground reservoir of magma, capped by…Read more ReadInsights gleaned over the course of this research project will undoubtedly help scientists understand other calderas, including the ominous kettle located at Yellowstone in the United States, or those in the Andes region.
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It's a little bigger than the U.S. state of Arizona, but its islands are spread out over several hundred miles and because they're so pristine, with everything from diverse marine life to unique and fascinating calderas, its appeal to tourists is as clear as the waters around it.
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Cerro Blanco lies at an elevation of and consists of four nested calderas with discontinuous borders, fallout deposits, lava domes and pyroclastic deposits. The two inconspicuous El Niño and Pie de San Buenaventura calderas are nested in the northern part of the complex and form a wide depression. Only their northern margins are recognizable in satellite images; their southern parts are filled with block and ash flows from the southern calderas. The southern calderas are the Robledo and Cerro Blanco calderas, which form a southeast-northwest trending pair.
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The collapse feature is an analog of Earth's volcanic calderas.
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Tschima da Flix is a mountain of the Albula Alps, located between Piz Calderas and Piz d'Agnel, in the canton of Graubünden. On the northern side of the mountain lies a glacier named Vadret da Calderas.
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Polygenetic volcanoes include stratovolcanoes, complex volcanoes, somma volcanoes, shield volcanoes and calderas.
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As a result, the magma is much less viscous than the magma of a rhyolitic volcano, and the magma chamber is drained by large lava flows rather than by explosive events. The resulting calderas are also known as subsidence calderas and can form more gradually than explosive calderas. For instance, the caldera atop Fernandina Island collapsed in 1968 when parts of the caldera floor dropped .
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Intrusion rates range from and resulted in plutons of volume beneath the calderas.
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Nemo Peak has formed several calderas. Two older ones reach diameters of and overlap each other, with an average elevation of the floor of . The Sovetskii ridge limits these calderas to the east. A pre-Nemo volcano is known as Mednyi.
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Sekincau is a volcano with two calderas, Belirang (2 km wide) and Balak (2.5 km wide), located in the south of Sumatra, Indonesia. A 300 m wide of crater is found at the summit. Fumarole activities are found at the foot of calderas.
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Most calderas are associated with fault systems that may play a role in caldera formation.
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The area's calderas are poorly understood and some may yet be undiscovered. Some calderas were subject to comprehensive research. Research in this area is physically and logistically difficult. Neodym, lead and boron isotope analysis has been used to determine the origin of eruption products.
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Glaciers were present during the ice ages, leaving glacial calderas and small glacial lakes, such as the Bistra Lake.
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Calderas form on top of Tarso Toussidé and Emi Koussi, and the lava domes Ehi Sosso and Ehi Mousgou appeared. Finally, in the sixth phase, Pic Toussidé formed on the western rim of several pre-Trou au Natron calderas, along with new lava flows, including Timi on the northern slope of Tarso Toussidé. With scarce time for erosion, these lava flows have a dark, youthful appearance. The Trou au Natron and Doon Kidimi craters have formed even more recently, with the former dissecting the earlier Toussidé calderas.
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Alternative interpretations consider the Pie de San Buenaventura, Robledo and Cerro Blanco calderas as one caldera, that the Robledo and Cerro Blanco calderas are one system or envisage the existence of only three calderas. The Cerro Blanco caldera is about \- wide and its walls are up to high. They are formed by ignimbrite breccia, ignimbrites and lava domes cut by the caldera margins. The caldera floor is almost entirely covered by block-and-ash flows, apart from an area where hydrothermal activity has left white sinter deposits.
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Volcán Irazú, Costa Rica Volcanic lakes are lakes that occupy either local depressions, e.g. craters and maars or larger basins, e.g. calderas, created by volcanism. Crater lakes are formed in volcanic craters and calderas, which fill up with precipitation more rapidly than they empty via either evaporation, groundwater discharge, or combination of both.
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Bulletin of Volcanology. 33:566–578 aphyric basalt, olivine basalt and a third basalt which contains large phenocrysts of olivine, augite and plagioclase. These different rock types provide evidence for different eruptive phases. Kone is unusual due to the number of calderas in the Volcanic Complex, Fentale contains only one calderas in comparison.
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Active during the Cretaceous, it is a large caldera. Post-collapse activity generated subsidiary calderas inside the older main caldera.
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The caldera of Lake Toba, with a resurgent dome, forming Samosir Island. In geology, a resurgent dome is a dome formed by swelling or rising of a caldera floor due to movement in the magma chamber beneath it. Unlike a lava dome, a resurgent dome is not formed by the extrusion of highly viscous lava onto the surface, but rather by the uplift and deformation of the surface itself by magma movement underground. Resurgent domes are typically found near the center of very large open calderas such as Yellowstone Caldera or Valles Caldera, and in turn such calderas are often referred to as "resurgent-type" calderas to distinguish them from the more common (but much smaller) calderas found on shield volcanoes and stratovolcanoes.
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The two nested calderas share the same rim on their western sides, but the older Island Park Caldera is much larger and more oval and extends well into Yellowstone National Park.Newhall and Daniel Dzurisin, 1988, "Historical Unrest at Large Calderas of the World", U.S. Geological Survey Bulletin 1855. The Island Park Caldera is sometimes referred to as the First Phase Yellowstone Caldera or the Huckleberry Ridge Caldera. To the southwest of the caldera lies the Snake River Plain, which was formed by a succession of older calderas marking the path of the Yellowstone hotspot.
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Yellowstone sits on top of four overlapping calderas. (US NPS) Volcanism at Yellowstone is relatively recent, with calderas that were created during large eruptions that took place 2.1 million, 1.3 million, and 630,000 years ago. The calderas lie over the Yellowstone hotspot under the Yellowstone Plateau where light and hot magma (molten rock) from the mantle rises toward the surface. The hotspot appears to move across terrain in the east-northeast direction, but in fact the hotspot is much deeper than terrain and remains stationary while the North American Plate moves west-southwest over it.
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Tupan Patera, an example of a volcanic depression Intra-patera eruptions occur within volcanic depressions known as paterae, which generally have flat floors bounded by steep walls. Paterae resemble terrestrial calderas, but it is unknown whether they form when an empty magma chamber collapses, like their terrestrial cousins. One hypothesis suggests that they are produced through the exhumation of volcanic sills, with the overlying material either being blasted out or integrated into the sill. Some paterae display evidence for multiple collapses, similar to the calderas atop Olympus Mons on Mars or Kīlauea on Earth, suggesting that they may occasionally form like volcanic calderas.
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Calderas form if a volcano explodes or collapses, following the emptying of the magma chamber below, and further spreading can fracture the volcanoes as well.
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Passaconaway was transferred to the Dominican Republic in September 1976 as patrol vessel Calderas (P209). , the ship remained in active service with the Dominican Navy.
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Yellowstone sits on top of three overlapping calderas. The Yellowstone Plateau volcanic field is composed of four adjacent calderas. West Thumb Lake is itself formed by a smaller caldera which erupted 174,000 years ago. (See Yellowstone Caldera map.) The Henry's Fork Caldera in Idaho was formed in an eruption of more than 1.3 million years ago, and is the source of the Mesa Falls Tuff.
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Calderas are volcanic depressions formed after an erupted volcano collapses. Resurgent calderas can refill with an eruption of rhyolitic magma to form the extrusive rock rhyolite like the Yellowstone Caldera. Submarine volcanoes erupt on the ocean floor and produce the extrusive rock pumice. Pumice is a light-weight, glass with a vesicular texture that differs from scoria in its silicic composition and therefore floats.
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Caldera formation under water. Some calderas are known to host rich ore deposits. Metal-rich fluids can circulate through the caldera, forming hydrothermal ore deposits of metals such as lead, silver, gold, mercury, lithium and uranium. One of the world's best-preserved mineralized calderas is the Sturgeon Lake Caldera in northwestern Ontario, Canada, which formed during the Neoarchean era about 2.7 billion years ago.
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Such faulting is believed to be the surface manifestation of a deeper shear zone. Progression of ages of rhyolitic (silicic) lavas and calderas from McDermitt Caldera to Newberry and Yellowstone calderas (red circles: MC, NC, & YC). Numbers are ages in millions of years. KBML - Klamath–Blue Mountains Lineament, HLP - High Lava Plains, EDZ - Eugene—Denio Zone, BFZ - Brothers Fault Zone, SMF - Steens Mountain Fault, VF - Vale Fault, NNR - North Nevada Rift.
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The Skukum Group is a 55-million-year-old volcanic group in northern British Columbia and southern Yukon, Canada. It consists of discrete calderas in a linear range from the south end of Atlin Lake to Bennett Lake, then to Aishihik Lake. The cluster of rocks crowds the Mount Skukum gold deposit southwest of Whitehorse. One of the calderas within the group is the Bennett Lake Volcanic Complex.
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A pluton, Cabeza de Vaca, lies in the southern and eastern sectors of the caldera and has dimensions of . Within the caldera several smaller calderas formed, from north to south Caldera Cerro Puquios, Caldera Bellavista, Caldera Agua Nueva, Caldera El Durazno and Caldera Lomas Bayas. The Puquios caldera partly overlaps the Carrizalillo caldera margin. These subsidiary calderas have left lava conduits, lacustrine and intrusive structures and other geomorphologic features.
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He later signed scenography for a number of productions. He did many installations of land art, especially on volcanoes – even in some cases inside the calderas of active volcanoes.
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Such a feature may have resulted from collapse of a magma chamber underlying the central part of the crater. The collapse feature is an analog of Earth's volcanic calderas.
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View from Abra del Acay over the caldera towards Nevado del Acay Negra Muerta is a caldera in Argentina. It is part of the volcanic centres of the Andean Volcanic Belt, which has formed a number of calderas in large ignimbrite producing eruptions. These calderas include Aguas Calientes, Cerro Panizos, Galan, Negra Muerta and La Pacana. Some of these volcanic centres appear to be associated with large fault zones that cross the Puna.
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Kone, also called Gariboldi, is made up of seven nested calderas, lava flows and basaltic cinder cones. (Not to be confused with the Garibaldi Volcanic Belt in Northern America.) There are two fault lines that have caused the volcanic activity within Kone, normal faults, which are part of the Wonji fault belt and ring fractures. The normal faults cause magma to rise inducing the volcanic activity. The ring fractures have caused the calderas collapse.
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Although the McDermitt volcanic field on the Nevada–Oregon border is frequently shown as the site of the initial impingement of the Yellowstone Hotspot, new geochronology and mapping demonstrates that the area affected by this mid-Miocene volcanism is significantly larger than previously appreciated. Three silicic calderas have been newly identified in northwest Nevada, west of the McDermitt volcanic field as well as the Virgin Valley Caldera. These calderas, along with the Virgin Valley Caldera and McDermitt Caldera, are interpreted to have formed during a short interval 16.5–15.5 million years ago, in the waning stage of the Steens flood basalt volcanism. The northwest Nevada calderas have diameters ranging from 15–26 km and deposited high temperature rhyolite ignimbrites over approximately 5000 km2.
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Several other prominent gravity and magnetic highs are arranged along the Mugrave Block strike line, one of which was drilled by BHP in the 1990s through 300m of Permian glacial sediments. This caldera is composed of highly tectonised, stretched felsic volcanic rocks, interleaved with a significant thickness of equally sheared titaniferous differentiated mafic sills. The best interpretation of this, and probably also of the Palgrave Caldera is that they represent hot spots along the Musgrave Block where significant magma flux penetrated, formed volcanic calderas with large subvolcanic granite intrusions, and associated mafic volcanism. The relationship of the large granite calderas to the 1050-1080 Ma volcanics has been postulated as one in which the granite calderas were the source for the intermediate and felsic volcanic rocks.
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The Central Andes are the site of extensive ignimbrites that were erupted from large calderas usually located within the adjacent Altiplano, east of the principal volcanic arc. Many of these calderas are part of the Altiplano-Puna volcanic complex, a large volcanic complex covering a surface area of with about of ignimbrites. La Pacana is the largest caldera of the Altiplano-Puna volcanic complex. The ignimbrites form a surface that lies at an average elevation of .
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Although the particular Volcanic Explosivity Index (VEI) of the Silverthrone Caldera is unknown, the chemistry and structure of the volcano can be compared to other calderas that have a history of producing some of the world's most violent eruptions. It is about long and wide while the Crater Lake caldera in Oregon, United States is long and wide. Such calderas are usually formed by large cataclysmic eruptions reaching 7 on the Volcanic Explosivity Index (described as "super-colossal").
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The larger caldera has dimensions of with a rim altitude of . Extended volcanic activity has generated two nested calderas, a number of lava domes and lava flows and a central resurgent dome.
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Such a feature may have resulted from collapse of a magma chamber underlying the central part of the crater. The collapse feature is an analog of Earth's volcanic calderas. See unnamed crater 1.
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A comagmatic province is a geologic area of the same type and age igneous rock deriving from the same crustal magma. The Roman region is post-collisional; that is, the intrusions were not a result of the lateral stresses that created Italy and raised the Apennines, but were subsequent to Italy's creation. The Volsinian is the northernmost region. At relatively low altitude, the Vulsini calderas cover about and contain four Pleistocene-age depressions known as Bolsena, Latera, Vepe and Montefascione calderas.
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Research studies have concerned the fundamental processes of magmatism, hydrothermal systems, and ore deposition. Nearly 40 deep cores have been examined, resulting in extensive subsurface data. Valles Caldera is the younger of two calderas known at this location, having collapsed over and buried the older Toledo Caldera, which in turn may have collapsed over yet older calderas. The associated Cerros del Rio volcanic field, which forms the eastern Pajarito Plateau and the Caja del Rio, is older than the Toledo Caldera.
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It has a 350 by 150 km north–south elongated central depression containing the calderas Nili Patera and Meroe Patera, which are about 2 km deep. The floors of the calderas are unique among large Martian volcanoes as they are not elevated relative to the terrain surrounding Syrtis Major. This may account for the high degree of magmatic evolution and hydrothermal activity seen in Nili Patera. The floor of Nili Patera is the less cratered, and therefore the younger, of the two.
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Christopher Newhall and Daniel Dzurisin, 1988, Historical Unrest at Large Calderas of the World, U.S. Geological Survey Bulletin 1855 Although much smaller than the Island Park Caldera, the Henry's Fork Caldera is still sizeable at long and wide and its curved rim is plainly visible from many locations in the Island Park area. Of the many calderas formed by the Yellowstone hotspot, including the later Yellowstone Caldera, the Henry's Fork Caldera is the only one that is currently clearly visible.this qualitative statement is easily verified by reviewing the Yellowstone area in Google Earth It is one of a succession of supervolcanoes and calderas that formed the Snake River Plain. The Henrys Fork of the Snake River flows through the Henry's Fork Caldera and drops out at Upper and Lower Mesa Falls.
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Mount Jarvis is a shield volcano. high, with one or more indistinct summit calderas. It is covered with ice and erupted between 1.7 million and 1 million years ago.Richter et al, pp. 23–25.
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Such features may include volcanic crater lakes and lava domes after the event. However, calderas can also form by non-explosive means such as gradual magma subsidence. This is typical of many shield volcanoes.
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Charles R. Bacon is an American expert in geology at the United States Geological Survey in the Volcano Hazards Team who has done a tremendous amount of work on Crater Lake National Park's geology. He earned his BS in Geology at Stanford in 1970 and his Ph.D. in Geology from University of California, Berkeley in 1975. His current research interests include physical volcanology, petrology, geochemistry, and eruptive histories of calderas, emphasizing detailed study of Crater Lake, Oregon, and Veniaminof and Aniakchak calderas, Alaska Peninsula.
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Glacial erosion has affected the older volcanic centres. Ignimbrites fill these calderas. Within this caldera lies a stratovolcano with a smaller wide caldera; Nemo Peak proper is located within this smaller caldera. This forms a somma volcano.
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This series of volcanoes is part of the Central Volcanic Zone, one of several volcanic belts in the Andes, and there are no recorded historical eruptions at the Tatio volcanoes. El Tatio is also part of the Altiplano–Puna volcanic complex (APVC), a system of large calderas and associated ignimbrites, which have been the sources of supereruptions. Some of these calderas may be the source of heat for the El Tatio geothermal system. El Tatio is a geothermal field with many geysers, hot springs, and associated sinter deposits.
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Throughout the caldera, the grass valleys appear groomed: there are few saplings and mature trees lack lower branches. This is due to heavy browsing by elk and cattle and because of frequent grass fires of human and natural origin which kill the lower branches on the Engelmann spruce, Douglas-fir and Ponderosa pine that populate the uplands around the grasslands dominating the bottoms of the calderas. Extreme cold in winter prevents tree growth in the bottoms of the calderas. The grasslands were native perennial bunch grass maintained by frequent fire before sheep and cattle grazing.
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Supervolcanoes, BBC2, 3 February 2000 There is no direct evidence, however, that either theory is correct, and there is no evidence for any other animal decline or extinction, even in environmentally sensitive species. There is evidence that human habitation continued in India after the eruption. Eruptions forming even larger calderas are known, especially La Garita Caldera in the San Juan Mountains of Colorado, where the Fish Canyon Tuff was blasted out in eruptions about 27.8 million years ago. At some points in geological time, rhyolitic calderas have appeared in distinct clusters.
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Mount Moulton is formed by a complex of glaciated but largely uneroded shield volcanoes with ice-filled calderas, each of which is about wide. The calderas are apart. Additionally the Prahl Crags – remnants of the former caldera rim – are found south, Gawne Nunatak west, Edwards Spur northeast and the Moulton Icefalls on the northern side of the mountain. The total volume of the complex is about , comparable to that of Mount Shasta in the Cascade Range, and is one of the largest volcanoes in the Flood Range and Ames Range.
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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. The volcano's summit consists of two nested calderas, with an andesitic lava dome.
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Piz Calderas is a mountain of the Albula Alps, overlooking Mulegns in the canton of Graubünden. It is the highest summit of the group located between the Julier and Albula Pass. On its east side lies the Val Bever.
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The mayor of the Bolívar Municipality is Iván Dario Maldonado, elected on October 31, 2004 with 49% of the vote. He replaced Alberto Melean shortly after the elections. The municipality is divided into three parishes; Barinitas, Altamira, and Calderas.
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R (2002) Elliptic calderas in the Ethiopian Rift: control of pre-existing structures. Journal of Volcanology and Geothermal Research. 119:189–203 Three Silicic phases and then a basalt phase. The most recent basalt phase is dated around 1820.
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The Yellowstone hotspot is most notable for the Yellowstone Caldera and the many calderas that lie in the Snake River Plain while the Anahim hotspot is most notable for the Anahim Volcanic Belt, currently found in the Nazko Cone area.
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Piz Picuogl is a mountain of the Albula Alps, located between Mulegns and the Val Bever, in Graubünden. On its northern side lies the glacier Vadret da Calderas. On the same ridge is located the lower summit Tschima da Flix.
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Volcanism of Western Canada has produced lava flows, lava plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, greenstone belts, submarine volcanoes, calderas, diatremes and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds.
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The Faial-Pico Channel () is an long channel that separates the islands of Faial and Pico in the central group of the archipelago of the Azores. The strait is divided into various depressions, calderas and micro-systems, referred to as Baixas.
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The Bennett Lake Volcanic Complex was formed when the ancient Kula Plate was subducting under North America during the early Eocene period.Crustal recycling during subduction at the Eocene Cordilleran margin of North America Retrieved on 2007-06-26 Cataclysmic eruptions from the Bennett Lake Volcanic Complex were from vents along arcuate fracture systems that ejected out about of glowing avalanches of pyroclastic rock called pyroclastic flows. Evacuation of the underlying magma chamber was followed by several stages of collapse to form two calderas, one nested inside the other, that produced an elliptical depression by across. The calderas were from to deep.
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After Newberry Volcano, Mazama is the second largest Quaternary volcanic edifice in Oregon, and the most voluminous, with an overall volume of . Mazama is the newest of the Quaternary calderas in the Cascade Volcanic Arc, which also include the Newberry calderas and the caldera at the Medicine Lake Volcano. Quaternary monogenetic volcanism throughout Oregon's High Cascades includes cinder cones, lava fields, and small shield volcanoes, which have produced lava ranging from low-potassium, high-alumina olivine tholeiite to medium-potassium calc-alkaline basalt, basaltic andesite to shoshonitic basaltic andesite. The Mazama volcanic complex originally formed as a cluster of overlapping edifices.
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The Henry's Fork Caldera is nested inside of the Island Park Caldera and the calderas share a rim on the western side. The earlier Island Park Caldera is much larger and more oval and extends well into Yellowstone Park. Although much smaller than the Island Park Caldera, the Henry's Fork Caldera is still sizeable at long and wide and its curved rim is plainly visible from many locations in the Island Park area. Of the many calderas formed by the Yellowstone Hotspot, including the later Yellowstone Caldera, the Henry's Fork Caldera is the only one that is currently clearly visible.
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The La Garita Caldera is one of a number of calderas that formed during a massive ignimbrite flare-up in Colorado, Utah and Nevada from 40–18 million years ago, and was the site of massive eruptions about , during the Oligocene Epoch.
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Such a feature may have resulted from collapse of a magma chamber underlying the central peak ring complex of the crater. The collapse feature is an analog of Earth's volcanic calderas. Scarlatti is thought to have the same age as the Caloris basin.
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The western mountain is composed of four overlapping and eroded stratovolcanoes, with a cinder cone field at the western end. It has not been historically active. The eastern mountain is a large shield volcano with two overlapping summit calderas, which last erupted in 1937.
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The terrestrial volcano Emi Koussi (in Chad) has been studied as an analog of Elysium Mons. The two shield volcanoes have summit calderas of similar size, but Elysium Mons is 3.5 times larger in diameter and 6 times higher than its counterpart on Earth.
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The Cochetopa caldera, with Cochetopa Dome within it, is one of the most recognizable of the calderas in the region. Helping preserve the structure of this particular caldera is that its development was more recent than many of the larger calderas elsewhere in the San Juan Mountains, thus there was less regional volcanism to disrupt the caldera's structure. Also, the caldera was only modestly filled with post-subsidence sediments and much of this was weaker, tuffaceaus deposits, which have been more readily eroded from the caldera floor. And lastly, the caldera is drained through Cochetopa Canyon where hard, Precambrian igneous rock has limited down cutting and erosion of the caldera.
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It is and oblong in shape. Most supervolcano calderas of explosive origin are slightly ovoid or oblong in shape. Because of the vast scale and erosion, it took scientists over 30 years to fully determine the size of the caldera. La Garita is considered an extinct volcano.
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To the northwest of Ritter is a system of parallel rilles designated Rimae Ritter. These follow a course to the northwest. Ranger 8 flew over Ritter prior to impact in Mare Tranquilitatis. Both Sabine and Ritter were originally believed to be calderas rather than impact craters.
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Zavaritski Caldera (, Vulkan Zavaritskogo) is a caldera located in the central part of Simushir Island, Kuril Islands, Russia. Lake Biryuzovoe partially fills the youngest of three nested calderas on the volcano. The volcano is named after Alexander Nikolayevich Zavaritski, scientist of the Academy of Sciences of the Soviet Union.
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Two lakes, Balshoe and Kraternoe, are located within calderas at the summit of Ksudach. These lakes, along with hot springs and the surrounding wilderness, make the Ksudach Volcano region a popular trekking destination. In the event of renewed volcanic activity, its remote location minimizes its potential hazard to humans.
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Also found nearby are Neogene-age calderas. Sixteen volcanoes in Peru are active or potentially active. There is no habitation on Coropuna above , but numerous villages dot the lower slopes. Agriculture and animal husbandry are the most common economic activities; there are copper and gold mines as well.
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Semeru rises steeply above the coastal plains of eastern Java. Maars containing crater lakes have formed along a line through the summit of the volcano. It was formed south of the overlapping Ajek-ajek and Jambagan calderas. Semeru lies at the south end of the Tengger Volcanic Complex.
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Later, calderas formed. Eventually, late in the history of the volcanoes parasitic vents were active. The volcanoes are all surmounted by rocks composed of trachyte, phonolite, pantellerite, or comendite. Their activity has been attributed either to the reactivation of crustal structures or to the presence of a mantle plume.
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As Pangaea broke apart and land masses were shifting, large features like the White Mountains were formed; at the same time, as this multitude of cracks was occurring, magma rose up and filled many of these voids. In this manner calderas were formed throughout the White Mountains as magma receded; these calderas then subsequently erupted on a scale dwarfing the 1980 eruption of Mount St. Helens. The results of these massive eruptions can be found in such places as the Ossipee Mountains, which are located proximal to the White Mountains. The Ossipee Mountains contain substantial amounts of volcanic rock, and the many ring dikes across the region indicate that there was once an active volcano on the site.
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The Galápagos's shape is due to the pattern of radial and circumferential fissure, radial on the flanks, but circumferential near the caldera summits. It is the circumferential fissures which give rise to stacks of short lava flows. The volcanoes at the west end of the archipelago are in general, taller, younger, have well developed calderas, and are mostly composed of tholeiitic basalt, while those on the east are shorter, older, lack calderas, and have a more diverse composition. The ages of the islands, from west to east are 0.05 Ma for Fernandina, 0.65 Ma for Isabela, 1.10 Ma for Santiago, 1.7 Ma for Santa Cruz, 2.90 Ma for Santa Fe, and 3.2 Ma for San Cristobal.
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Ngatemato seamounts (Name derived from a ruling family in Rapa) are a series of seamounts in the southern Pacific Ocean. These seamounts have the shape of ridges and display calderas. The Aureka () and Make () seamounts are part of the Ngatemato track. Dredged rocks are weakly tholeiitic basalts of Oligocene age.
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Azrou volcanic field is a volcanic field in Morocco, close to Ifrane in the Middle Atlas. Calderas and volcanic cones characterize the field in the Azrou area and are of Pliocene to Pleistocene age. Volcanic activity occurred until 600,000 years ago and a number of fresh volcanic features are present.
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Nemo Peak () is a stratovolcano located at the northern end of Onekotan Island, Kuril Islands, Russia. It is truncated by two nested calderas, with the cone of Nemo Peak itself rising in the southwest end of the youngest caldera and a crater lake partially filling the northeast part, named Ozero Chernoye.
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The island is a double caldera with a scoria hill rising in the middle. It is the peak of two overlapping stratovolcanoes and their associated calderas, Mount Higashi and Mount Nishi. The highest peak, at , is part of a triple volcano. The peak rises close to from the sea floor.
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"Review of 15 years experience of the Ogachi Hot Dry Rock Project with emphasis on geological features," in Proceedings, 24th New Zealand geothermal workshop (November 13–15, 2002: University of Auckland, Auckland, New Zealand), pp. 55–60 calderas in Japan; and in the Cooper Basin, Australia.Chopra, P., and Wyborn, D., 2003.
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Different observations have yielded different sizes and numbers of supposed craters; González-Ferrán et al. 1995 reported several craters and calderas with sizes ranging , while Kobayashi et al. 2010 observed fewer craters and none of them larger than . These craters were later interpreted as being actually glacial cirques containing tarn lakes.
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Salar Grande is a caldera in Chile. The region originally contained various rocks with ages ranging from Neoproterozoic to Triassic. Starting with the Oligocene, the Central Volcanic Zone was active and gave rise to calderas, lava domes, pyroclastic cones and stratovolcanoes. The region lies at an elevation of and largely unknown to people.
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An interpretation of its name is that it's a combination of the Quichua words Cari (man), huay (wind) and razu (Ice/Snow) (Schmudlach 2001). Local Indian mythology narrates that Carihuairazo and El Altar which are both volcanic calderas have been destroyed by Taita (Father) Chimborazo fighting for the grace of Mamá Tungurahua.
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Piz Jenatsch is a mountain of the Albula Alps, located in the canton of Graubünden. It has an elevation of 3,251 metres above sea level and it is located east of Piz d'Err and Piz Calderas, between the valleys of Val d'Err and Val Bever. The closest locality is Tinizong on the west side.
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For that reason, very large magmatic flows are regarded as unlikely in the present day. The majority of the Wrangell volcanoes are shield volcanoes with large collapse calderas at their summits. All but Mount Wrangell have been modified by glaciers to sharper, steeper relief than the gentle, rounded forms that characterize young shield volcanoes.
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Laguna de Calderas is a crater lake in the municipality of Amatitlán, Guatemala, Guatemala. It is located approximately 6 km south of Lake Amatitlán and 3 km north of the currently active vent of the Pacaya volcano. The lake has a surface area of 11 ha and is situated at an altitude of 1778 m.
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Because of the western climatic influences, the amount of rainfall in the Țarcu Mountains is quite large. Snow may fall at altitudes above 1500 metres at any time in the year, while the snow pack usually lasts from October or November until June or even July in the glacial calderas of the highest peaks.
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Until about below sea level, the area is dominated by extensive uninterrupted boulders, with a terrain that is rugged and divided by metres. Some of these cassums are broken by abrasive calderas, formed from large boulders grinding into the reef floor. These covas de gigante (giants' holes), some deep and diameters that permit movement.
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The best estimate is considered to be . Palomo rises from an elevation of about , and it covers a surface area of . Beneath the volcano lie two calderas with diameters of and ; the summit has a double crater as well, which may reflect a northeastward migration of volcanic activity. northeast of Palomo lies the high Andrès subsidiary vent.
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The basement in the area is formed by Miocene-Pliocene sedimentary rocks and volcanic rocks. During the Pleistocene calderas, lava plateaus, somma volcanoes like pre-Ilinsky stratovolcanoes formed in the area. One caldera that formed in the area is the Pauzhetka Caldera, of middle Pleistocene age. the possibility that a later caldera existed in the Pauzhetka caldera was considered.
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With its width of nearly , the crater of Nemrut Volcano is one of the largest calderas of the world. The western half of the crater is covered by the lake. At the summit, there are five lakes, two of them existing permanently and the others seasonal. The biggest of the lakes is Lake Nemrut in the form of crescent.
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The local economy is based on agriculture and farming, the residents keep sheep and llama and grow vegetables. Tourism plays an important part in the local economy as many tourists come to see the nearby mountains volcanoes and calderas including Galán caldera and the Antofagasta de la Sierra volcanic field. The village holds an annual Festival of the dead.
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Akademia Nauk ( - Academy of Sciences) is a volcano located in the southern part of Kamchatka Peninsula, Russia. The volcano is filled with a few calderas, and the most notable one is known as Karymsky Lake ( named after Karyms). The volcano is named after the Росси́йская Акаде́мия Нау́к, the Russian (Soviet) Academy of Sciences. It last erupted in January 1996.
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Potrerillos is a caldera in Chile, in the Atacama Region. Potrerillos has a diameter of and is filled by ash flows and andesitic, basaltic and rhyolitic lava flows. The caldera was active 65-56 million years ago. It and the neighbouring Cerro Vicuña and El Salvador calderas form the Indio Muerto volcanic complex, which was influenced by local faults.
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Less common volcanic landforms include cinder cones, volcanic plugs, lava domes and calderas. These diverse formations were created by different styles of volcanic activity, including Peléan and Plinian eruptions. Eruptions along the length of the chain have created at least three major volcanic zones. The first began in the Powder Mountain Icefield 4.0 million years ago.
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The average caldera diameter on Venus is . The average caldera diameter on Io is close to , and the mode is ; Tvashtar Paterae is likely the largest caldera with a diameter of . The average caldera diameter on Mars is , smaller than Venus. Calderas on Earth are the smallest of all planetary bodies and vary from as a maximum.
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Because there is no plate tectonics on Venus, heat is mainly lost by conduction through the lithosphere. This causes enormous lava flows, accounting for 80% of Venus' surface area. Many of the mountains are large shield volcanoes that range in size from in diameter and high. More than 80 of these large shield volcanoes have summit calderas averaging across.
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The extensive icefields around Mount Silverthrone are receding and are small compared to their former extent, but they are an impressive indication of how much of British Columbia looked 10,000 years or more ago. Silverthrone contains one of the few calderas buried beneath the ice caps of western Canada, another example being Mount Edziza in far northwestern British Columbia.
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The floor of Era Kohor is thus deep white. Three maars and several scoria cones are also nested within the combined caldera, along with lava domes and lava flows. Debris from explosive eruptions fills the calderas. The Kohor pumices and two sets of ignimbrites cover the flanks of Emi Koussi, which steepen as they approach the summit.
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LeMasurier and Thompson, 1990, p.194 The northwesterly summit is associated with its own caldera, which is partly cut by the Mount Hampton caldera on the southeastern flank and buried by the lava flows from the latter.LeMasurier and Thompson, 1990, p.189 The centres of the two calderas are about apart.Rocchi, LeMasurier and Vincenzo 2006, p.
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About 20 major calderas are found in the CVZ, especially in the region between 21 and 25° southern latitude where the Altiplano-Puna volcanic complex can be found. These ignimbrites, lava flows and subvolcanic bodies. Smaller ignimbrites are found in the southern part of the CVZ. The Pucarilla-Cerro Tipillas volcanic complex is formed by pyroclastic flows.
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"Los Castillos" mill is located near the "La Bellaca" farmhouse, close to the town of Calderas; the artisan process of making panela is carried out at the mill, which was produced by the locals since past times. In Calderas, there are natural places with recreational facilities, such as the "La Piedra del Patio" spa, on the banks of the Azul River. The house of Avelino Moreno culture and the "Centro de Enseñanza para el Desarrollo Rural" (CENDER) is located here. Near the city of Barinas, there are two important reservoirs: the Manuel Palacio Fajardo (Masparro), located 15 minutes from the town of Barrancas, and Juan Antonio Rodriguez Dominguez (Boconó - Tucupido), located on the border with the Portuguese State; tourists can go on boat trips, kayaking, jet skiing, bird watching, and controlled sport fishing.
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The caldera is also a coalescence of at least two large mafic shield volcanoes that formed more than 2703 million years ago.Blake River Group evolution: characteristics of the subaqueous Misema and New Senator calderas The rim of the Misema Caldera contains a 10-15 kilometre wide inner and outer ring zone, in which many mafic ring dike complexes and subaqueous pyroclastic sediments are detected. The mafic ring dike structures may be deeper level expressions of summit calderas related to a shield volcano phase while the pyroclastic fragments could either be associated with satellite cones or the result of Misema caldera collapse. The Misema Caldera is the oldest and largest caldera associated with the Blake River Megacaldera Complex and is comparable in size to the Lake Toba caldera in Indonesia.
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The San Juan volcanic field is part of the San Juan Mountains in southwestern Colorado. It consists mainly of volcanic rocks that form the largest remnant of a major composite volcanic field that covered most of the southern Rocky Mountains in the Middle Tertiary geologic time.Steven, Thomas A.; Lipman, Peter W. (1976). "Calderas of the San Juan Volcanic Field, Southwestern Colorado".
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The highlands are located in a spreading zone at the intersection of branches of two tectonic plates, the African Plate and Somali Plate, resulting in distinctive and prominent landforms. The highlands are named for the many craters and calderas present. As is common in spreading zones, volcanoes can be found here. Magma, rising to fill the gaps, reaches the surface and builds cones.
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Melts caused by subduction have generated the volcanoes of the Andean Volcanic Belt including the APVC. The volcanic province is located between 21° S–24° S latitude. The APVC spans the countries of Argentina, Bolivia and Chile. In the Miocene–Pliocene (10-1 mya), calderas erupted felsic ignimbrites in four distinct pulses separated by periods of low levels of activity.
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Osorno volcano in Chile is an example of a well- developed stratocone. Stratocones are large cone-shaped volcanoes made up of lava flows, explosively erupted pyroclastic rocks, and igneous intrusives that are typically centered around a cylindrical vent. Unlike shield volcanoes, they are characterized by a steep profile and periodic, often alternating, explosive eruptions and effusive eruptions. Some have collapsed craters called calderas.
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San Jerónimo is part of a long alignment of volcanoes along the Calama-Olacapato-El Toro fault. This string of volcanoes is diverse, including calderas and stratovolcanoes on the one hand and plutons and monogenetic volcanoes on the other hand. One volcano that is part of this structure is Aguas Calientes caldera, on whose border the San Jerónimo volcano is constructed.
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Lava flows extend down from the summit area of Nemo Peak and are covered with scoria. The complex is surrounded by older rocks, some of Tertiary age. To the south the complex borders the old Tao-Rusyr and Shestakov volcanic rocks. Another volcano named Asyrmintar is found on the northeastern margin of the two older calderas; Asyrmintar is an eroded remnant.
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The Prizrak caldera has a diameter of about 4 km. It is located on top of the site of an ancient stratovolcano whose base has a diameter of about 10 km. The slopes of the caldera feature a network of erosional valleys. Within the Prizrak caldera complex are at least three partially nested calderas, each about 3 to 5 km in diameter.
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Based on neodymium isotope ratios, some of the basement rocks are about one billion years old. The volcano is part of a group with other volcanoes of the Lipez region. In this region, arc and back-arc volcanism occur in the same area and have generated some of the largest calderas in the world. These include Cerro Guacha, Pastos Grandes and Vilama.
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After the ignimbrite cooled and solidified, cracks formed in the rocks and were later eroded by wind. The Robledo and Pie de San Buenaventura calderas were formed during the early activity. The volcano appears to have erupted repeatedly during the Holocene. Explosive eruptions took place between 8,830 ± 60 and 5,480 ± 40 years before present and deposited tephra and ignimbrites south of Cerro Blanco.
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Volcanic islands are common in the Izu segment, including O-shima, Hachijojima, and Miyakejima. The Izu segment farther south also contains several submarine felsic calderas. The Izu arc segment is also punctuated by inter-arc rifts. The Bonin segment to the south of the Sofugan Tectonic Line contains mostly submarine volcanoes and also some that rise slightly above sealevel, such as Nishino-shima.
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The Mount Pleasant Caldera is a large eroded Late Devonian volcanic caldera complex, located in the northern Appalachian Mountains of southwestern New Brunswick, Canada. It is one of few noticeable pre-Cenozoic calderas, and its formation is associated to a period of crustal thinning that followed the Acadian orogeny in the northern Appalachian Mountains. It sits relatively near to the coastline.
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Menengai Crater is a massive shield volcano with one of the biggest calderas in the world, in the Great Rift Valley, Kenya. It is the largest volcano caldera in Kenya and the second largest volcano caldera in Africa. Volcanic formed rich loam soils enrich the adjacent farmland arounds its flanks. The crater is on the floor of the Rift Valley.
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Syrtis Major Planum is a vast Hesperian-aged shield volcano located within the albedo feature bearing the same name. The volcano is 1200 km in diameter but only 2 km high. It has two calderas, Meroe Patera and Nili Patera. Studies involving the regional gravity field suggest a solidified magma chamber at least 5 km thick lies under the surface.
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Sollipulli Caldera, located in central Chile near the border with Argentina, filled with ice. The volcano is in the southern Andes Mountains within Chile's Parque Nacional Villarica. Some volcanoes, such as the large shield volcanoes Kīlauea and Mauna Loa on the island of Hawaii, form calderas in a different fashion. The magma feeding these volcanoes is basalt, which is silica poor.
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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.
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Since "supervolcano" calderas can have eruptive lifespans sometimes measured in millions of years, a caldera that has not produced an eruption in tens of thousands of years is likely to be considered dormant instead of extinct. Some volcanologists refer to extinct volcanoes as inactive, though the term is now more commonly used for dormant volcanoes once thought to be extinct.
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The collapsed calderas of Cirque de Cilaos, Cirque de Mafate, and Cirque de Salazie also draw tourists. The Le Maïdo viewpoint is located at an altitude of 2,205 m (7,232 ft) and has excellent views of the coast. There is good surfing off the island's west coast. Réunion's capital Saint-Denis and the lagoons of St-Gilles-les Bains also attract tourists.
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This field covers a surface area of . The presence of two calderas has been inferred, one at Tankha Tankha in the northern part of the field and one at Condoriri in the southern part of the field. The Tankha Tankha caldera has a resurgent dome which has erupted domes and lava flows. Other volcanic landforms in the field are lava domes.
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Both of these faults have caused activity within Kone's recent history. The calderas widths can range from 1.5 to 5 km. There are many rock types identified at Kone and they are divided into five main groups, trachytes, comenditic rhyolites, ignimbrites, pumices, syenite inclusions and basalts. Trachytes and comenditic rhyolites form the main volume of the rock in the Complex.
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Satellite image of Kone volcanic complex Kone's name is a recent addition taken from a local tribal word. The historical name of Kone was Gariboldi. Named according to local legend after an engineer who was responsible for building a road through two of the collapsed calderas. Thereby connecting Addis Ababa to Djibouti during the Italian occupation of Ethiopia during the 1940s.
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Layers of lava and pyroclastics are discernible in the craters. These craters are not collapsed calderas, and there is no evidence of the deposits a large explosion would produce. Remnants of a previous edifice are visible in the craters; this older edifice constitutes the bulk of the eastern cone. There are traces of a collapse of the volcano towards the northeast, with an associated horseshoe-shaped scar.
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The San Juan volcanic field has been a historically important mining district, producing lead, zinc, copper, gold, and silver. The ores were mostly deposited in and near calderas that experienced significant postcaldera activity. Ore veins were concentrated in fractures associated with caldera activity and in postcaldera intrusive bodies. The greatest mineralization took place near the youngest and most silicic intrusions of each caldera cycle.
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Other active centres include the El Tatio and Sol de Mañana geothermal fields and the fields within Cerro Guacha and Pastos Grandes calderas. The latter also contains <10 ka rhyolitic flows and domes. The implications of recent lava domes for future activity in the APVC are controversial, but the presence of mafic components in recently erupted volcanic rocks may indicate that the magma system is being recharged.
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The island consists of several overlapping stratovolcanoes, and it contains two calderas each with central volcanic cones. About 10 historical eruptions have been recorded since the late 18th century, the most recent in 1993. All recent activity has occurred at Pyre Peak, the cone within the western caldera and the highest point on the island, and has produced explosive eruptions and basaltic lava flows.
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Melimoyu is a stratovolcano (Mapudungun meli="four"; the name means "four breasts".) in Chile. It is an elongated volcanic complex that contains two nested calderas of and width. An ice cap has developed on the volcano with a couple of outlet glaciers. Melimoyu has not erupted in recent times, but during the Holocene two large eruptions took place and ejected ash at large distances from the volcano.
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Putana is part of the Central Volcanic Zone, which aside from this volcano contains a number of large calderas associated with silicic volcanism. Over 13 volcanoes in the Central Volcanic Zone have been active in historical time, out of about 69 with evidence of Holocene activity. Of these volcanoes Láscar is the most active volcano in the Central Volcanic Zone; a major eruption occurred there in 1993.
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The volcano's structure has changed significantly over time, from a parasitic cone to its current makeup of alumina basaltic lava flows and pyroclastic debris. A cone made of tuff tops the mountain, built over the ancient calderas of the volcano. Dating suggests that the last eruptions on the island, from East Cape, were at least 2000 years ago, and could have possibly taken place before the Holocene.
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Tacaná is a stratovolcano (composite volcano) that is surrounded by deeply dissected plutonic and metamorphic terrain. It has a wide caldera, with its elongated summit dominated by several lava domes and three large calderas breached to the South. Mild phreatic eruptions of Tacaná took place in historical times. Its most powerful known explosive activity, which included pyroclastic flows, occurred at about 70 AD (± 100 years).
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The volcanic field has formed on top of older, Oligocene to Miocene age volcanic rocks and calderas, but its own activity commenced only about 6 million years ago. The reasons for the volcanic activity there are not well known. The volcanic field has produced various types of basaltic magma and also trachyte; the most recent eruption was about 38,000 years ago and renewed activity is possible.
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Relief map Mount Natib is a stratovolcano type of volcano topped by a acorn-shaped Natib Caldera that is open to the northwest. East of its caldera is the smaller wide Pasukulan Caldera. The highest peak of Mount Natib has an elevation of asl and is at the point of convergence of the two calderas. The caldera complex has an overall base diameter of .
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The Caldera Agua Nueva lies northeast of Durazno and is filled with a thick post-Carrizalillo ignimbrites. The Bellavista caldera is similar to the other calderas and also forms an arc with a diameter of . Trachyandesitic banks lie on its western margin, and in the caldera lies a deposit of welded pumice thick. It contains lithic fragments including monzonite, likely formed from blocks sagging into the caldera.
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Cinder cones dot the landscape of the Snake River Plain. Some are aligned along vents, the fissures that fed flows and cone-building eruptions. Calderas, great pits formed by explosive volcanism, and low shield volcanoes, and rhyolite hills are also part of the landscape here, but many are obscured by later lava flows. Geologists usually associate volcanic eruptions with the boundaries between colliding or diverging plates.
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The volcano formed about 200,000 years ago and the prominent 12 x 8 km caldera formed about 8000 years ago. The caldera floor is covered with numerous post caldera lava flows. The Menengai volcano is considered one of the best-preserved Krakatau-style calderas in the world. Menengai has very little sediment in the caldera which is a thick mass of lava boulders and inaccessible ridges.
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Kari-Kari is a Miocene caldera in the Potosi department, Bolivia. It is part of the El Fraile ignimbrite field of the Central Volcanic Zone of the Andes. Volcanic activity in the Central Volcanic Zone has generated 44 volcanic centres with postglacial activity and a number of calderas, including the Altiplano-Puna volcanic complex. Kari-Kari is a caldera whose dimensions are variously considered to be or .
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A solfatara area in Mt. Mandalagan. Elevation is 1885 metres (6,184 feet), with a base diameter of 26 kilometres. Mandalagan is a deeply dissected complex volcano, with a highly altered volcanic dome. Volcanic activity is reported to include seven volcanic centres, at least five craters and/or calderas up to 2 km in diameter, and a vigorous solfataric area at the highly altered volcanic dome structure.
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The caldera and surrounding area continue to be shaped by ongoing volcanic activity. Seismic investigations show that a low-velocity zone lies beneath the caldera, suggesting the presence of partial melt within a remaining magma chamber at between 5 and 15 km depth. An active geothermal system with hot springs and fumaroles exists today. These calderas and associated volcanic structures lie within the Jemez Volcanic Field.
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Both have shallow-sloping flanks and summit calderas. The main difference between Martian shield volcanoes and those on Earth is in size: Martian shield volcanoes are truly colossal. For example, the tallest volcano on Mars, Olympus Mons, is 550 km across and 21 km high. It is nearly 100 times greater in volume than Mauna Loa in Hawaii, the largest shield volcano on Earth.
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It has also been interpreted as being actually three nested calderas. The Lomas de Montes lie along the northwestern and the Somma de Lars along the southeastern caldera margin. The caldera is filled with sediments as well as a 4.4-4.0 million year old ignimbrite that probably originated in the Laguna Amarga caldera. The depression of the caldera features a crater lake, called Laguna Wheelwright.
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A larger, shallower depression lies immediately northeast of the smaller caldera. The large depression is about 90 km in diameter and structurally more complex than the small caldera.Mouginis-Mark, P.J.; Harris, A.J.L.; Rowland, S.K. (2007). Terrestrial Analogs to the Calderas of the Tharsis Volcanoes on Mars in The Geology of Mars: Evidence from Earth-based Analogs, M. Chapman, Ed.; Cambridge University Press: Cambridge, UK, p. 76.
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The surrounding calderas have ages of about 200, 400, and 800 Myr old, or earlier. A small, partly preserved depression southeast of the main caldera may be as old as 3.8 billion years (Gyr). If the dates are valid, then Ascraeus Mons may have been active through most of Mars' history. An area of peculiar, fan-shaped deposits (FSD) lies on the volcano's western flank.
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Its peak is above the Venusian average surface elevation. The southern continent is called Aphrodite Terra, after the Greek goddess of love, and is the larger of the two highland regions at roughly the size of South America. A network of fractures and faults covers much of this area. The absence of evidence of lava flow accompanying any of the visible calderas remains an enigma.
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Supposedly the entire Tibesti can be seen from the northern summits. It is a shield volcano with a diameter of or and an estimated volume of . The summit of Emi Koussi is formed by two overlapping calderas, which together form a wide elliptical caldera that extends from northwest to southeast. The northern caldera formed first, then the southern caldera which is about deeper below the northern one.
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Lava flows are subordinate. Luingo is the eruptive centre of the Pucarilla-Cerro Tipillas volcanic complex. Unlike other calderas such as Galan, Luingo is not visible from satellite images; its location and existence has been inferred from analysis of the facies and morphology. This caldera is the source of the Alto de Las Lagunas and Pucarilla ignimbrites and is itself filled by the two Luingo ignimbrites.
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Thus defined, the Yellowstone Supervolcano is the volcanic field which produced the latest three supereruptions from the Yellowstone hotspot; it also produced one additional smaller eruption, thereby creating the West Thumb of Yellowstone LakeWest Thumb Lake is not to be confused with West Thumb Geyser Basin. The caldera created West Thumb Lake, and the underlying Yellowstone hotspot keeps West Thumb Geyser Basin active. See Fig. 22 . See also :File:Yellowstone Caldera map2.JPG. 174,000 years ago. The three supereruptions occurred 2.1 million, 1.3 million, and approximately 630,000 years ago, forming the Island Park Caldera, the Henry's Fork Caldera, and Yellowstone calderas, respectively.Newhall, Christopher G.; Dzurisin, Daniel (1988) Historical Unrest at Large Calderas of the World: U.S. Geological Survey Bulletin 1855 The Island Park Caldera supereruption (2.1 million years ago), which produced the Huckleberry Ridge Tuff, was the largest, and produced 2,500 times as much ash as the 1980 Mount St. Helens eruption.
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Hveravellir At Hveravellir Under Langjökull there are two or more volcanic systems. The calderas can easily be seen from the air. The best known of these is Hveravellir with its hot spring and high temperature area to the east of the glacier. During an Ice Age some shield volcanoes of this system covered the plains with lava in the region of today's Kjölur mountain road: the Kjalhraun (hraun means "lava field").
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Aguas Calientes is a major Quaternary caldera in Salta Province, Argentina. It is in the Central Volcanic Zone of the Andes, a zone of volcanism covering southern Peru, Bolivia, northwest Argentina and northern Chile. This zone contains stratovolcanoes and calderas. The activity of the Central Volcanic Zone is linked to the subduction of the Farallon Plate and later its splinter, the Nazca Plate, below the South American Plate.
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Tocomar is a Pleistocene volcano in the Jujuy Province, Argentina. It is part of the Andean Volcanic Belt, more specifically to its sub-belt the Central Volcanic Zone. The Central Volcanic Zone consists of about 44 active volcanoes and large calderas of the Altiplano-Puna volcanic complex. Volcanism there is caused by the subduction of the Nazca Plate beneath the South America Plate in the Peru-Chile Trench.
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Thereafter, during the third phase, the outpouring of lava and ejecta deposits increased from Tarso Yega, Tarso Toon, Tarso Tieroko and Ehi Yéy; the collapse of these structures formed the first calderas. This phase also saw the formation of the Bounaï lava dome and Tarso Voon. To the east, the lava flows formed the large plateaus of Tarso Emi Chi, Tarso Ahon and Tarso Toon. Emi Koussi increased in height.
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The lake sediments on Samosir Island show that it has risen by at least since the cataclysmic eruption. Such uplifts are common in very large calderas, apparently due to the upward pressure of below-ground magma. Toba is probably the largest resurgent caldera on Earth. Large earthquakes have recently occurred in the vicinity of the volcano, notably in 1987 along the southern shore of the lake at a depth of .
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Cinder cones dot the landscape of the Snake River Plain. Some are aligned along vents, the fissures that fed flows and cone-building eruptions. Calderas, great pits formed by explosive volcanism, and low shield volcanoes, and rhyolite hills are also part of the landscape here, but many are obscured by later lava flows. Evidence suggests that some concentrated heat source is melting rock beneath the Columbia Plateau Province.
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First official map of El Salvador 1859 Modern El Salvador map Salvadorans inhabit the lush Central American nation of El Salvador. El Salvador is one of the seven country in the giant isthmus of Central America. The surface of El Salvador features tropical forest, jungles, mountains, volcanoes, plains (savanna), rivers, lagoons, lakes, calderas and the Pacific Ocean. The forests of El Salvador contain a wide diversity of flora and fauna.
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The change in environment also engenders a change in lava type, and the lava from this stage is mostly fragmented into volcanic ash. These explosive eruptions continue intermittently for several hundred thousand years. Calderas continually develop and fill, and rift zones remain prominent. The phase ends when the volcano has sufficient mass and height (about above sea level) that the interaction between sea water and erupting lava fades away.
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The hypothesis thus predicts that time-progressive chains of volcanoes are developed on the surface. Examples are Yellowstone, which lies at the end of a chain of extinct calderas, which become progressively older to the west. Another example is the Hawaiian archipelago, where islands become progressively older and more deeply eroded to the northwest. Geologists have tried to use hotspot volcanic chains to track the movement of the Earth's tectonic plates.
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Uzon () is a 9 by 12 km volcanic caldera located in the eastern part of Kamchatka Peninsula, Russia. Together with the Geyzernaya caldera it hosts the largest geothermal field in the Kamchatka Peninsula. The calderas were formed in the mid-Pleistocene in several large eruptions that deposited 20–25 km3 of ignimbrite over a wide area. Lake Dalny fills a Holocene maar in the northeast of Uzon Caldera.
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Model demonstrating how caldera volcanoes collapse. Most Ionian volcanoes start as steep-sided shield volcanoes. After an eruptive construct-building phase, the central region collapses to form a caldera. Since steep-sided shield volcanoes have not been observed inside collapsed calderas, this indicates a failure to reform steep-sided volcanoes after the collapse, which can be associated with various variables such as change in temperature, eruptive rate, and/or lava composition.
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Based on welding patterns, the eruption commenced in the southern sector later covered by lava domes and migrated northward. Calculations indicate that the main Panizos ignimbrite has minimum volumina of outside of the calderas and dense rock equivalent. This ignimbrite flow was of comparatively low fluidity, likely due to its high crystal content. The amount of vesicles present in the lower cooling unit is inferior to 20% of volume.
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Planchón-Peteroa is a complex volcano extending in a north-south direction along the border between Argentina and Chile. It consists of volcanoes of various ages with several overlapping calderas. Those include Volcán Planchón, Volcán Peteroa and Volcán Azufre. A partial collapse of the complex about 11,500 years ago produced a major debris avalanche, which followed the course of the Teno River until reaching the Chile Central Valley.
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Its largest historical eruption was at Quizapu Crater, located on the north side of Cerro Azul's summit (see below), and its most active volcanoes are Llaima and Villarrica.Stern et al., pp. 154–156. Cerro Azul, just south of Descabezado Grande volcano, is part of the Descabezado Grande–Cerro Azul eruptive system, a volcanic field that comprises its two large namesake volcanic edifices and several smaller vents, including 12 Holocene calderas.
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Lizards of this family are diurnal and mostly inhabit fairly open habitats in a generally well-studied part of the world. Consequently, the majority of the species and subspecies already were scientifically described several decades ago. In 2016, the first new curly- tailed lizard since the early 1980s was described. The species was found in the coastal dunes of Bahía de las Calderas in the southwestern Dominican Republic.
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The Yellowstone hotspot is a volcanic hotspot in the United States responsible for large scale volcanism in Idaho, Montana, Nevada, Oregon, and Wyoming as the North American tectonic plate moved over it. It formed the eastern Snake River Plain through a succession of caldera-forming eruptions. The resulting calderas include the Island Park Caldera, the Henry's Fork Caldera, and the Bruneau-Jarbidge caldera. The hotspot currently lies under the Yellowstone Caldera.
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The relationship between Aira and Kirishima Magmatic systems Aira caldera is one of the most active and hazardous calderas in the world. It is home to the Kirishima volcanoes, a group of active volcanoes at the north end of Aira caldera. One of these volcanoes, Shinmoedake, has produced two strong magneto-phreatic eruptions, separated by almost 300 years. Starting in December 2009, active diving and inflation before the outbreak were noticed.
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The Magdalena Mountains are an east-tilted fault-block range, superimposed on Cenozoic calderas. The complex geologic history of the range has resulted in spectacular scenery, with unusual and eye-catching rock formations. They form part of the western edge of the Rio Grande Rift Valley, fronting the La Jencia Basin. The mountains remain isolated and natural due to the absence of any significant human development within or near the range.
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Topographic map centered on Olympus and Tharsis The three Tharsis Montes are shield volcanoes centered near the equator at longitude 247°E. All are several hundred kilometers in diameter and range in height from 14 to 18 km. Arsia Mons, the southernmost of the group, has a large summit caldera that is across and deep. Pavonis Mons, the middle volcano, has two nested calderas with the smaller one being almost deep.
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Io, unusually, is heated by solid flexing due to the tidal influence of Jupiter and Io's orbital resonance with neighboring large moons Europa and Ganymede, which keep its orbit slightly eccentric. Unlike any of the planets mentioned, Io is continuously volcanically active. For example, the NASA Voyager 1 and Voyager 2 spacecraft detected nine erupting volcanoes while passing Io in 1979. Io has many calderas with diameters tens of kilometers across.
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First official map of El Salvador 1859 Modern El Salvador map Salvadorans inhabit the lush Central American nation of El Salvador. El Salvador is one of the seven country in the giant isthmus of Central America. The surface of El Salvador features tropical forest, jungles, mountains, volcanoes, plains (savanna), rivers, lagoons, lakes, calderas and the Pacific Ocean. The forests of El Salvador contain a wide diversity of flora and fauna.
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This collision formed the Teshio and Yūbari Mountains. The Ōu Mountains form the backbone of the volcanic part of the inner arc that run from Natsudomari Peninsula in Aomori Prefecture south to Mount Nikkō-Shirane in Tochigi and Gunma prefectures. The volcanic front consists of four north to south lines of Quaternary volcanoes and calderas, which extend the length of the range. It also includes the Quaternary volcanoes of southwestern Hokkaido.
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Part of the Afar Triangle, the Nabro Volcano is one of many volcanic caldera complexes in the northeasternmost part of the East African Rift valley region. The twin calderas likely formed during an eruption of about 20 to 100 cubic kilometres consisting of ignimbrite, although the date of their formation is unknown. The subaerial volume of volcanic material within the Nabro Volcanic Range is likely on the order of .
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Their circular to oval shape in plan view is consistent with emplacement within resurgent calderas. The exposed igneous rocks of the St. Francois are surrounded at depth by the slightly younger (~100 my) widely distributed igneous Spavinaw terrane. The Spavinaw rocks are intersected in drill core across southern Missouri, southern Illinois, northern Arkansas, southern Kansas and northeastern Oklahoma. The Spavinaw rocks occur in outcrop only near Spavinaw, Oklahoma.
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Older pyroclastics from the same centre contain phenocrysts of clinopyroxene, olivine, orthopyroxene and plagioclase. Mamuta is a volcano among a group of Miocene age stratovolcanoes on the western slope of the Andes. These are usually only partially eroded, although preferential erosion of the volcanos' central parts can cause the appearance of erosion calderas. Three ages have been obtained on Mamuta, 8.8±0.5, 9.1±0.6 and 14.5 million years ago.
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Cerro Bitiche is a volcanic field in Argentina. It is located east of the Central Volcanic Zone away from the volcanic arc within the Altiplano-Puna volcanic complex (APVC), close to Zapaleri volcano. The field is formed by seven scoria cones and lava flows, of andesite-basaltic andesite composition. The field was formed by volcanism contemporaneous with the ignimbrite volcanism of the APVC, with Cerro Guacha and La Pacana calderas being located nearby.
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In the Puna, extension appears to have begun between 10 and 5 million years ago. A basin formed at Pasto Ventura during the Miocene and was filled with thick sedimentary deposits; it is the only exposed basin in the Puna. The high plateau is volcanically active, with various stratovolcanoes, monogenetic volcanoes, lava domes, calderas and associated ignimbrites including Cerro Galán. Some of these volcanic centres are aligned along northwest-southeast trending lineaments.
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La Pacana together with the Cerro Guacha and Purico Complex calderas forms the La Pacana Complex. Guacha experienced two major eruptions, of which one occurred 4.1 million years ago. The Purico complex began erupting 1.3 million years ago; it is the youngest centre of the La Pacana Complex with the youngest eruptions occurring during the Holocene. Additional volcanic centres west and southwest of La Pacana are Acamarachi, Láscar, Colachi and Cordón de Puntas Negras.
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East face of Mount Silverthrone Like other calderas, Silverthrone formed as a result of emptying the magma chamber beneath the volcano. If enough magma is erupted, the emptied chamber will not be able to support the weight of the volcanic edifice above it. A roughly circular fracture—a "ring fault"—develops around the edge of the chamber. These ring fractures serve as feeders for fault intrusions that are also known as ring dikes.
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The Gran Cratere Vulcano () or Vulcan is a small volcanic island in the Tyrrhenian Sea, about north of Sicily and located at the southernmost end of the seven Aeolian Islands.Vulcano, Sicily 8 Hidden Italian Islands Where You Can Escape the Crowds. Retrieved 24 July 2019. The island is in area, rises to above sea level, and it contains several volcanic calderas, including one of the four active volcanoes in Italy that are not submarine.
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Several have nested or cross- layered calderas and pit craters (29 in total), many of which push into the flank of the volcanoes. In several cases, newer volcanic structures have all but erased older ones. In addition to all this the seamounts are pocketed by multiple small cones, and are littered by debris ranging far and wide from the range. There is evidence of erosional activity throughout, with erosional valleys and landslide debris visible.
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Guacha caldera is also closely linked to the neighbouring La Pacana caldera. The Guacha caldera forms a structure with the neighbouring Cerro Panizos, Coranzulí and Vilama calderas associated with a fault named the Lípez lineament. Activity along this lineament commenced with the Abra Granada volcanic complex 10 mya ago and dramatically increased more than a million years later. Volcanic activity is linked to this fault zone and to the thermal maturation of the underlying crust.
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Isabela's rich bird, animal and marine life is beyond compare. Isabela is home to more wild tortoises than all the other islands. Isabela's large size and notable topography created barriers for the slow-moving tortoises; apparently the creatures were unable to cross lava flows and other obstacles, causing several different sub-species of tortoise to develop. Today, tortoises roam free in the calderas of Alcedo, Wolf, Cerro Azul, Darwin, and Sierra Negra.
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Since then, the land has been through a string of exchanges between private owners and business enterprises. Most notably, it was owned by Frank Bond in the 1930s. Mr. Bond, a businessman based in nearby Española, ran up to 30,000 sheep in the calderas, significantly overgrazing the land and causing damage from which the watersheds of the property are still recovering. The land was purchased by the Dunigan family from Abilene, Texas in 1963.
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Also, eruptions may have taken place due to a magma reservoir at the base of the crust. This forms a dome, possibly the same morphology of a shield volcano where calderas universally are known to form. Although caldera-like structures are rare on the Moon, they are not completely absent. The Compton-Belkovich Volcanic Complex on the far side of the Moon is thought to be a caldera, possibly an ash-flow caldera.
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Laguna Amarga and Laguna Verde are sometimes associated with the Vallecito ignimbrite instead. The formation of the Laguna Amarga volcanic centre was probably influenced by orogenic changes in the Andes which triggered the formation of fractures in the crust. The Laguna Amarga caldera has a diameter of and is linked to the Laguna Escondida caldera. The Laguna Verde ignimbrite was erupted 4-3 mya ago and is associated with these two calderas.
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Street scenery at Pematangsiantar in 1910s Dutch house in Pematangsiantar (1923) Aerial view of Siantar in 1938 Pematang Siantar Zoo Pematangsiantar is 50 kilometres from Lake Toba on the Trans-Sumatran Highway. Lake Toba is one of the largest volcanic calderas in the world, and a major tourism destination. It is common to see tourists stopping over in Pt. Siantar. Siantar is famous for Batak culture, 'Batik' and 'Ulos' fabric, and Batak foods.
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The central caldera measures about 24 km across and 3.4 km deep and is the youngest of the collapse structures.Mouginis-Mark, P.J.; Harris, A.J.L.; Rowland, S.K. (2007). Terrestrial Analogs to the Calderas of the Tharsis Volcanoes on Mars in The Gelogoy of Mars: Evidence from Earth-based Analogs, M. Chapman, Ed.; Cambridge University Press: Cambridge, UK, pp. 80–81. Crater counting indicates that the central caldera is about 100 million years (Myr) old.
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Circular calderas in the Mount Edziza volcanic complex were formed as a result of emptying the magma chamber beneath a volcano. If enough magma is erupted, the emptied chamber will not be able to support the weight of the volcanic edifice above it. A roughly circular fracture— a "ring fault"— develops around the edge of the chamber. These ring fractures serve as feeders for fault intrusions that are also known as ring dikes.
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These so-called "hotspots", for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core–mantle boundary, 3,000 km deep in the Earth. Volcanoes are usually not created where two tectonic plates slide past one another. Sabancaya volcano erupting, Peru in 2017 Cordillera de Apaneca volcanic range in El Salvador. The country is home to 170 volcanoes, 23 which are active, including two calderas, one being a supervolcano.
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Its main feature is a NE-SW-oriented rift- like fracture set connecting two summit calderas. There is also a structure which links the northern caldera and ridge system to Idem Kuva corona located NW of Gula Mons. Radially spreading lava flows which have digitate and broad sheet-like forms extend from the summit, including radar-dark flows which overlay several older lava deposits. Radial and circumferential fractures are present on the flanks.
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The calderas are breached to the east by the Haya-kawa canyon. Mount Ashigara is a parasitic cone. The latest magmatic eruptive activity at Hakone occurred 2,900 years ago. It produced a pyroclastic flow and a lava dome in the explosion crater, although phreatic eruptions took place as recently as the 12–13th centuries AD. According to the nearby Hakone Shrine, the Komagatake peak has been the object of religious veneration since ancient times.
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Only grass, moss and lichen survive here. Especially species-rich are glacial cirques such as the Obří důl, Labský důl and Důl Bílého Labe on the south side and the dramatic Śnieżne Kotły, Kocioł Łomniczki and the calderas of mountain lakes Wielki Staw and Mały Staw on the north side of the main ridge. The species- richest areas are called zahrádka ("garden"). There are about 15 in Krkonoše, for example Čertova zahrádka und Krakonošova zahrádka.
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The lake owes its origin to intense volcanic and tectonic activity from 600,000 to 40,000 years before present, which created many small volcanoes in the Sabatino territory. The main magma chamber was situated under the present lake of Bracciano. Its collapse created the depressed area now occupied by the lake, which is not a crater lake. Some small craters and calderas are still recognisable around the lake and in the immediate vicinity (Martignano, Baccano, Sacrofano).
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In addition, several granitic stocks are found there. The Crucero and Picotani field may have been one single volcanic field once, covering a surface area of . The total volume of ignimbrites in the field is about , not counting eroded material. Some calderas and fissures that may be the source of the Macusani rocks lie south of the Macusani basin, in the Nevado La Huana area; no caldera has been directly imaged though.
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Northeast face of Mount Silverthrone Very little is known about Silverthrone's eruptive history. However, as at other calderas, eruptions at Silverthrone are explosive in nature, involving viscous magma, glowing avalanches of hot volcanic ash and pyroclastic flows. The source magma of this rock is classified as acidic, having high to intermediate levels of silica, as in rhyolite, dacite, and andesite. Andesitic and rhyolitic magma are commonly associated with the two forms of explosive eruptions called Plinian and Peléan eruptions.
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Sollipulli (; in the Mapuche language) is an ice-filled volcanic caldera and volcanic complex, which lies southeast of the small town of Melipeuco in the La Araucanía Region, Chile. It is part of the Southern Volcanic Zone of the Andes, one of the four volcanic belts in the Andes chain. The volcano has evolved in close contact with glacial ice. It differs from many calderas in that Sollipulli appears to have collapsed in a non-explosive manner.
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Batu Gantung (Hanging stone) in Lake Toba Map of the lake The Toba caldera complex in North Sumatra comprises four overlapping volcanic craters that adjoin the Sumatran "volcanic front". At it is the world's largest Quaternary caldera, and the fourth and youngest caldera. It intersects the three older calderas. An estimated of dense-rock equivalent pyroclastic material, known as the youngest Toba tuff, was released during one of the largest explosive volcanic eruptions in recent geological history.
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As eruptions become more and more frequent at the end of the preshield stage, the composition of the lava erupted from the Hawaiian volcano changes from alkalic basalt to tholeiitic basalt and the volcano enters the submarine phase of the shield stage. In this phase, the volcano continues to erupt pillow lava. Calderas form, fill, and reform at the volcano's summit and the rift zones remain prominent. The volcano builds its way up to sea level.
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The Central Andes formed first during the Paleozoic–Eocene and were worn down by erosion during the Oligocene. The recent volcanic activity started during the Miocene and includes major ignimbrite eruptions of dacitic to rhyolitic composition; such large eruptions began 23 million years ago and caused the formation of calderas like Galán. The total volume of this formation exceeds . Stratovolcanoes also began to form 23 million years ago, although most were constructed in the last 6 million years.
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In September 2007, the International Astronomical Union (IAU) renamed the volcano Alba Mons (Alba Mountain), reserving the term Alba Patera for the volcano's two central depressions (calderas). Nevertheless, the entire volcano is still commonly called Alba Patera in the planetary science literature.A Google Scholar search of the astronomy and planetary science literature from 2007 to 2011 reveals 106 uses of Alba Patera versus 5 for Alba Mons (accessed May 7, 2011). MOLA topographic map of Alba Mons and surroundings.
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Yellowstone National Park is a thermally active area with an extensive system of hot springs, fumaroles, geysers, and mudpots. There are also several hydrothermal explosion craters, which are not to be confused with calderas, which are collapse features. Eight of these hydrothermal explosion craters are in hydrothermally cemented glacial deposits, and two are in Pleistocene ash- flow tuff. Each is surrounded by a rim composed of debris derived from the crater, 30 to 100 feet high.
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To its north-northeast lies a large and deep caldera that is elongated in the northwest-southeast direction; the Monowai volcano as a whole has a similar elongation. The caldera appears to consist of two nested calderas, the outer of which is the largest in the northern Kermadec arc with a surface area of ,. although an origin as one single long-lived caldera is also possible. This caldera is the largest in the Kermadec volcanic arc.
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They were among the few surface features visible as the spacecraft entered orbit during a global dust storm. Appearing as faint spots through the dusty haze, they were informally christened North Spot, Middle Spot, and South Spot. A fourth spot corresponding to the albedo feature Nix Olympica was also visible and later named Olympus Mons. As the dust cleared, it became obvious that the spots were the tops of enormous shield volcanoes with complex central calderas (collapse craters).
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The CVZ extends over the Altiplano-Puna where calc-alkaline volcanism has been ongoing since the Miocene. Characteristic for the CVZ are the large fields of ignimbritic volcanism and associated calderas, chiefly in the Altiplano-Puna volcanic complex. In the southern part of the CVZ such volcanic systems are usually small and are poorly studied. During the Neogene, volcanism commenced in the Maricunga belt and eventually shifted to its present-day location in the Western Cordillera.
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The late mafic eruption products and the Cerro Blanco volcanics are geologically classified as making up the "Purulla Supersynthem". From the Miocene to the Pliocene the La Hoyada volcanic complex was active southwest of Cerro Blanco; afterwards came a 2 million years long hiatus. Cerro Blanco overlies this volcanic complex and outcrops of La Hoyada are found inside and around the calderas. The basement is formed by metamorphic and sedimentary rocks of Paleozoic to Mesozoic age.
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Andesitic eruptions tend to form steep stratovolcanoes, including mountains such as Ruapehu, Tongariro and Taranaki, islands such as Little Barrier, White and Raoul Islands, or submarine seamounts like Monowai Seamount. Rhyolitic eruptions with large amounts of water tend to cause violent eruptions, producing calderas, such as Lake Taupo and Lake Rotorua. New Zealand also has many volcanoes which are not clearly related to plate subduction including the extinct Dunedin Volcano and Banks Peninsula, and the dormant Auckland Volcanic Field.
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The last eruption, of Tarawera and Lake Rotomahana in 1886, was a relatively minor eruption, which was thought to have destroyed the famous Pink and White Terraces, and covered much of the surrounding countryside in ash, killing over 100 people. In 2017 researchers rediscovered the locations of the Pink and White Terraces using a forgotten survey from 1859. Many lakes around Rotorua are calderas from rhyolitic eruptions. For example, Lake Rotorua erupted around 13,500 years ago.
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The Teton fault is unique in that it dips or slopes to the east. The majority of major faults in the Basin and Range province dip to the west. The unique dip of the Teton fault can be explained by the subsidence of the Snake River Plain. The Snake River Plain is located to the west of the Teton fault and was formed by the migration of the Yellowstone hotspot forming prehistoric calderas across southern Idaho.
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Raoul Island, looking towards the minor islands northeast Two Holocene calderas are found at Raoul. The older caldera, which cuts the center of Raoul Island, is about long and wide respectively. Denham caldera, formed during a major dacitic explosive eruption about 2200 years ago, truncated the western side of the island and is long and wide respectively. Its long axis is parallel to the tectonic fabric of the Havre Trough that lies west of the volcanic arc.
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The Juan de Fuca Plate is being subducted under the North American Plate, generating gradual, diverse volcanism. The Cascade Range was produced by convergence of the North American Plate with the subducting Juan de Fuca Plate. Active volcanism has taken place for approximately 36 million years; the nearby Challis Range features complexes as old as 55 mya. Most geologists believe that activity in the Cascades has been relatively intermittent, producing up to 3,000 volcanic calderas at a time.
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During the Tertiary, these were overlaid by a total of deposits from the ignimbritic Capillune, Llallahui and Sencca Formations. The emplacement of the Capillune Formation continued into the earliest Pliocene; subsequently the Plio-Pleistocene Barroso Group was deposited, which includes the composite volcano that hosts Huaynaputina but also ignimbrites that appear to come from calderas. One such caldera is located just south of Huaynaputina. The late Pleistocene to Holocene volcanoes have been classified as the Arequipa Volcanics.
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A thermal event in the volcano in 1847 caused a meltwater flood on the Cachapoal River. The southern slope features the Universidad Glacier, which forms the Rio San Andrés which drains into the Tinguiririrca River. With a snowline altitude of , it was the second longest glacier in Central Chile in 1958, but since then glaciers in the region have shrunk. The edifice is mainly constructed by lava flows that bury parts of the calderas in the foot of the volcano.
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The plain is a depression, sinking under the weight of the volcanic rocks that formed it, through which the Snake River winds. Other observable volcanic features in the plain include: the Menan Buttes, the Big Southern Butte, Craters of the Moon, the Wapi Lava Field and Hell's Half Acre. These calderas are in an area called Island Park that is known for beautiful forests, large springs, clear streams, waterfalls, lakes, ponds, marshes, wildlife, and fishing. Harriman State Park is located in the caldera.
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Ann G. Harris, et al., The Geology of National Parks,(Dubuque, Iowa: Kendall-Hunt, 2004) Olivine basalts were extruded from a N. 70° E. trending rift zone, oriented along the current Afono and Masefay bays of Tutuila, in the Pliocene or earliest Pleistocene. The Masefau dike complex and talus breccias are remnants of this rifting. Development of the Taputapu, Pago, Alofau, and Olomoana shield domes followed long parallel fissures followed, but when the Pago and Alofau summits collapsed, calderas were formed.
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An earlier phase of volcanism in the Cordillera de la Costa commenced in the Jurassic but is considered separate from the Central Volcanic Zone magmatism proper. After an erosional hiatus during the Oligocene, volcanic arc activity increased during the Miocene and culminated in a phase of strong ignimbrite eruptions, which originated in calderas. This phase was associated with a substantial thickening of the crust in the Central Andes. During the Pleistocene ignimbrite volcanism waned again and stratovolcanoes began to develop.
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La Pacana has a diameter of with a north-south elongation. This is one of the best exposed and largest calderas in the world; the largest caldera known is Toba in Sumatra with a maximum length of . La Pacana might not be a single caldera; some reconstructions imply that the northern parts of the caldera are actually a separate collapse structure. The floor of the caldera lies at an elevation of , the central uplift and the caldera rim are higher and reach .
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Aguas Calientes caldera is a roughly circular caldera limited on the western and eastern side by north-south trending fault systems. Two superimposed calderas form the volcanic system. Cerro Verde inside the caldera is a dome formed by the uplifting of the Verde ignimbrites in the caldera after their deposition and cooling. Cerro Aguas Calientes was formed in the same way from the Tajmar ignimbrites, conclusions based in both cases on the outward dip of the ignimbrites contained in the domes.
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Piz Julier (German, ) is a mountain of the Albula Alps, overlooking the Julier Pass, in the Swiss canton of Graubünden. With a height of 3,380 metres above sea level, Piz Julier is the second highest peak (after Piz Calderas) of the group between the Julier Pass and the Albula Pass. Piz Julier can be summited by experienced hikers. From the heights of St. Moritz, a trail leads to Fuorcla Albana (2,870 metres), the pass between Piz Julier and Piz Albana.
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Most of the volcanoes have gently sloping plateaus, in conformity with their low shield volcano–like profiles, which have been heavily modified by multiple calderas. These are generally very shallow, having been formed then filled almost completely by younger flows, leaving only parts of the rims untouched. Some also have landslide debris deposits near the base of the caldera rims, and several have since been breached (their sides have collapsed). Small cones lay along the seafloor surrounding the main formation.
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Mount Batur (Gunung Batur) is an active volcano located at the center of two concentric calderas north west of Mount Agung on the island of Bali, Indonesia. The south east side of the larger 10×13 km caldera contains a caldera lake. The inner 7.5-kilometer-wide caldera, which was formed during emplacement of the Bali (or Ubud) ignimbrite, has been dated at about 23,670 and 28,500 years ago. The first documented eruption was in 1804 and the most recent was in 2000.
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Many rugged peaks in the North Cascades owe their prominence to this baking. The rocks holding up many such North Cascade giants, as Mount Shuksan, Mount Redoubt, Mount Challenger, and Mount Hozomeen, are all partly recrystallized by plutons of the nearby and underlying Chilliwack batholith. The Garibaldi Volcanic Belt is the northern extension of the Cascade Arc. Volcanoes within the volcanic belt are mostly stratovolcanoes along with the rest of the arc, but also include calderas, cinder cones, and small isolated lava masses.
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Most of the Silverthrone Caldera's eruptions in the Pacific Range occurred during the last ice age and was episodically active during both Pemberton and Garibaldi Volcanic Belt stages of volcanism. The caldera is one of the largest of the few calderas in western Canada, measuring about long (north-south) and wide (east-west). The last eruption from Mount Silverthrone ran up against ice in Chernaud Creek. The lava was dammed by the ice and made a cliff with a waterfall up against it.
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The term "patera", like other terms of planetary nomenclature, describes only the external view of the feature, but not its origin or geological structure. Majority of paterae of Venus, Mars and Io are volcanic craters or calderas, but some others (like Orcus Patera on Mars), probably, are impact craters. At least some of paterae on Triton and the only (as for 2016) named patera of Titan, Sotra Patera, most probably, have cryovolcanic origin. Some authors include low depth in defining criteria of paterae.
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The older Nemo calderas appear to predate the last glaciation, while the younger one is post-glacial in age. Nemo I formed 40,000 - 45,000 years ago and Nemo III 25,000 - 24,500 or 26,000 years ago; a radiocarbon date of 24,500 ± 740 years ago has been obtained on it. Nemo Peak proper formed about 9,050 ± 100 or 9,130 ± 140 radiocarbon years ago. Holocene volcanic activity includes the emission of tephra and lava flows with eruptions every 1,400 - 1,200 years since 3,800 years before present.
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Along with the Fernandina Island volcano, the western Galapagos volcanoes have similar structures that differ from the volcanoes in the eastern part of the archipelago. The western volcanoes are higher and have larger calderas than those to the east, they are also shaped like an upturned soup bowl. Wolf reaches a height of over 1700 metres; the caldera is 6 by 7 km and has a depth of 700m. Only Cerro Azul has a caldera of similar depth in the Galapagos.
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Cerro Guacha is a Miocene caldera in southwestern Bolivia's Sur Lípez Province. Part of the volcanic system of the Andes, it is considered to be part of the Central Volcanic Zone (CVZ), one of the three volcanic arcs of the Andes, and its associated Altiplano-Puna volcanic complex (APVC). A number of volcanic calderas occur within the latter. Cerro Guacha and the other volcanoes of that region are formed from the subduction of the Nazca plate beneath the South America plate.
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Evacuation of the volcano's magma chamber resulted in the failure of one or more centrally located calderas. It is divided into Precaldera, Dome Forming, Intra Caldera and Shield Forming assemblages. The Precaldera Assemblage is best exposed on the east side of Pipe Organ Mountain where it contains a bedded pile over 300 m thick of weakly consolidated, moderately to extremely different, pyroclastics, flows and deposits of uncertain origin. Colours range from mottled green to grey, yellow, ochre, red and white.
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Tres Garantías , is in the town of Othón P. Blanco, which is in the southern state of Quintana Roo. The town is located at coordinates . And San Jose de la Montana in the north, and Tomás Garrido in communities around Nicolas Bravo are located, Calderas, New Guadalajara (La Union) and The Corozalito in the south. It is possible to Tres Garantías by a 36 km paved road that connects with Federal Highway 186, which links the cities of Escárcega and Chetumal.
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Morphologically, centers include calderas, cinder cones, stratovolcanoes and small isolated lava masses. Due to repeated continental and alpine glaciations, many of the volcanic deposits in the belt reflect complex interactions between magma composition, topography, and changing ice configurations. The most recent major catastrophic eruption in the Garibaldi Volcanic Belt was an explosive eruption of the Mount Meager massif about 2,350 years ago. It was similar to the 1980 eruption of Mount St. Helens, sending an ash column about 20 km into the stratosphere.
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It is the source of the Huckleberry Ridge Tuff that is found from southern California to the Mississippi River near St. Louis. This supereruption occurred 2.1 million years BP and produced 2500 km3 of ash. The Island Park Caldera is sometimes referred to as the First Phase Yellowstone Caldera or the Huckleberry Ridge Caldera. The youngest of the hotspot calderas, the Yellowstone Caldera, formed 640,000 years ago and is about 34 miles (55 km) by 45 miles (72 km) wide.
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One of the specific features of the Retezat mountains is the widespread presence of glacier lakes. Approximately 38% of the glacier lakes of Romania are found here, on the bottom of calderas, grouped in lake clusters or isolated, and are one of the biggest tourist attraction of the park. Within the massiff limits, there are 58 permanent glacier lakes, between 1700 m and 2300 m. Some sources mention over 80 lakes, but here are most likely included the temporary ones as well.
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Ascraeus Mons in the north, has a complex set of internested calderas and a long history of eruption that is believed to span most of Mars' history. The three Tharsis Montes are about apart. They show a distinctive northeast–southwest alignment that has been the source of some interest. Ceraunius Tholus and Uranius Mons follow the same trend to the northeast, and aprons of young lava flows on the flanks of all three Tharsis Montes are aligned in the same northeast–southwest orientation.
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Though the surface rocks of the Earth have cooled enough to solidify, the outer core of the planet is still hot enough to remain liquid. Energy is still being released; volcanic and tectonic activity has pushed rocks into hills and mountains and blown them out of calderas. Meteors also create impact craters and surrounding ridges. However, if the energy release from these processes halts, then they tend to erode away over time and return toward the lowest potential-energy curve of the ellipsoid.
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There are many large volcanoes with relatively frequent eruptions. There are also several very large calderas, with the most obvious forming Lake Taupo. Taupo has a history of incredibly powerful eruptions, with the Oruanui eruption 26,500 years ago ejecting of material and causing the downward collapse of several hundred square kilometres to form the lake. The last eruption occurred and ejected at least 100 cubic kilometres of material, and has been correlated with red skies seen at the time in Rome and China.
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Solidified lava flows long give the caldera its flower-like appearance. The flows are a lighter tone of gray in the radar data because the lava is blockier in texture and consequently returns more radar waves. Much of the lava, which was evacuated from the chamber, probably traveled to other locations underground, while some of it may have surfaced further south. This is unlike calderas on Earth, where a rim of lava builds up in the immediate vicinity of the caldera.
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"The United Nations lacks respect for the indigenous people of Peru and Bolivia who have used the coca leaf since forever," said Peruvian Congresswoman Maria Sumire. "For indigenous people, coca is a sacred leaf that is part of their cultural identity," she said. In December 2005, the Paeces – a Tierradentro (Cauca) indigenous community – started to produce a carbonated soft drink called "Coca Sek". The production method belongs to the resguardos of Calderas (Inzá) and takes about of coca per 3,000 produced bottles.
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The calderas on Sierra Negra and Alcedo have active fault systems. The Sierra Negra fault is associated with a sill 2 km below the caldera. The caldera on Fernandina experienced the largest basaltic volcano collapse in history, with the 1968 phreatomagmatic eruption. Fernandina has also been the most active volcano since 1790, with recent eruptions in 1991, 1995, 2005, and 2009, and the entire surface has been covered in numerous flows since 4.3 Ka. The western volcanoes have numerous tuff cones..
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Tweed Volcano in New South Wales is a large shield volcano that was formed by the hotspot about 23 million years ago and has one of the biggest erosion calderas in the world. A number of the volcanoes in the province have erupted since Aboriginal settlement (46,000 BP). The most recent eruptions were about 5,600 years ago, and memories of them survive in Aboriginal folklore. These eruptions formed the volcanoes Mount Schank and Mount Gambier in the Newer Volcanics Province.
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Unlike impact craters, pit craters are rimless, often irregularly shaped, steep-sided, and often display no associated ejecta or lava flows. These pit craters are thought to be evidence of shallow volcanic activity and may have formed when retreating magma caused an unsupported area of the surface to collapse, creating a pit. They are analogs of Earth's volcanic calderas. Pit-floor craters may provide an indication of internal igneous processes where other evidence of volcanic processes is absent or ambiguous.
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Ancient lava flows in turn may be considered a form of hydrological modification, which may be confounded with other fluids. Io currently has lava calderas and lakes. Fluid modification may have occurred on bodies as small as Vesta; hydration in general has been observed. If fluids include groundwater and vapor, the list of bodies with hydrological modification includes Earth, Mars, and Enceladus, to a lesser extent comets and some asteroids, likely Europa and Triton, and possibly Ceres, Titan, and Pluto.
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Cerro Bitiche is part of a number of mafic volcanic centres associated with the Altiplano-Puna volcanic complex. The two major calderas La Pacana and Cerro Guacha are close to Cerro Bitiche, the eastern margin of Guacha's oldest caldera is located just east of Bitiche. Ordovician marine sequences form the tectonic basement of the area, but most of it is covered by ignimbrites and lavas between 8.5-4 million years old. The volcanic field covers a surface area of , including lava flows and scoria cones.
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Volcanic centres include calderas and associated large ignimbrites, lava domes and stratovolcanoes; among the better-researched volcanoes are Galan, Nevados de Payachata, Ollague, Purico Complex, San Pedro–San Pablo, La Pacana, Tata Sabaya and Tumisa. Over 44 volcanoes in the region are considered potentially active, with a number of young volcanoes featuring fumarolic or hydrothermal activity. Guallatiri, for example, features fumarolic activity that is visible in satellite images. Also fumarolically active are: Sabancaya, El Misti, Ubinas, Tacora, Isluga, Irruputuncu, Olca, Ollague, San Pedro, Putana and Lastarria.
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Chã das Caldeiras (“Plain of the Calderas”) is a small community of approximately 700 inhabitants in the crater of the volcano Pico do Fogo on the island of Fogo, Cape Verde. The village consists of two main parts: Portela and Bangaeira, founded in 1920 and 1917, respectively.Parc Naturel de Fogo – Chã das Caldeiras, Tentative list Unesco World Heritage sites At an elevation of about 1,700 meters, it is the highest village in Cape Verde. It is part of the municipality of Santa Catarina do Fogo.
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In comparison to Villarrica, Quetrupillán has been less active and its eruptions were also smaller than Villarrica's, with no large pyroclastic flows found at Quetrupillán. Quetrupillán is a high composite stratovolcano with a wide caldera and a shrinking glacier cover. The volcano contains in total two nested calderas, the larger of which is wide, and a field of lava domes, maars and pyroclastic cones that occupy a surface of . These subsidiary vents include the scoria cone Huililco, the Volcanes de Llancahue and the Volcanoes de Reyehueico.
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Santa Ana volcano with Izalco to the far left, Cerro Verde center and San marcelino vents in the foreground. The summit of Santa Ana features four nested calderas and volcanic craters, with the innermost containing a small crater lake. Collapse of the summit during the late Pleistocene (inferring from underlying soil samples, the upper age limit is no more than 57,000 years ago) produced a massive debris avalanche that reached the Pacific Ocean, forming the Acajutla Peninsula. Subsequent eruptions have largely rebuilt the edifice.
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Nevado de Acay lies northeast just outside the caldera margin, and the town of San Antonio de los Cobres only about northwest. The cities of Salta and Jujuy lie about east of Negra Muerta. The region has an arid climate, thus geological features are often buried beneath uneroded rocks and difficult to access. The south Central Andes in the past were the site of large scale dacitic ignimbrite-forming eruptions and the formation of calderas, linked to the interaction between a subducting slab and the overlying crust.
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NIMS (near-infrared mass spectrometer) is used to interpret thermal data. The floor of the patera is covered in lava, but the images cannot discern whether the green is a primary or secondary feature. The lava on the floor of the patera are thought to mimic morphologies similar to terrestrial calderas such as Kilauea Caldera in Hawaii. This is supported by their tendency to inflate or pool up when they are secluded, and also how they drain back into vents, resulting from escaping gases in the magma.
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Aside from stratovolcanoes which are lined up in the Western Cordillera, the Altiplano-Puna volcanic complex is also a component of the Central Volcanic Zone and is formed by large calderas and lava domes such as La Torta. Of those units of Tocorpuri that have been sampled, most are andesitic with phenocrysts of amphibole, biotite, pyroxene and quartz. La Torta also has phenocrysts of sanidine and additional apatite and titanite. The main Tocorpuri volcano is partly covered by the Tatio ignimbrite, which is about 800,000 years old.
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La Estacion Theme Park (The Railway Station), including The Old Train Station and Railway Museum, is a historic and recreational complex located in the city of Aguascalientes, in the state of Aguascalientes, in Mexico. The State of Aguascalientes was at some point a major railway hub for Mexico, due to its central location between important cities. It was home to some of the largest workshops and warehouses in Latin America. When the workshops ceased its work, the calderas, machinery and old workshops remained abandoned.
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The terrain northeast-east from Cerro Blanco is covered by its ignimbrites and by Plinian fallout deposits which radiate away from the calderas. Cerro Blanco lies at the southwestern end of the Carachipampa valley, a volcano-tectonic depression flanked by normal faults which extends to Carachipampa. This depression appears to have formed in response to north-south tectonic extension of the Puna and is covered by volcanic deposits from Cerro Blanco. These volcanic deposits form the "Campo de Pedra Pomez" and extend away from the volcano.
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Large lava flow fields are described as flood-type lava that can be seen in fluctus fields. These are regions flooded with many low- viscosity volcanic flows from a single source that covers the area in a continuous flow field. Some flows may be radially distributed around a volcano of coronae as an apron, be fan-shaped, or sub-parallel in their orientation. Large flow fields may be sourced from large volcanoes, calderas, rift structures, or shield volcano fields and they are often associated with extensional environments.
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Ksudach () (also known as Vonyuchy Khrebet Volcano) is a stratovolcano in southern Kamchatka, Russia. The last eruption of Ksudach was in March 1907, on or around 28 March, which was one of the largest ever recorded in Kamchatka, with a Volcanic Explosivity Index of 5 and a volume of ejected ash at . The 1907 eruption sent ash high into the atmosphere which was transported by the jet stream, leaving North America east of the Rocky Mountains unseasonably cold. The summit area comprises overlapping calderas.
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The volcanic activity of Mars is concentrated in two major provinces: Tharsis and Elysium. Each province contains a series of giant shield volcanoes that are similar to what we see on Earth and likely are the result of mantle hot spots. The surfaces are dominated by lava flows, and all have one or more collapse calderas. Mars has the largest volcano in the Solar System, Olympus Mons, which is more than three times the height of Mount Everest, with a diameter of 520 km (323 miles).
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Laguna Amarga is a caldera and associated ignimbrite in the Andes of northwestern Argentina. Laguna Amarga is part of the southern Central Volcanic Zone and one among several Miocene-Pliocene-Pleistocene volcanic centres of this volcanic region. The formation of magma chambers and thus of large volcanic systems has apparently been influenced by tectonic changes. The Laguna Amarga caldera is associated with the Cordillera Claudio Gay faults together with the Laguna Escondida and Wheelwright calderas, all of which are between 6.5 and 4 mya old.
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The New Senator Caldera is a large Archean caldera complex within the heart of the Blake River Megacaldera Complex, Quebec, Canada. It has a diameter of 15-30 kilometers and is made of thick massive mafic sequences. The caldera complex has inferred to be a subaqueous lava lake during the early stages of the caldera's development.ASH FALL: Newsletter of the Volcanology and Igneous Petrology Division Geological Association of Canada Retrieved on 2007-09-21 Gabbro sills represent lava lakes, which are common in mafic summit calderas.
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The rocks are the exposed portion of the western ridge of a submarine volcanic caldera, approximately in diameter at a depth of approximately .Christopher G. Newhall, Daniel Dzurisin: Historical Unrest at large Calderas of the World. Volume 1, U.S. Geological Survey Bulletin 1855, Washington 1988, p. 506; Bathymetric map around "Bayonnaise Rocks" based on Basic Map of the Sea (1:50.000, retrieved 2012-12-13). The above sea-level portion has a surface area of approximately 0.01 square kilometers, with a summit height of .
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Emi Koussi (also known as Emi Koussou) is a high pyroclastic shield volcano that lies at the southeast end of the Tibesti Mountains in the central Sahara, in the northern Borkou Region of northern Chad. The highest mountain of the Sahara, the volcano is one of several in the Tibesti range, and reaches an elevation of , rising above the surrounding sandstone plains. The volcano is wide and has a volume of . Two nested calderas cap the volcano, the outer one being about in size.
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Within it on the southeast side is a smaller caldera known as Era Kohor, about wide and deep. Numerous lava domes, cinder cones, maars, and lava flows are found within the calderas and along the outer flanks of the shield. Era Kohor contains trona deposits, and Emi Koussi has been studied as an analogue of the Martian volcano Elysium Mons. Emi Koussi was active more than one million years ago, but some eruptions may be more recent, and there is ongoing fumarolic and hot spring activity.
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Mount Waesche is part of the Executive Committee Range, which from north to south includes Mount Hampton, Mount Cumming with the parasitic vent Annexstad Peak, Mount Hartigan, Mount Sidley with Doumani Peak and Chang Peak-Mount Waesche. These mountains are all volcanic and feature ice-filled calderas, and many are paired volcanoes. Volcanic activity appears to be moving southward at a rate of . Seismic activity recorded in 2010 and 2011 south of Mount Waesche may indicate ongoing magmatic activity south of the youngest volcano.
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The Marysvale volcanic field is located in southwestern Utah, United States. One of the largest volcanic fields in the western United States, the Marysvale straddles the Colorado Plateau-Great Basin transition zone. Most igneous rocks belong to a middle Cenozoic (~32 to 22 million years old) calc-alkaline sequence, although about 5% are related to an upper Cenozoic (23 million years to Holocene) bimodal (basalt and rhyolite) sequence. The Marysvale contains a variety of volcanic features, including stratovolcanoes, calderas, lava domes, and cinder cones.
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The Rio Salado ignimbrite elsewhere crops out as two flow units, with varying colours, and close to El Tatio it is crystalline and densely welded. It was followed by the 8.3 million years old voluminous Sifon ignimbrite, which reaches a thickness of about in the graben. The Pliocene Puripicar ignimbrite reaches a similar thickness, and it was later downwarped by faulting. This strong ignimbrite volcanism is associated with activity of the Altiplano–Puna volcanic complex, which has produced dacite dominated large volume ignimbrites and sizable calderas, starting from the middle Miocene.
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There are approximately fifteen calderas known in the San Juan Volcanic Fields; however, it is possible that there are two or even three more in the region. The region began with many composite volcanoes that became active between 35 and 40 million years ago, with peak activity in the time period around 35-30 million years ago. Around this time the activity began to include explosive ash-flow eruptions. Many of these volcanoes experienced caldera collapse, resulting in the fifteen to eighteen caldera volcanoes in the region today.
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Yellowstone sits on top of three overlapping calderas A geological event such as massive flood basalt, volcanism, or the eruption of a supervolcano could lead to a so-called volcanic winter, similar to a nuclear winter. One such event, the Toba eruption, occurred in Indonesia about 71,500 years ago. According to the Toba catastrophe theory, the event may have reduced human populations to only a few tens of thousands of individuals. Yellowstone Caldera is another such supervolcano, having undergone 142 or more caldera-forming eruptions in the past 17 million years.
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Morphologically, centers include calderas, cinder cones, stratovolcanoes and small isolated lava masses. Due to repeated continental and alpine glaciations, many of the volcanic deposits in the belt reflect complex interactions between magma composition, topography, and changing ice configurations. The most recent major catastrophic eruption in the Garibaldi Volcanic Belt was from the Mount Meager massif 2,350 BP, which is Canada's most recent major catastrophic eruption. The Garibaldi Volcanic Belt contains 2 extra volcanic fields, the Franklin Glacier Complex and the Silverthrone Caldera, which lie 140 and 190 km northwest of the main volcanic belt.
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It covers an area of - of the Altiplano-Puna in Argentina, Bolivia and Chile and consists of a number of calderas, composite volcanoes and about of ignimbrite. Uturuncu lies at its centre but unlike Uturuncu most surrounding volcanic systems have been characterized by explosive eruptions, including several so-called "supereruptions" with volcanic explosivity indexes of 8 at Cerro Guacha, La Pacana, Pastos Grandes and Vilama. Over 50 volcanoes in the region are potentially active. Within the last two million years, the Laguna Colorada, Tatio and Puripica Chico ignimbrites were erupted in the surrounding terrain.
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Montefiascone caldera from the air, showing the rim. Vulsini, also known as Volsini volcano, Vulsini Volcanic District, Vulsini Volcanic Complex and the Vulsinian District, is a circular region of intrusive igneous rock in Lazio, Italy, about to the north northwest of Rome, containing a cluster of calderas known to have been active in recent geologic and historical times. Potentially they still are active. The Vulsinian region is one of dozens of intrusive circular regions, most smaller than the Vulsinian, arranged in a band from Campania through Lazio, called the Roman Comagmatic Province.
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Fogo Fogo has many yasis running the routes between São Filipe and Mosteiros, São Filipe and Chã das Calderas. Unlike many other islands, these buses depart at roughly the same time every day, and despite the presence of multiple vehicles running each route, passengers can find themselves stranded if they do not board a vehicle during the limited departure window. Yasis tend to depart Mosteiros headed to São Filipe around 6am, and tend to Depart São Filipe headed to Chã around noon. São Vicente Mindelo has a municipal bus service run by the company Transcor.
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Uganda has many opportunities for mountain climbing, hiking and nature walks. The Rwenzori Mountains, which are found at the border with the DRC, include the snowcapped Margherita Peak (5109 m), the highest Mountain Range in Africa and also one of the highest peaks. Mgahinga Gorilla National Park also includes three peaks, Mount Gahinga, Mount Sabyinyo, and Mount Muhavura, the highest peak in the national park. Mount Elgon, located in Eastern Uganda, can be used for hiking and climbing, and also has one of the largest calderas in the world.
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The IBA comprises the Piton des Neiges – Gros Morne volcanic massif, the highest land on Réunion with a peak elevation of over 3000 m and the meeting point of the island's three calderas of Cilaos, Mafate and Salazie. The summit area is mainly bare rock and scree, while the lower parts of the site, from about 2800 m down to 2000 m above sea level, are vegetated with native alpine shrubland. The site has a mountain hut but no permanent inhabitants and is used recreationally by hikers and climbers.
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These gaps are not static; the gap separating the Austral and the Southern Volcanic Zones has been moving northward for the past 15-20 million years. The Southern Volcanic Zone itself is subdivided into additional volcanic zones, the Northern, Transitional, Central and Southern Southern Volcanic Zone and contains over two calderas and over 60 volcanoes with Quaternary activity. More volcanoes in the neighbourhood of Mentolat include Melimoyu and Cay to the north, Maca and Cerro Hudson to the south, as well as several monogenetic volcanoes. South of Hudson, the Chile Rise subducts in the trench.
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The archipelago is an example of a soda-alkaline petrographic province, with a petrologic succession which is similar to that found in other Mid Atlantic islands. Mount Fogo is an active volcano which most recently erupted in 2014. Fogo's caldera is in diameter, the rim is at an elevation of with an interior cone rising to from the crater's floor level. Calderas probably result from the subsidence, following the partial evacuation of the magma chamber, of a cylindrical block into the supplying magma chamber, in this case lying at a depth of some .
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Map of the Long Valley Caldera Early winter in Long Valley, 2017 Long Valley Caldera is a depression in eastern California that is adjacent to Mammoth Mountain. The valley is one of the Earth's largest calderas, measuring about long (east-west), wide (north-south), and up to deep. Long Valley was formed 760,000 years ago when a very large eruption released hot ash that later cooled to form the Bishop tuff that is common to the area. The eruption emptied the magma chamber under the area to the point of collapse.
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The central Colorado volcanic field (CCVF) is a volcanic field in Park County, Colorado. It is located in the southern Rocky Mountains and covered a roughly triangular area centered on the Thirtynine Mile volcanic area and extending from the Sawatch Range southeast to the northern Sangre de Christo Range and the Wet Mountains and northeast to the southern Front Range south of Denver. The area covered by the volcanic products of the eruptions included some produced by at least ten volcanic centers or calderas. The field overlaps the San Juan volcanic field to the west.
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The volcanic complex has shaped the local landscape and produced a huge variety of volcanic landforms and products over the last 300,000 years. Cinder cones, lava domes, calderas and craters can be found in the area apart from the widest variety of volcanic rocks in all the Southern Zone, for example both primitive basalts and rhyolites. Cordón Caulle erupted shortly after the 1960 Valdivia earthquake, the largest recorded earthquake in history. Apart from this, the Puyehue-Cordón Caulle area is one of the main sites of exploration for geothermal power in Chile.
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Mount Hasan () is a volcano in Anatolia, Turkey. It has two summits, the high eastern Small Hasan Dagi and the high Big Hasan Dagi, and rises about above the surrounding terrain. It consists of various volcanic deposits, including several calderas, and its activity has been related to the presence of several faults in the area and to regional tectonics. Activity began in the Miocene and continued into the Holocene; a mural found in the archeological site of Çatalhöyük have been controversially interpreted as showing a volcanic eruption or even a primitive map.
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The deposits from this event are also known as Cerro Blanco Ignimbrite, as Ignimbrite of the second cycle or El Médano or Purulla Ignimbrite. Formerly these were dated to be 12,000 and 22,000 years old, respectively, and related to the Cerro Blanco and (potentially) Robledo calderas. Cerro Blanco is considered to be the youngest caldera of the Central Andes. With a volume of of tephra the 4.2 ka eruption has been tentatively classified as 7 in the volcanic explosivity index, making it comparable to the largest Holocene volcanic eruptions.
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With an estimated original volume of approximately , the Flat Landing Brook Formation incorporates the eruptive products of a supervolcano similar in size and eruption rates to the Taupo and Yellowstone calderas. It may also represent the largest supervolcanic eruption of the Paleozoic era. Most of the volcanic rocks were laid down during a timespan of possibly less than two million years. A region of coarse co-ignimbritic breccias in the Flat Landing Brook Formation (Grants Lake pyroclastics) is interpreted to represent the infill of a large caldera with a radius of about .
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Similar material, grading up into finer debris flows and possibly lahars, has been uncertainly known in the gap between Phacelia Peak and Calliope Mountain suggesting this area is the southern edge of the caldera. Alternatively, largely unsorted breccia and debris deposits exist on the ridge north of Saxifraga Peak, possibly indicating the main, or a subsidiary, caldera edge. The Shield Forming Assemblage contains a series of basalt and minor comendite eruptions, and is best exposed on Far Mountain and Mount Scot. The basalts issued from fissure vents primarily located peripheral to the calderas.
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Mount Malindang is a complex volcano located in the province of Misamis Occidental in the southern island of Mindanao, Philippines. It is the highest point in the province. The least studied mountain range was formed through several volcanic activities some of which could be historical, evident by the presence of two calderas, surrounded by high rock walls, cinder cones, dome volcano plugs, two sulfurous hot springs, and a crater lake named Lake Duminagat. The amphitheater structures have extensive distribution of volcanic rocks, carbonized wood that are found in pyroclastic deposits.
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Only some eruptions before the Neogene period (from 23 Mya to 2.58 Mya) are listed. Known large eruptions after the Paleogene period (from 66 Mya to 23 Mya) are listed, especially those relating to the Yellowstone hotspot, the Santorini caldera, and the Taupo Volcanic Zone. Active volcanoes such as Stromboli, Mount Etna and Kīlauea do not appear on this list, but some back- arc basin volcanoes that generated calderas do appear. Some dangerous volcanoes in "populated areas" appear many times: Santorini six times, and Yellowstone hotspot 21 times.
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Other ignimbritic volcanic systems are the Galan and Panizos calderas, as well as older Oligocene ignimbrites in Sur Lipez. Kari-Kari is part of a volcanic system with neighbouring Los Frailes volcanic system, which has been active starting from 25,000,000 to recent times over six phases, covering a surface area of . Kari-Kari is the earliest known caldera in the Eastern Cordillera. No volcanic ignimbrites younger than 3,800,000 million years are found in the Eastern Cordillera, although in the Frailes region volcanic activity has continued into the Holocene with the Nuevo Mundo volcano.
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The Toledo and Valles Calderas formed during eruptions 1.61 million and 1.2 million years ago, respectively. The caldera forming Toledo eruption formed the Otowi member of the Bandelier Tuff at 1.61 million years ago, which can be seen along canyon walls west of Valles Caldera, including San Diego Canyon. The younger Tshirege member of the Bandelier Tuff was formed during the Valles Caldera forming eruption at 1.25 million years ago. The now eroded and exposed orange-tan, light-colored Bandelier tuff from these events creates the stunning mesas of the Pajarito Plateau.
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The caldera wall of Santorini island. The caldera is composed of overlapping shield volcanoes, cut by at least four partially overlapping calderas, of which the oldest southern caldera was formed about 180,000 years before the present era (BP). The subsequent Skaros caldera was created about 70,000 years BP, and the Cape Riva caldera about 21,000 years BP. The current caldera was formed about 3600 years BP during the Minoan eruption. Palea Kameni and Nea Kameni were formed as a result of multiple, initially submarine eruptions at the center of the caldera.
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The army is larger than the other services combined with approximately 56,780 active duty personnel, consisting of six infantry brigades, a combat support brigade, and a combat service support brigade. The air force operates two main bases, one in the southern region near Santo Domingo and one in the northern region near Puerto Plata. The navy operates two major naval bases, one in Santo Domingo and one in Las Calderas on the southwestern coast, and maintains 12 operational vessels. The Dominican Republic has the largest military in the Caribbean region surpassing Cuba.
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Even small caldera-forming eruptions, such as Krakatoa in 1883 or Mount Pinatubo in 1991, may result in significant local destruction and a noticeable drop in temperature around the world. Large calderas may have even greater effects. When Yellowstone Caldera last erupted some 650,000 years ago, it released about 1,000 km3 of material (as measured in dense rock equivalent (DRE)), covering a substantial part of North America in up to two metres of debris. By comparison, when Mount St. Helens erupted in 1980, it released ~1.2 km3 (DRE) of ejecta.
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The "Serapium" or Macellum of Pozzuoli demonstrated the effects of bradyseism. Bradyseism is the gradual uplift (positive bradyseism) or descent (negative bradyseism) of part of the Earth's surface caused by the filling or emptying of an underground magma chamber and/or hydrothermal activity, particularly in volcanic calderas. It can persist for millennia in between eruptions and each uplift event is normally accompanied by thousands of small to moderate earthquakes. The word derives from the ancient Greek words "bradus", meaning 'slow', and "seism" meaning 'movement', and was coined by Arturo Issel in 1883.
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Off the western coast of South America, the oceanic Nazca Plate subducts beneath the South America Plate in the Peru-Chile Trench. Volcanism associated with subduction in the region has been ongoing since the Jurassic. Dehydration of the downgoing slab causes melts to form in the abovelying asthenosphere which drive the activity in the volcanic arc. East of the main volcanic arc of the Central Volcanic Zone the back-arc region has been volcanically active since the Oligocene, generating volcanic edifices ranging from small monogenetic volcanoes to large calderas with their ignimbrites.
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The Blake River Megacaldera Complex is a giant subaqueous caldera cluster or a nested caldera system that spans across the Ontario-Quebec border in Canada. The caldera complex is around 2.7 billion years old, consisting of a series of overlapping calderas of various ages and sizes. It lies within the southern zone of the Abitibi greenstone belt of the Superior craton and has an area of . The Blake River Megacaldera Complex has been a centre of major interest since 2006 with numerous excursions at the international, national and local level.
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The growth of the mountain was occasionally interrupted by major eruptions, leading to the collapse of the summit to form calderas. From about 35,000 to 15,000 years ago, Etna experienced some highly explosive eruptions, generating large pyroclastic flows, which left extensive ignimbrite deposits. Ash from these eruptions has been found as far away as south of Rome's border, to the north. Thousands of years ago, the eastern flank of the mountain experienced a catastrophic collapse, generating an enormous landslide in an event similar to that seen in the 1980 eruption of Mount St. Helens.
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In places, the depressions form sinuous channels with islands and other features suggestive of erosion by a fluid. Whether the channels were formed predominately by water or lava is still a topic of debate,For volcanic argument example, see For fluvial argument example, see though extensive study of analogous environments (e.g. Hawaii, the Moon, elsewhere on Mars) and morphologic features by multiple researchers has led to the conclusion that a volcanic origin is most probable.For example, see The caldera complex consists of a central caldera surrounded by four coalesced calderas.
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Lake Bolsena is at the center of the Vulsinii (or Vulsino) Volcanic District of the Roman Comagmatic Region. The lake formed when a circular area collapsed after the depletion of the underlying magmatic chamber that fed the whole volcanic district. Although it is generally known as a volcanic lake, like its southern neighbor Lake Bracciano it is not a crater lake nor it occupies a caldera. The major calderas of the area are found close to the lake's rim (Latera to the west and Montefiascone to the south east).
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Cooled lava flows preserved around the volcano keep a record of the recent eruptions. Before the Jala eruption, there is record of one major lava flow, called the Destiladero flow. During the 500 years after the Jala eruption, the volcano was at its most active, leaving record of six major lava flows: the Copales, El Cajón, Coapan I, Coapan II, El Norte, and Ceboruco flows, all before the Spanish arrived in 1521. The volcano remained active until the next major eruption in 1870, however volcanism was, for the most part, constrained within the calderas.
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Toney Mountain is an elongated snow-covered shield volcano, long and rising to at Richmond Peak, located southwest of Kohler Range in Marie Byrd Land, Antarctica. Toney Mountain is an elongated volcanic massif that rises from a basaltic lava plateau. A wide summit caldera tops the volcano, and is elongated in east-west direction; this orientation is shared with calderas on other volcanoes in Marie Byrd Land and reflects regional tectonic stress. The slopes of the volcano feature parasitic vents and glacial corries, and are much steeper north of the volcano than south of it.
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The Vulkanland Eifel Geopark () is a German national geopark in the Volcanic Eifel region that was established on 19 April 2005. Covering an area of 2,200 km², the geopark extends from the Belgian border in the west over the Eifel mountains to the River Rhine in the east. The countryside here which has been shaped by the volcanism of the past contains numerous maars, cinder cones, lava flows lava domes calderas and bubbling springs. The largest caldera was formed by the Laacher See volcano that last erupted about 13,000 years ago.
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It is located east of the Chile Trench within the Puna where the volcanic arc intersects a probably deep- seated structural area named the Archibarca corridor. Since the Eocene, underlying convergence and subduction of the Nazca plate at a speed of result in the volcanic activity of the Central Volcanic Zone (CVZ), the activity of fault zones and active deformation south of 23° S. Several large calderas lie in the CVZ, some of which (Galan, La Pacana) have erupted volumes of over . The area is uninhabited and remote.
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Thick tuffs were deposited in the Pago caldera, and the southern rim was buried by lavas composed of picritic basalts, andesites, and trachytes. Subsequent erosion in Early to Middle Pleistocene enlarged the calderas, the Pago River in particular carved a deep canyon, the forerunner of today's Pago Pago Bay. A submarine shelf formed from the erosional runoff, allowing for the development of coral reefs before the island was submerged 600 to 2000 feet. Sea level fluctuations continued in the Middle to Late Pleistocene. A barrier reef formed, was submerged 200 feet, before emerging 50 feet, leaving sea caves above sea level.
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The earliest hot tubs were calderas in which hot stones were placed to heat the water. Therma in Ikaria has been a very popular place particularly for hydrotherapy ever since the 4th century BC.Ikaria: The Ancient Spa of Therma in Ikaria Greece, Eastern Aegean, Greeka.com. The remains of wrecked marble bathtubs along with a pre-historic aqueduct that have been unearthed from this area bear ample testimony of the place's popularity in the ancient times. In 737 A.D., Japan's first onsen opened near Izumo, Shimane, and centuries later the first ryokan (inns) were built, offering food, accommodations, and soaking tubs called ofuro.
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The Silverthrone Caldera is a potentially active caldera complex in southwestern British Columbia, Canada, located over northwest of the city of Vancouver and about west of Mount Waddington in the Pacific Ranges of the Coast Mountains. The caldera is one of the largest of the few calderas in western Canada, measuring about long (north-south) and wide (east-west). Mount Silverthrone, an eroded lava dome on the caldera's northern flank that is high, may be the highest volcano in Canada. The main glaciers in the Silverthrone area are the Pashleth, Kingcome, Trudel, Klinaklini and Silverthrone glaciers.
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Aguas Calientes caldera lies in the northwestern Salta Province of Argentina, in the San Antonio de los Cobres district to the southeast of the town of the same name. Aguas Calientes caldera is part of the Central Volcanic Zone (CVC), which is located in southern Peru, northern Chile, southwestern Bolivia and northwestern Argentina in highlands over high. At least six potentially active calderas, 44 active major and 18 active minor volcanoes lie in this area, of which Lascar volcano is the most active. The largest eruption in historical times in the CVZ occurred in 1600 on Huaynaputina volcano in Peru.
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The central band is a mix of volcanic and sedimentary rocks of mid-to-late Ordovician age comprising the lavas and tuffs of the Borrowdale Volcanic Group, erupted as the former Iapetus Ocean was subducted beneath what is now the Scottish border during the Caledonian orogeny. The northern central peaks, such as Great Rigg, were produced by considerable lava flows. These lava eruptions were followed by a series of pyroclastic eruptions which produced a series of calderas, one of which includes present-day Scafell Pike. These pyroclastic rocks give rise to the craggy landscapes typical of the central fells.
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The latest activity occurred in 104 BC. The largest, the Bolsena caldera, which is roughly across, is filled with the waters of Lake Bolsena, which derive mainly from deep aquifers. Immediately to the northwest are the combined Latera and Vepe calderas, about by . Vepe, to the north of Lake Mezzano (a very small crater lake west of Lake Bolsena) is what is known as a nested caldera; it arose in the previously existing Latera Caldera. Italian routes SS74 and SS312 follow the rim from Valentano through Latera westward, turning off before Mezzano on the other side.
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On the Osa Peninsula, the Nicoya Complex preserves oceanic crust with basaltic lava, dolerite, gabbro, limestone, chert and argillite, obducted onto land before the Oligocene and then rearranged by Miocene wrench faults. In the Neogene the low angle subduction of the Cocos Plate led to volcanism in the now extinct Cordillera de Aguacate chain in the center of the country. The Valle Central basin formed as volcanism shifted northeastward in the Quaternary. In the Pleistocene, calderas ejected huge quantities of silica-rich ash, filling the Valle Central basin, affecting the Tarcoles Gorge and generating the Orotina debris fan at the coast.
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The highest and most rugged parts are the Sierra Nevada, the Sierra del Tapo-Caparo and the Sierra de Calderas, with the first peak close to 4 000 m above sea level inside Barinas, and the last one has a lot of valleys. The tables of Moromoy, El Curay and Parangula are landmarks that separate the high and low parts. Two large passes are found, both to the north: the pass of the valleys and the depression of the Santo Domingo River and the pass of the Boconó River valleys. In the Paleozoic, the Merida mountain range was formed as an island.
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The Alban Hills are the caldera remains of a quiescent volcanic complex in Italy, located southeast of Rome and about north of Anzio. The high Monte Cavo forms a highly visible peak the centre of the caldera, but the highest point is Maschio delle Faete approximately to the east of Cavo and taller. There are subsidiary calderas along the rim of the Alban Hills that contain the lakes Albano and Nemi. The hills are composed of peperino (lapis albanus), a variety of tuff that is useful for construction and provides a mineral-rich substrate for nearby vineyards.
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Mount Vesuvius, near the city of Naples in Italy, violently erupted in 79 AD. The last eruption of this stratovolcano occurred in March 1944. A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava, tephra, pumice and ash. 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.
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This created the typical bimodal volcanic signature of the Cassidy Group and Pussycat Groups; the Tollu Group is a bit different, and it is considered the product of the large granite calderas which were formed immediately after the Giles Complex magmatism. Giles (1980) and earlier mappers have assigned the MacDougall Formation, overlying Mummawarrawarra Basalt, intermediate Smoke Hill Volcanics and the Tollu Volcanics to the Bentley Supergroup. There has been little real study done on the Bentley Supergroup Volcanics since the 1960s. Geochemical and petrological observations are few and far between or lacking comprehensive rare earth and trace elements suites.
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The Central Volcanic Zone is home to more than a thousand volcanoes, of which 44 were active after glacial times. Many of these are part of the main volcanic arc, which consists of stratovolcanoes such as Coropuna, the Nevados de Payachata, Ojos del Salado and Ollagüe and frequently reach heights of above . The Central Volcanic Zone is also the site of a number of large calderas, such as Los Frailes, Kari- Kari, Pastos Grandes, Cerro Panizos, Cerro Guacha, Purico complex, Coranzulí, La Pacana, Aguas Calientes, Negra Muerta volcanic complex, Galán, Wheelwright caldera and Incapillo. The Vilama caldera is between and wide.
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Since 23 million years ago the Central Volcanic Zone has given rise to compound volcanoes, calderas and stratovolcanoes, which are formed mainly by andesitic or dacitic rocks. Ojos del Salado, a member of the Central Volcanic Zone, is the second tallest mountain in the Andes and the highest active volcano in the world. Further, the Maricunga volcanic belt in the same region is site of major precious metal deposits. The caldera is , or wide and deep, and is one of the best preserved circular structures of the southern Central Andes, as well as one of its largest.
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The Nili Tholus cinder cone in the Nili Patera caldera on Mars. Nili Patera is a 50 km diameter caldera at the center of the Syrtis Major Volcanic Complex. It and Meroe Patera located to the south are the primary named calderas within a nested caldera complex developed by multiple eruption and collapse events. In the Northeast quadrant of Nili Patera is a 630 m tall volcanic cone named Nili Tholus, on and around this cone is a light-tone lava flow of chemically evolved lava with multiple occurrences of relict silica sinter deposits created by a formerly active hot spring system.
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The Nature Park of Flores (), or simply or Nature Park of Flores (PNF) developed from the intention of better managing the protected areas of the island of Flores, and was instituted by the Secretaria Regional do Ambiente e do Mar (Regional Secretariate for the Environment and Oceans), of the Autonomous Regional Government of the Azores. Although there are several ecosystems and environmentally distinct, this nature reserve includes three principal areas (the calderas Funda and Rasa, the mountain region of Morro Alto and Pico da Sé and the islet of Maria Vaz), in addition to several protected areas.
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The size of the deformation area is comparable with the size of calderas such as Long Valley and Yellowstone. Likewise, such deformation patterns are mainly found in active caldera systems and in the case of Lazufre may be caused by the refilling of a magma chamber. The hydrothermal system of Lastarria may be influenced by the uplift, but it's not likely that hydrothermal effects are responsible for the Lazufre deformation. It is not clear whether this deformation is a signal of a future volcanic eruption, but monitoring has been recommended as it may be at risk of a major silicic eruption.
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Most of the water that is discharged by the hot springs appears to be precipitation, which enters the ground east and southeast of El Tatio. The source of heat of the whole complex appears to be the Laguna Colorada caldera, the El Tatio volcanic group or the Cerro Guacha and Pastos Grandes calderas. The movement of the water in the ground is controlled by the permeability of the volcanic material and the Serrania de Tucle–Loma Lucero tectonic block west of El Tatio that acts as an obstacle. As it moves through the ground, it acquires heat and minerals and loses steam through evaporation.
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Left part of Island Park Caldera, with the circular structure of Henry's Fork Caldera in the center of this image The Island Park Caldera, in the U.S. states of Idaho and Wyoming, is one of the world's largest calderas, with approximate dimensions of 80 by 65 km. Its ashfall is the source of the Huckleberry Ridge Tuff that is found from southern California to the Mississippi River near St. Louis. This super-eruption of approximately occurred 2.1 Ma (million years ago) and produced 2,500 times as much ash as the 1980 eruption of Mount St. Helens. Island Park Caldera has the smaller and younger Henry's Fork Caldera nested inside it.
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Finally, they are also common as parasitic and monogenetic cones on complex shield and stratovolcanoes. Globally, cinder cones are the most typical volcanic landform found within continental intraplate volcanic fields and also occur in some subduction zone settings as well. Parícutin, the Mexican cinder cone which was born in a cornfield on February 20, 1943, and Sunset Crater in Northern Arizona in the US Southwest are classic examples of cinder cones, as are ancient volcanic cones found in New Mexico's Petroglyph National Monument. Cone-shaped hills observed in satellite imagery of the calderas and volcanic cones of Ulysses Patera, Ulysses Colles and Hydraotes Chaos are argued to be cinder cones.
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Uturunku is a dormant high volcano in Bolivia with two summit peaks. It consists of a complex of lava domes and lava flows with a total volume of and bears traces of a former glaciation, even though it does not currently carry glaciers. Volcanic activity took place during the Pleistocene and the last eruption was 250,000 years ago; since then Uturuncu has not erupted but active fumaroles occur in the summit region. The volcano rises within the Altiplano- Puna volcanic complex, a larger province of large volcanoes and calderas which over the last few million years have emplaced about in sometimes very large eruptions.
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Volcanic rocks in Pantelleria The island of Pantelleria is located above a drowned continental rift in the Strait of Sicily and has been the focus of intensive volcano-tectonic activity. The 15 kilometre-long () island is the emergent summit of a largely submarine edifice. Two large Pleistocene calderas dominate the island, the older of the two formed about 114,000 years ago and the younger Cinque Denti caldera formed about 45,000 years ago. The eruption that formed the Cinque Denti caldera produced the distinctive green tuff deposit that covers much of the island, and is found across the Mediterranean, as far away as the island of Lesbos in the Aegean.
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Henry's Fork Caldera is the circular structure in the center of this image, with left part of Island Park Caldera The Henry's Fork Caldera in eastern Idaho is a caldera located in an area known as Island Park, west of Yellowstone National Park. The caldera was formed by an eruption 1.3 million years ago of the Yellowstone hotspot, that had a volume of and is the source of the Mesa Falls Tuff. The Henry's Fork Caldera is nested inside of the Island Park Caldera, and the calderas share a rim on the western side. The earlier Island Park Caldera is much larger and more oval and extends well into Yellowstone Park.
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The peaks of the Tushars were formed between 22 and 32 million years ago by volcanic activity that included a calamitous explosion that blew off the top of a massive peak. At the cusp of the Great Basin, the range also shares characteristics of the Colorado Plateau Province to the east. Geologically complex, this area dominated by past volcanism, is composed of lava flows, ash flow tuffs from calderas, volcanic domes, cinder cones, rhyolite, basalt-like rocks, conglomerate, and metals such as gold, molybdenum and uranium. The area contains developed and undeveloped geothermal activity, fluorite, and the hydrothermally-altered rocks of Big Rock Candy Mountain.
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The chronology of volcanic activity at Monowai is largely unknown given the absence of available dating; it is not known, for example, whether the two nested calderas formed during the same eruption. However, the parasitic cones appear to be older than the caldera and the main Monowai cone and most of the volcanic complex probably formed within the last 780,000 years. The formation of the caldera most likely occurred in a nonexplosive fashion and regional tectonic processes may be involved. The caldera formation was probably followed by the formation of the resurgent dome and the cone between the Monowai cone and the caldera, with a trend towards a more explosive activity.
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The volcanism in the area is triggered by the subduction of the Nazca plate beneath the South America plate; magmas formed from the subduction process trigger the melting of the crust. The large calderas are located east of the main volcanic arc of the Central Volcanic Zone, Panizos being east of the main arc. Volcanism in the area is heavily dominated by calderic silicic volcanics with volumes of contrasting to less than andesites. The volcano is part of the so- called Tin belt, a territory in the Andes where large tin mineral deposits are found in granitic and extrusive rocks, formed from sulfidation reactions involving the numerous volcanoes in the area.
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Magmas in the territory are derived from crystal fractionation and were heavily modified by interactions with the crust that reaches a thickness of beneath the Central Volcanic Zone. Research by S. L. de Silva indicates that before 10 mya volcanic activity already existed north of 20°30' in form of the Oxaya and Altos de Pica ignimbrites. Changes in the subduction activity 12-10 mya caused a shortening and thickening of the crust in the central Andes and the formation of melt zones in the deeper crust, associated with the Quechua phase of Andean orogeny. Since 10.6 mya these rose to the surface, forming magma chambers and calderas.
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The andesite inclusions contained in the lava are characteristic for magma mixing processes. The eruption forming the flow may have been caused by the injection of andesite in a pre-existent homogenous dacitic magma chamber. The injection did presumably modify the crystallization processes in the magma chamber and the volatiles in the magma to the point of forcing an eruption. The magmas that gave rise to Cerro Chao may either be the remnants of a previous magma body that gave rise to the neighbouring calderas of the Altiplano-Puna volcanic complex, or may be the sign of a new injection of magmas in the crust.
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The emptied batholith collapsed to form the Questa caldera, which is at least across. The deep erosion of the caldera has made it a useful laboratory for understanding processes occurring below the surface in calderas. For example, fission track dating shows that the upper part of the batholith beneath the caldera had cooled to 100°C by a million years after emplacement and that uplift increased to the south. Bear Canyon Pluton of the Latir volcanic field, east of Questa, New Mexico, USA Magma continued to rise into the volcanic field, forming post-caldera batholiths that intrude both the caldera fill and the nearby pre-caldera volcanic and basement rocks.
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Animation of analogue experiment showing the origin of the volcanic caldera in box filled with flour. Landsat image of Lake Toba, on the island of Sumatra, Indonesia (100 km/62 mi long and 30 km/19 mi wide, one of the world's largest calderas). A resurgent dome formed the island of Samosir. A collapse is triggered by the emptying of the magma chamber beneath the volcano, sometimes as the result of a large explosive volcanic eruption (see Tambora in 1815), but also during effusive eruptions on the flanks of a volcano (see Piton de la Fournaise in 2007) or in a connected fissure system (see Bárðarbunga in 2014–2015).
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Locally, the Wheelwright caldera is also related to the neighbouring Laguna Amarga and Laguna Escondida calderas. The Ermitaño volcano is dated 4.4 - 3.8 million years ago, Peñas Blancas complex formed between 5 and 4.8 million years ago, an unnamed secondary centre 3.9 ± 0.9 million years ago, Pico Wheelwright 5.9 ± 0.9 million years ago, Volcán de Inca 3.3 ± 0.3 million years ago, Volcan Rex erupted 4.9 ± 0.2 million years ago. This stage of volcanic activity was of andesitic to dacitic composition and became more silicic over time. At the closing of this stage, lava domes and associated pyroclastic flows were emplaced within the caldera and across the Cordillera Claudio Gay.
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The volcanic zones are separated by areas where the subducting plate subducts at a flatter angle and volcanism is absent. The Peruvian flat slab between the Northern and the Central Volcanic Zones is associated with the subduction of the Nazca Ridge, the Pampean flat slab between the Central and the Southern Volcanic Zone is associated with the subduction of the Juan Fernandez Ridge, and the Patagonian volcanic gap between the Southern and the Austral Volcanic Zone is associated with the Chile Triple Junction. About 178 volcanoes are found in the Andes, 60 of which have been active in historical times. In addition, large calderas and monogenetic volcanoes exist in the Andes.
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Lacking a well-defined rift zone, the islands have a high rate of inflation prior to eruption. Sierra Negra on Isabela Island experienced a 240 cm uplift between 1992 and 1998, most recent eruption in 2005, while Fernandina on Fernandina Island indicated an uplift of 90 cm, most recent eruption in 2009. Alcedo on Isabela Island had an uplift of greater than 90 cm, most recent eruption in 1993. Additional characteristics of the Galápagos Archipelago are closer volcano spacing, smaller volcano sizes, and larger calderas. For instance, Isabela Island includes 6 major volcanoes, Ecuador, Wolf, Darwin, Alcedo, Sierra Negraa and Cerro Azul, with most recent eruptions ranging from 1813 to 2008.
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The Mount Edziza volcanic complex is a large and potentially active north- south trending complex volcano in Stikine Country, northwestern British Columbia, Canada, located 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. Most of the Mount Edziza volcanic complex is encompassed within a large provincial park called Mount Edziza Provincial Park.
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Armadillo Peak caldera The lava domes, calderas, stratovolcanoes, subglacial mounds and cinder cones forming the volcanic complex were constructed in five phases, each of which began with the effusion of dark olivine basalt which formed the flat-lying shield volcanoes and concluded with the eruption of light-coloured magma. This cyclical behavior is attributed to the episodic rise of basic, mantle-derived alkali basalt both to the surface and partly into crustal reservoirs where the light-coloured magmas with very little aluminum were created by prolonged crystal fractionation. The silica- rich trachyte and comendite lavas are similar to those associated with the most violent eruptions on Earth.
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A 2013 study proposed that a number of craters within Arabia Terra, including Eden Patera, Euphrates Patera, Siloe Patera, and possibly Semeykin crater, Ismenia Patera, Oxus Patera and Oxus Cavus, represent calderas formed by massive explosive volcanic eruptions (supervolcanoes) of Late Noachian to Early Hesperian age. Termed "plains-style caldera complexes", these very low relief volcanic features appear to be older than the large Hesperian-age shield volcanoes of Tharsis or Elysium. Eden Patera, for example, is an irregular, 55 by 85 km depression up to 1.8 km deep, surrounded by ridged basaltic plains. It contains three linked interior depressions, demarcated by arcuate scarps, that have terraces suggestive of lava lake drainage and faults suggestive of collapse.
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In Iceland, volcanic vents, which can be long fissures, often open parallel to the rift zones where the Eurasian and the North American Plate lithospheric plates are diverging, a system which is part of the Mid-Atlantic Ridge. Renewed eruptions generally occur from new parallel fractures offset by a few hundred to thousands of metres from the earlier fissures. This distribution of vents and sometimes voluminous eruptions of fluid basaltic lava usually builds up a thick lava plateau, rather than a single volcanic edifice. But there are also the central volcanoes, composite volcanoes, often with calderas, which have been formed during thousands of years, and eruptions with one or more magma reservoirs underneath controlling their respective fissure system.
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It also allows the incorporation of the low elevation (but prominent) mountains as well as the highest mountains, maximizing territory coverage and ensuring a reasonably even distribution throughout the range. However, it has its drawbacks. For example, an impressive mountain peak dominating a valley may be connected via long high ridges to a barely higher hidden summit. Among the better-known peaks absent from this list are Aiguille du Dru (due to Aiguille Verte), Dent du Géant (Grandes Jorasses), Mont Blanc de Cheilon (Ruinette), Nadelhorn and Täschhorn (Dom), Wetterhorn (Mittelhorn), Piz d'Err (Piz Calderas), Piz Badile (Piz Cengalo), Piz Palü (Piz Zupo), Similaun (Hintere Schwarze), Crozzon di Brenta (Cima Tosa), and Cimon della Pala (Cima Vezzana).
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Over time the overhangs fall into the pit and the crater fills with talus from the collapsing sides and roof. A middle- aged pit crater is cylindrical but its rim will continue to collapse, resulting in the crater's expanding outward until it resembles a funnel or drain—narrower at the bottom than the top. While pit craters and calderas form through similar processes, the former term is usually reserved for smaller features of a mile or less in diameter. The term "pit crater" was coined by C. Wilkes in 1845 to describe craters along Hawaii's East Rift Zone.Wilkes, C., 1845. Narrative of the United States Exploring Expedition during the years 1838, 1839, 1840, 1841, and 1842, Vol. 4.
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DR-2 enters the town of Baní, the capital and largest city of Peravia and divides into two local one-way main streets that cross the city center. This has been a problem still unresolved which causes great traffic congestion along these two main street and forces travelers going farther west to enter the city of Bani without an option to bypass it. A bypass of Bani to the north or south of the town would allow the motorist to save time when going to western cities. DR-501 serves as a spur route of DR-2 in the center of Bani serving the small villages of Villa Sombrero, Matanzas, and Las Calderas.
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Kulshan Caldera's intracaldera ignimbrite deposit near Upper Swift Creek The Kulshan Caldera is a Pleistocene volcano in the North Cascades of Washington and one of the few true calderas identified in the entire Cascade Range. Formation of the caldera about 1.5 million years ago was accompanied by the largest eruption in the history of the Mount Baker volcanic field when ice covered much of the region around Mount Baker. More than of rhyodacite magma exploded from a shallow magma chamber and filled the caldera and surrounding valleys with ignimbrite. Subsequent glacial erosion removed most of the tephra fallout near the source of the eruption, leaving behind a thick tephra deposit preserved south of the caldera.
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The close distance of the encounter allowed Voyager to acquire images of the sub-Jovian and south polar regions of Io with a best resolution of less than per pixel. Unfortunately, many of the close-up images were limited by smear as the result of problems with Voyager's internal clock due to the high radiation environment, causing some narrow-angle-camera exposures of Io to be acquired while the Voyagers scan platform was moving between targets. The highest-resolution images showed a relatively young surface punctuated by oddly shaped pits that appeared more akin to volcanic calderas than to impact craters, mountains taller than Mount Everest, and features resembling volcanic lava flows.
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Islands of fire , Cosmos Magazine. These include eruptions from Macauley Island and the Taupo, Whakamaru, Mangakino, Reporoa, Rotorua, and Haroharo calderas. Two relatively recent eruptions from the Taupo volcano are perhaps the best known. Its Oruanui eruption was the world's largest known eruption in the past 70,000 years, with a Volcanic Explosivity Index (VEI) of 8. It occurred around 26,500 years ago and deposited approximately 1,200 km³ of material. Tephra from the eruption covered much of the central North Island with ignimbrite up to 200 metres (650 feet) deep, and most of New Zealand was affected by ash fall, with even an 18 cm (7 inch) ash layer left on the Chatham Islands, away.
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More conventionally, springs, caves, shores, rivers, volcanic calderas—'a huge crater of an extinct volcano...[as] another symbol of transcendence'Joseph Henderson, in Jung 1978, 152.—fords, passes, crossroads, bridges, and marshes are all liminal: '"edges", borders or faultlines between the legitimate and the illegitimate'.Richard Brown in Corcoran 2002, 196 Oedipus (an adoptee and therefore liminal) met his father at the crossroads and killed him; the bluesman Robert Johnson met the devil at the crossroads, where he is said to have sold his soul. Major transformations occur at crossroads and other liminal places, at least partly because liminality—being so unstable—can pave the way for access to esoteric knowledge or understanding of both sides.
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Extinct calderas up to 35 miles wide are preserved in the mountains of south-central Nevada, particularly near the Tonopah range, as well as in the Hot Creek, Monitor, Reveille and Kawich ranges. Welded ignimbrite formed as hot ash formed natural glass on rock surfaces. Violent volcanism continued in the southwest until seven million years ago, forming the ancestral Cascade arc, named for its similarity to the Cascade Range in the Pacific Northwest. Additionally, the Walker Lane—an area of northwest trending right-lateral strike-slip faults formed 12 million years ago—associated with some of the most intense eruptions, such as the 16 to 6.5 million year old Southwest Nevada volcanic field.
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Barinas has a contrast between landscapes of mountains, plains, rivers and streams, offering tourists a variety of options, from contemplating rare species in their habitat, to enjoying its spectacular parks and natural spas. From the city of Barinas to the state of Merida, passing through the municipality of Bolivar, which includes the towns of Barinitas, Altamira de Caceres and Calderas, with a pleasant climate, characteristic of the tropical rainforest. Barinitas, the capital of the municipality, has places for tourism: the Moromoy Park for camping; the Balneario La Barinesa, which has recreational facilities; and, towards the southeast, the El Cacao Sector, for mountain biking practice. There is also the boulevard of Plaza Bolívar and the San Pedro Church.
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Vilama is a Miocene caldera in Bolivia and Argentina. Straddling the border between the two countries, it is part of the Central Volcanic Zone, one of the four volcanic belts in the Andes. Vilama is remote and forms part of the Altiplano-Puna volcanic complex, a province of large calderas and associated ignimbrites that were active since about 8 million years ago, sometimes in the form of supervolcanoes. The Vilama caldera was originally estimated to have a size of but the size was later revised to be between and and is almost entirely buried beneath younger volcanoes that have grown along the margin of the caldera; volcanic activity on these volcanoes continued into the Pleistocene.
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Instead, tidal-generated heat is a better hypothesis as Io is under great tidal influence imposed by Jupiter and other large moons of Jupiter, similar to the Earth and the Moon. The first observation supporting this was the active volcanism found on Io. There are over 100 calderas with abundant and widely spread radiating lava flows. And the composition of the lava is interpreted to be mainly sulfur and silicates from the high eruption temperature of at least 1200 K. In addition to extensive volcanism, mountain ranges are the second observation on Io's surface. Io has 100~150 mountains with mean height of 6 km and a maximum height of 17 km.
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As a by-product of this activity, sulfur, sulfur dioxide gas and silicate pyroclastic material (like ash) are blown up to into space, producing large, umbrella-shaped plumes, painting the surrounding terrain in red, black, and white, and providing material for Io's patchy atmosphere and Jupiter's extensive magnetosphere. Io's surface is dotted with volcanic depressions known as paterae which generally have flat floors bounded by steep walls. These features resemble terrestrial calderas, but it is unknown if they are produced through collapse over an emptied lava chamber like their terrestrial cousins. One hypothesis suggests that these features are produced through the exhumation of volcanic sills, and the overlying material is either blasted out or integrated into the sill.
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Around the same time, about 614,000 years ago, an explosive eruption southwest of Lassen Peak produced of pumice and ash, covering the area between the vent and what is now the city of Ventura, California. This deposit, referred to as the Rockland tephra, reaches up to several inches in thickness within the San Francisco Bay area, and can be found as far as northern Nevada and southern Idaho. The same eruption also formed one of three known calderas within the Cascade, the others being Crater Lake and the Kulshan Caldera at Mount Baker. Shortly after, the Lassen volcanic center, a cluster of closely spaced volcanoes, formed in the area, covering the nearby caldera.
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The shield-stage lavas that built the enormous main mass of the mountain are tholeiitic basalts, like those of Mauna Kea, created through the mixing of primary magma and subducted oceanic crust. Mauna Loa's summit hosts three overlapping pit craters arranged northeast-southwest, the first and last roughly in diameter and the second an oblong feature; together these three craters make up the summit caldera Mokuʻāweoweo, so named for the Hawaiian ʻāweoweo fish (Priacanthus meeki), purportedly due to the resemblance of its eruptive fires to the coloration of the fish. Mokuʻāweoweo's caldera floor lies between beneath its rim and it is only the latest of several calderas that have formed and reformed over the volcano's life.
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The African large low-shear-velocity province (superplume) The mantle plume hypothesis proposes that areas of volcanism not readily explained by plate tectonics, called hotspots, are a result of thermal upwelling from as deep as the core- mantle boundary that become diapirs in the crust. This is an actively contested theory, although tomographic images suggest there are anomalies beneath some hotspots. The best imaged of these are large low-shear-velocity provinces, or superplumes, visible on S-wave models of the lower mantle and believed to reflect both thermal and compositional differences. The Yellowstone hotspot is responsible for volcanism at the Yellowstone Caldera and a series of extinct calderas along the Snake River Plain.
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Area of the Cascadia subduction zone, with the Mount Meager massif being the northernmost red triangle in the Cascade Volcanic Arc The Mount Meager massif is part of the Garibaldi Volcanic Belt (GVB), the northernmost segment of the . This volcanic belt includes cinder cones, calderas, stratovolcanoes and subglacial volcanoes (volcanoes under glaciers or ice sheets) that have been active in the last 10,000 years. The latest explosive eruption in the Garibaldi Volcanic Belt occurred at a crater on the northeastern slope of the massif about 2,400 years ago, which forms a clearly defined depression. The GVB extends north from the Watts Point volcano to at least as far as the Meager massif.
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Farther north in the large Ha-Iltzuk and Waddington icefields, it includes two large dissected calderas called Silverthrone Caldera and Franklin Glacier Complex while the Queen Charlotte Islands to the northeast contain a volcanic formation ranging in age from Miocene to Pliocene called the Masset Formation. Although widely separated from each other, all Pemberton Belt rocks are of similar age and have similar magma compositions. Therefore, these magmatic rocks are believed to be products of arc volcanism related to subduction of the Farallon Plate. By late Pliocene time the Farallon Plate had been greatly reduced in size and its northern portion ultimately broke off between five and seven million years ago to form a new plate boundary called the Nootka Fault.
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Geologically, southwestern Utah is at the margin between the geologic provinces known as the Colorado Plateau and the Basin and Range Province, the former of which features flat lying sediments while the latter is characterized by steep horsts and grabens. After the Oligocene and Miocene, during which volcanism was characterized by calderas and stratovolcanoes, beginning 8 million years ago smaller volumes of mostly mafic magma formed lava domes, shield volcanoes, volcanic cones and volcanic plugs. The Markagunt Plateau is part of the High Plateaus geologic province, in the Colorado Plateau and at its margins with the Basin and Range Province. It is a wide fault-bounded block and the basement underneath the volcanoes is formed by various Cretaceous to Miocene sedimentary or volcanic rocks.
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The earliest eruptions of the volcano occurred around one million years ago, explosive activity producing ignimbrite. The explosive eruption phase finished around 830,000 years before present, when the nature of the activity changed to a mix of pyroclastic and effusive, lava eruptions which built up the mountain and which have been dated to around 500,000 years ago. One of the explanations advanced for the Valle dei Grigi is that it is the result of the collapse of a sector of the mountain, as occurred during the 1980 eruption of Mount St. Helens and the 1792 eruption of Mount Unzen. The most recent phase involved further lava flows and the growth of lava domes in the Valle dei Grigi, including the formation of two calderas.
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During Galileo's encounters with Io between October 1999 and October 2001, the spacecraft observed Pele on three occasions using its camera and infrared spectrometers while the volcano was on Io's night-side. The cameras revealed a curved line of bright spots along the margin of the Pele patera (a term used for volcanic depressions on Io, akin to calderas). Within the east-west dark band along the southeastern portion of the patera, a large amount of thermal emission was observed, with temperatures and distribution consistent with a large, basaltic lava lake. Thermal emission at Pele was also seen in December 2000 by the Cassini spacecraft, in December 2001 from the Keck Telescope in Hawaii, and by the New Horizons spacecraft in February 2007.
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Cerro Guacha, La Pacana and Pastos Grandes are calderas within this province which covers a surface of , with geothermal manifestations in El Tatio and Sol de Manana being the latest manifestations of volcanism in the area. A group of lava domes with a diameter of of dacitic composition forms the centre of the complex, with the domes having formed either during one single eruption or several. These domes form a ring structure with thin lava cover in its centre, which may be the rim of a collapse caldera formed in the later stages of the main Panizos eruption and filled by later eruption stages, as suggested by the outward dip of the lower unit of the Panizos Ignimbrite. This caldera has a diameter of .
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Volcanic rocks from the field have basaltic compositions. Devil Mountain Maar Devil Mountain Maar is wide and deep, while North Killeak Maar, South Killeak Maar and Whitefish Maar are , and wide and the Killeak Maars reach depths of over ; Whitefish Maar is much shallower with a depth of . Such dimensions make the Espenberg maars the largest on Earth and the Espenberg maars comparable in size with calderas; other maars at lower latitudes are much smaller. The maars are mostly circular with the exception of Devil Mountain Maar which is partly separated by a small sand spit into the northern wide North Devil Mountain Maar and the wide South Devil Mountain Maar; formerly they were considered to be two separate maars.
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The volcano has a caldera at its summit, which has a diameter of and features two crater lakes: Paulina Lake and East Lake. This caldera, known as the Newberry Crater, is forested, with small parts of its surface covered with lava flows and pumice deposits. Before the caldera's creation, the mountain's summit was greater in height than its current elevation. The caldera has reformed several times throughout the volcano's history, burying the caldera floor to a depth of and creating concentric calderas, each smaller than its predecessor. The first caldera—the volcano's largest caldera, forming approximately 300,000 years ago—was produced by the eruption of of pyroclastic ejecta, which created the Tepee Draw tuff and ash deposits that cover the volcano's eastern flank.
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Being in the intertropical zone and extending more towards the meridians than the parallels, Barinas has a climate determined by altitude, winds and two seasons: the dry season, from October to March, and the rainy season, from April to September. Of these factors, the altitude modifies the temperatures more forcefully. The cold winds that flow from the east of the Mérida mountain range to the Llanos Altos cause the characteristic phenomenon of the Barinese wind. According to Köppen's classification, the Sierra del Tapo-Caparo and the Llanos have a savanna climate (Aw); the Piedemonte and Alto Apure, a monsoon climate (Am); the Sierra Nevada and Sierra de Calderas, a humid mountain climate (Cfbi); and the highest parts of the last two mountain ranges, a tropical alpine climate (ETH).
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The latter form the so-called Altiplano-Puna volcanic complex centered around the Chile-Bolivia-Argentina tripoint, which was mainly active in the Miocene to Pleistocene and is one of the largest such ignimbrite provinces in the world. These centres mainly erupted dacitic magmas. Among the Altiplano-Puna volcanic complex volcanoes are the Cerro Panizos northeast of Vilama and the Cerro Guacha southwest of Vilama; the Vilama, Coruto and Guacha calderas have been designed the "Eduardo Avaroa caldera complex" (). The volcanic history of the Altiplano-Puna volcanic complex is poorly known, due to the overlap and burial of older volcanic centres beneath younger ones, difficulties in separating different ignimbrites, the lack of erosion resulting in poor exposure of the units and the challenges of accessing the remote region.
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Together with the neighbouring Laguna Amarga caldera and Laguna Escondida caldera Wheelwright forms an alignment of Miocene-Pliocene calderas; the latter caldera in part overlaps with the Wheelwright caldera. The region coincides with a lineament of volcanoes which forms the southern margin of the volcanically active Central Andes; south of this margin the Nazca Plate subducts beneath the South America Plate at a shallow angle and Quaternary volcanism is absent. The oldest outcrops are found in the Cordillera Claudio Gay mountain range just west of Wheelwright; these outcrops are Paleozoic sediments and volcanic rocks. Volcanic arc volcanism has been ongoing in the region since 180 million years ago and migrated eastward during that time, but the modern arc developed 26 million years ago when the Farallon Plate broke up.
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On the other end of the chain, the seamounts become short ridges decorated by volcanic cones; the Pacific-Antarctic Ridge is migrating northwestward and approaching the hotspot, and the younger crust close to the ridge results in the morphology of developing volcanoes being altered. The Foundation chain eventually becomes a set of three ridges close to the Pacific-Antarctic Ridge, the northern two of which are the more voluminous ones. These northern ridges are probably the main ones; the southern one may have formed through cracks in the crust induced by the northern ridge, but it might also be a "paired" expression of a hotspot similar to the Kea and Loa trends in Hawaii. The seamounts reach depths of beneath sea level (the highest seamount is located at ), and contain typical volcanic features such as smaller volcanic cones, calderas and individual rift zones.
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The strata, which vary in age from 39 million years to 18 million years, were formed mainly from ashfalls from volcanoes due to a series of calderas now linked to the Yellowstone hotspot. Some of the major layers within the group exposed in the Picture Gorge district are the Big Basin Formation and Bridge Creek Beds (35 to 32 million years), the Turtle Cove Formation (30 to 28 million years), the Picture Gorge Ignimbrite (28.7 million years), the Kimberly Formation (28 to 25 million years), and the Haystack Formation (25 to 18 million years). Located in the general vicinity of what became the Cascade Range, the John Day volcanoes emitted large volumes of ash and dust, much of which settled in the John Day basin. The rapid deposition of the ash preserved the remains of plants and animals living in the region.
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The conquest of the county by Aragonese Christians was in the 10th century, although the name of “Fonte Calderas” (“Hot Source”) does not appear until 1137 in a donation by the Aragonese king Ramiro II "The Monk". As a result of the conquest a defense tower was built in the place called the “Pacatorre”, to whose protection began to form Fuencalderas. Nonetheless, the origin of Fuencalderas would have relationship with the town of Liso (according to some sources "Eliso") that was situated to 10 km to the north of Fuencalderas. Liso could have Roman origin and whose first mention documentary dated already of the year 938. From the 10th to 12th centuries Liso was an important part of the defensive line of the Kingdom of Aragon in the region, reaching the range “Burgh of Liso”, while that Fuencalderas was of little entity.
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It is believed that Alcedo volcano emerged from the sea approximately 313,000 years ago, based on its sub -aerial volume of 234 km3 and average eruption rate of 1x106 m3 per year. This has produced a volcano that is 1130m high with a caldera that measures 6.1 x 7.4 km. Alcedo volcano is similar to its neighbours to the north, Darwin and to the south, Sierra Negra which also have shallow slopes for the majority of their height. It is also similar to these two in that the depth of the caldera is less than 25% of the height of the volcano. This contrasts with the other major shield volcanoes, Cerro Azul, Wolf on Isabela and Fernandina that have much steeper slopes and have calderas that have a depth which is 40-60% of the sub-aerial height.
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Glass Mountain, a large obsidian flow at Medicine Lake Volcano in California Obsidian is found in locations which have undergone rhyolitic eruptions. It can be found in Argentina, Armenia, Azerbaijan, Australia, Canada, Chile, Georgia, El Salvador, Greece, Guatemala, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, Papua New Guinea, Peru, Scotland, The Canary Islands, Turkey and the United States. Obsidian flows which may be hiked on are found within the calderas of Newberry Volcano and Medicine Lake Volcano in the Cascade Range of western North America, and at Inyo Craters east of the Sierra Nevada in California. Yellowstone National Park has a mountainside containing obsidian located between Mammoth Hot Springs and the Norris Geyser Basin, and deposits can be found in many other western U.S. states including Arizona, Colorado, New Mexico, Texas, Utah, and Washington,Washington Obsidian Source Map . Obsidianlab.com.
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Progression of ages of rhyolitic (silicic) lavas and calderas from alt=The diagram displays the movement of the North American tectonic plate with an arrow moving from right to left, with ovular shapes indicating the age progression of centers of rhyolitic (silicic) lavas. From right to left, three major volcanic centers are indicated with concentric circles, Yellowstone Caldera to McDermitt Caldera to Newberry Caldera Overlapping with the northwestern corner of the Basin and Range Province, also known as the High Lava Plains, Newberry Volcano lies within a Cenozoic highland marked by normal faults known as the Brothers Fault Zone. It is situated at the intersection of the Brothers Fault Zone with the north–northwest-trending Sisters and northeast-trending Walker Rim fault zones. In the mantle under Newberry Volcano, P and S seismic waves exhibit an unusually low wave velocity.
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The archipelago of the Azores includes a rich and vast geodiversity, and an important geological heritage, comprising various locales of interest to the scientific and learning communities, in addition to its socio-economic importance to tourism. Due to it being an archipelago, the Azores Geopark is disperse: guaranteeing a representative geodiversity that characterizes the Azorean territory; manifesting in a history based on geological and active volcanism; with conservation strategies that are common; and based on a decentralized management structure with supports in all islands. Characteristic of the Azorean geological history is a range of diverse features that includes (but is not limited to) volcanoes, calderas, lakes, lava fields, fumaroles, hot springs and thermal waters, volcanic caves, fajãs, fault scarps and marine fossil deposits. Beyond this heritage, there are other values of reference in the archipelago, such as its rich biodiversity, architecture, culture and ethnography.
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Many rivers descend from its snowy peaks and lagoons; the Ariguani, Ariguanicito, Badillo, Calderas, Cesar, Curiba, Donachui, Garupal, Guatapuri, which borders the city of Valledupar; and the Mariangola. The Municipality of Valledupar is bordered on the north with the municipalities of Riohacha and San Juan del Cesar in the department of La Guajira. To the south are the municipalities of El Paso and Los Robles La Paz in the department of Cesar; to the east are the municipalities of Villanueva and Urumita, also in the Department of La Guajira; and to the west are the municipalities Fundacion and Aracataca, in the department of Magdalena. The municipality has an area of about 4,977.96 km², from which 72,660 km² pertain to the Arhuacos Indian Reserve, 399.52 km² to the Kogui and Wiwa Indian Reserve, and 425.60 km² to the Sierra Nevada de Santa Marta National Park.
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Volcanic activity has also been promoted as a possible cause of the cat gap as well as other extinctions during this time period. The La Garita Caldera is a large volcanic caldera located in the San Juan Mountains in southwestern Colorado, United States, and is one of a number of calderas that formed during a massive ignimbrite flare-up in Colorado, Utah, and Nevada during the Oligocene Epoch. The La Garita Caldera was the site of the Fish Canyon eruption, an enormous eruption about 27 million years ago. The scale of the Fish Canyon eruption was far beyond anything known in human history (erupting more than for a VEI 8+ magnitude), and was possibly the most energetic event on Earth since the Chicxulub impact, which is thought by many paleontologists to have caused the extinction of the dinosaurs in the Cretaceous–Paleogene extinction event.
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Historical eruptions at Raoul during the 19th and 20th centuries have sometimes occurred simultaneously from both calderas, and have consisted of small-to-moderate phreatic eruptions, some of which formed ephemeral islands in Denham caldera. A high unnamed submarine cone, one of several located along a fissure on the lower NNE flank of Raoul volcano, has also erupted during historical time, and satellitic vents at Raoul are concentrated along two parallel NNE-trending lineaments. The Denham caldera was named for the nearby Denham Bay, itself named by Royal Navy Captain Henry Mangles Denham in HMS Herald, who came to complete a (chart) survey of the island on 2 July 1854. His son Fleetwood James Denham (16yrs) died from a tropical fever, and was buried near the beach at the head of Denham Bay, where a number of the grass-grown graves of former settlers were.
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The Mogollon-Datil volcanic field is a large silicic volcanic field in western New Mexico (Mogollon Mountains-Datil, New Mexico). It is a part of an extensive Eocene to Oligocene volcanic event which includes the San Juan volcanic field in southwestern Colorado, the Trans-Pecos volcanic field in west Texas and north central Mexico, the Boot Heel volcanic field in the bootheel of southwestern New Mexico and adjacent areas of Arizona and Mexico; and the vast volcanic field of the Sierra Madre Occidental of western Mexico. The Mogollon-Datil volcanic field was formed in "four discrete pulses representing synchronized activity of two separate cauldron complexes". Calderas of Mogollon-Datil volcanic field The Socorro, New Mexico region (Socorro-Magdalena caldera cluster) of the central Rio Grande rift hosts an inflating mid-crustal sill-like magma body at a depth of 19 km that is responsible for anomalously high earthquake activity in the vicinity.
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They also did not find it feasible to assume that the layered deposits were consistent with the materials comprising their valley walls, but did note that some canyon wall landslide material would inevitably become incorporated into these layered deposits in the case of a depositional origin. Notably, Nedell and co-workers could not firmly support or oppose a volcanic origin for the deposits, identifying no calderas associated with any of the layered deposits, including Ganges Mensa. However, they noted that the presence of some central structure—either volcanic and/or relict—could account for the large sizes of these layered deposits relative to the amount of debris one might typically expect to deposit in a lacustrine environment. Goro Komatsu and Robert G. Strom of the University of Arizona submitted an abstract to the 21st Lunar and Planetary Science Conference in 1990 to discuss recent observations about the geology of layered terrains on the mesa with possible volcanic intrusions.
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The volcanism of Canada is represented by many types of landform including lava flows, volcanic plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcanoes, calderas, diatremes, and maars, along with examples of more less common volcanic forms such as tuyas and subglacial mounds. It has a very complex volcanic history spanning from the Precambrian eon at least 3.11 billion years ago when this part of the North American continent began to form. Although the country's volcanic activity dates back to the Precambrian eon, volcanism continues to occur in Western and Northern Canada where it forms part of an encircling chain of volcanoes and frequent earthquakes around the Pacific Ocean called the Pacific Ring of Fire. But because volcanoes in Western and Northern Canada are in remote rugged areas and the level of volcanic activity is less frequent than with other volcanoes around the Pacific Ocean, Canada is commonly thought to occupy a gap in the Pacific Ring of Fire between the volcanoes of western United States to the south and the Aleutian volcanoes of Alaska to the north.
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Older volcanic activity occurred in the field during the Oligocene and Miocene, generating calderas (usually large craters formed by the explosion or collapse of a volcano) such as the Central Nevada Caldera Complex and the Lunar Lake caldera which underlies much of the northern Lunar Crater volcanic field. The volcanism produced ignimbrites, andesitic lavas and tuffs such as the 24 million years old Buckwheat Rim Tuff that Lunar Crater is embedded in; some of these volcanic rocks form structural blocks such as the Citadel Mountain block and the Pancake Range and others are correlated to ignimbrite sheets elsewhere in Nevada. An early caldera-forming ignimbritic phase was followed by an andesitic lavic phase, and in the last 11 million years basaltic eruptions have taken place in the Basin and Range. These older volcanics also form the basement (underground rock surface) in the area, while parts of the region are covered by alluvium (sediment that was transported by water); sometimes the older volcanics are buried beneath this alluvium and playa deposits.
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This includes mountains and calderas like Mount Shasta and Lassen Peak in California, Crater Lake, Three Sisters, and Mount Hood in Oregon, Mount Saint Helens, Mount Adams, Glacier Peak, and Mount Baker in Washington, and Mount Cayley, Mount Garibaldi, Silverthrone Caldera, and Mount Meager in British Columbia. All of the above are dormant, but could return to activity, and scientists on both sides of the border gather research of the past eruptions of each in order to predict how mountains in this arc will behave and what they are capable of in the future, including Mount Rainier. Of these, only two have erupted since the beginning of the twentieth century: Lassen in 1915 and St. Helens in 1980 and 2004. However, past eruptions in this volcanic arc have multiple examples of sub-plinian eruptions or higher: Crater Lake's last eruption as Mount Mazama was large enough to cause its cone to collapse, and Mt. Rainier's closest neighbor, Mount St. Helens, produced the largest eruption in the continental United States when it erupted in 1980.
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Volcanic rock-formations at Playa de Mónsul, possibly the most popular beach Las Salinas de Cabo de Gata The pueblo of San José Playa de los Genoveses is the second most popular beach and within walking distance of the pueblo of San José Semana Santa in Níjar- although processions may look sinister, they are quite moving and far removed from practices often associated with such clothing; note the ceramics for which Níjar is known Playa el Playazo One of the more popular beaches near to the pueblo of Rodalquilar Playa de San Miguel The church shown here has a curious history and the old abandoned fishing boats are left as a type of "living museum" Cabo de Gata-Níjar Natural Park is characterised by volcanic rock formations - lava flows, volcanic domes, volcanic calderas. The park joined UNESCO's Global Geoparks Network in 2006, and is also a member of the European Geoparks Network. European geoparks website Between the village of San Miguel and the Cabo de Gata point are salt flats (Las Salinas de Cabo de Gata) separated from the sea by a sand bar. The salt flats are a Ramsar site.
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