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Subglacial Mound
A subglacial mound (SUGM) is a type of subglacial volcano. This type of volcano forms when lava erupts beneath a thick glacier or ice sheet. The magma forming these volcanoes was not hot enough to melt a vertical pipe right through the overlying glacial ice, instead forming hyaloclastite and pillow lava deep beneath the glacial ice field. Once the glaciers had retreated, the subglacial volcano would be revealed, with a unique shape as a result of their confinement within glacial ice. They are somewhat rare worldwide, being confined to regions which were formerly covered by continental ice sheets and also had active volcanism during the same period. They are found throughout Iceland, Antarctica and the Canadian province of British Columbia. Subglacial mounds can be mistaken for cinder cones because they may have a similar shape. An example of this confusion is Pyramid Mountain in the Wells Gray-Clearwater volcanic field The Wells Gray-Clearwater volcanic field, also called the C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramid Mountain
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Pyramid Mountain can refer to: ;Antarctica * Pyramid Mountain (Antarctica), in the Quartermain Mountains ;Canada * Pyramid Mountain (Alberta) in Jasper National Park, Alberta * Pyramid Mountain (Garibaldi Provincial Park) in Garibaldi Provincial Park, British Columbia * Pyramid Mountain (Wells Gray-Clearwater) in Wells Gray-Clearwater Volcanic Field of British Columbia ;United States: * Pyramid Mountain (Kodiak Island), Alaska *Pyramid Mountains, New Mexico * Pyramid Mountain (Clallam County, Washington) in Olympic National Park * Pyramid Mountain (Montana), in the Beartooth Mountains See also * Pyramid Peak (other) Pyramid Peak may refer to several places: United States *Pyramid Peak (Alaska) *Pyramid Peak (California) (3,043 m) *Pyramid Peak (Fresno County, California) (3,895 m) *Pyramid Peak (Inyo County, California) (2,044 m) *Pyramid Peak (Colorado) (4, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegeta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subglacial Mounds
Subglacial means "formed, or occurring beneath a glacier or other body of ice". It may refer to: * Subglacial eruption * Subglacial lake * Subglacial stream * Subglacial volcano A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava. Today they are most ... {{Disambiguation Glaciology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wells Gray-Clearwater Volcanic Field
The Wells Gray-Clearwater volcanic field, also called the Clearwater Cone Group, is a potentially active monogenetic volcanic field in east-central British Columbia, Canada, located approximately north of Kamloops. It is situated in the Cariboo Mountains of the Columbia Mountains and on the Quesnel and Shuswap Highlands. As a monogenetic volcanic field, it is a place with numerous small basaltic volcanoes and extensive lava flows. Most of the Wells Gray-Clearwater volcanic field is encompassed within a large wilderness park called Wells Gray Provincial Park. This park was established in 1939 to protect Helmcken Falls and the unique features of the Clearwater River drainage basin, including this volcanic field. Five roads enter the park and provide views of some of the field's volcanic features. Short hikes lead to several other volcanic features, but some areas are accessible only by aircraft. Geology Pleistocene epoch Based on radiocarbon and potassium-argon dating, vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramid Mountain (Wells Gray-Clearwater)
Pyramid Mountain is a subglacial mound located on the Murtle Plateau in Wells Gray Provincial Park, east-central British Columbia, Canada. Formation Pyramid Mountain erupted about 12,000 years ago. It was once mistaken for a cinder cone and is now known to have erupted underneath about of glacial ice. The volcano erupted vigorously and cooled rapidly when the hot lava contacted the surrounding ice and melted it, creating an envelope of water around the rising volcano. The result was a cement-like surface with smoothed cobbles of granite, schist, phyllite and other non-volcanic pebbles which were carried by the ice from many kilometers distant. As a result of this type of eruption, Pyramid Mountain has no crater and no lava flows stretching away from its base. The secondary cone to the east (best seen from Clearwater Valley Road near Hemp Creek) was not formed by a separate eruption, but was simply a slump when the ice melted away from Pyramid, releasing the pressure against its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinder Cone
A cinder cone (or scoria cone) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is symmetrical; with slopes between 30 and 40°; and a nearly circular ground plan. Most cinder cones have a bowl-shaped crater at the summit. Mechanics of eruption Cinder cones range in size from tens to hundreds of meters tall and often have a bowl-shaped crater at the summit. They are composed of loose pyroclastic material ( cinder or scoria), which distinguishes them from ''spatter cones'', which are composed of agglomerated volcanic bombs. The pyroclastic material making up a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, forests, lakes, mountains, inland deserts and grassy plains, and borders the province of Alberta to the east and the Yukon and Northwest Territories to the north. With an estimated population of 5.3million as of 2022, it is Canada's third-most populous province. The capital of British Columbia is Victoria and its largest city is Vancouver. Vancouver is the third-largest metropolitan area in Canada; the 2021 census recorded 2.6million people in Metro Vancouver. The first known human inhabitants of the area settled in British Columbia at least 10,000 years ago. Such groups include the Coast Salish, Tsilhqotʼin, and Haida peoples, among many others. One of the earliest British settlements in the area was Fort Victoria, established in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its surrounding areas) is home to over 65% of the population. Iceland is the biggest part of the Mid-Atlantic Ridge that rises above sea level, and its central volcanic plateau is erupting almost constantly. The interior consists of a plateau characterised by sand and lava fields, mountains, and glaciers, and many glacial rivers flow to the sea through the lowlands. Iceland is warmed by the Gulf Stream and has a temperate climate, despite a high latitude just outside the Arctic Circle. Its high latitude and marine influence keep summers chilly, and most of its islands have a polar climate. According to the ancient manuscript , the settlement of Iceland began in 874 AD when the Norwegian chieftain Ingólfr Arnarson became the fir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subglacial Volcano
A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava. Today they are most common in Iceland and Antarctica; older formations of this type are found also in British Columbia and Yukon Territory, Canada. During the eruption, the heat of the lava from the subglacial volcano melts the overlying ice. The water quickly cools the lava, resulting in pillow lava shapes similar to those of underwater volcanoes. When the pillow lavas break off and roll down the volcano slopes, pillow breccia, tuff breccia, and hyaloclastite form. The meltwater may be released from below the ice as happened in Iceland in 1996 when the Grímsvötn caldera erupted, melting 3 km3 of ice and giving rise to a large glacial lake outburst flood. The shape of subglacial volcanoes tends to be quite characteristic and unusual, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Survey Of Canada
The Geological Survey of Canada (GSC; french: Commission géologique du Canada (CGC)) is a Canadian federal government agency responsible for performing geological surveys of the country, developing Canada's natural resources and protecting the environment. A branch of the Earth Sciences Sector of Natural Resources Canada, the GSC is the country's oldest scientific agency and was one of its first government organizations. History In September 1841, the Province of Canada legislature passed a resolution that authorized the sum of £1,500 sterling be granted to the government for the estimated expense of performing a geological survey of the province. In 1842, the Geological Survey of Canada was formed to fulfill this request.Christy Vodden (1992)No Stone Unturned: The First 150 years of the Geological Survey of Canada Geological Survey of Canada Web site William Edmond Logan was in Montreal at the time and made it known that he was interested in participating in this survey. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pillow Lava
Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava underwater, or ''subaqueous extrusion''. Pillow lavas in volcanic rock are characterized by thick sequences of discontinuous pillow-shaped masses, commonly up to one meter in diameter. They form the upper part of Layer 2 of normal oceanic crust. Composition Pillow lavas are commonly of basaltic composition, although pillows formed of komatiite, picrite, boninite, basaltic andesite, andesite, dacite or even rhyolite are known. In general, the more felsic the composition (richer in silica - resulting in an Intermediate composition), the larger the pillows, due to the increase in viscosity of the erupting lava. Occurrence They occur wherever lava is extruded underwater, such as along marine hotspot volcano chains and the constructive plate boundaries of mid-ocean ridges. As new oceanic crust is formed, thick sequences of pillow lavas are erupted at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
