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Mount Denison
Mount Denison is a stratovolcano and one of the highest peaks on the Alaska Peninsula. Discovered in 1923 by Harvard professor Kirtley Fletcher Mather, the mountain was named for the geologist's alma mater, Denison University. The mountain's connection to Denison also include its first climbers: all members of the first two ascent teams as well as the group that attempted in 1977 were either students, alumni, or faculty of the university. Mount Denison is located at the end of a volcanic chain in a heavily glaciated and very remote section of Katmai National Park. It is possibly the tallest mountain in the national park, though some sources list Mount Griggs as the highest. Mount Griggs, on the other hand, is much more accessible, being next to the Valley of Ten Thousand Smokes, which can be reached via the road from the national park's visitor center. There is no record of an eruption, but Mount Denison was probably active some time in the last 10,000 years (the Holocene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Peaks Of Alaska
This article comprises three sortable tables of major mountain peaksThis article defines a significant summit as a summit with at least of topographic prominence, and a major summit as a susexxleast of topographic prominence. All summits in this article have at least 500 meters of topographic prominence. An ultra-prominent summit is a summit with at least of topographic prominence. of the U.S. State of Alaska. The summit of a mountain or hill may be measured in three principal ways: #The topographic elevation of a summit measures the height of the summit above a geodetic sea level.If the elevation or prominence of a summit is calculated as a range of values, the arithmetic mean is shown. The first table below ranks the 100 highest major summits of Alaska by elevation. #The topographic prominence of a summit is a measure of how high the summit rises above its surroundings.The topographic prominence of a summit is the topographic elevation difference between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katmai National Park
Katmai National Park and Preserve is an American national park and preserve in southwest Alaska, notable for the Valley of Ten Thousand Smokes and for its brown bears. The park and preserve encompass , which is between the sizes of Connecticut and New Jersey. Most of the national park is a designated wilderness area. The park is named after Mount Katmai, its centerpiece stratovolcano. The park is located on the Alaska Peninsula, across from Kodiak Island, with headquarters in nearby King Salmon, about southwest of Anchorage. The area was first designated a national monument in 1918 to protect the area around the major 1912 volcanic eruption of Novarupta, which formed the Valley of Ten Thousand Smokes, a , pyroclastic flow. The park includes as many as 18 individual volcanoes, seven of which have been active since 1900. Initially designated because of its volcanic history, the monument was left undeveloped and largely unvisited until the 1950s. The monument and surrounding lands ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcanoes Of The United States
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and periodic intervals of explosive eruptions and effusive eruptions, although some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and hardens before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high-to-intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less-viscous mafic magma. Extensive felsic lava flows are uncommon, but have travelled as far as . Stratovolcanoes are sometimes called composite volcanoes because of their composite stratified structure, built up from sequential outpourings of erupted materials. They are among the most common types of volcanoes, in contrast to the less common shield volcano ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes Of Alaska
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 sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountains Of Alaska
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable terrain and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountains Of Lake And Peninsula Borough, Alaska
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes Of Lake And Peninsula Borough, Alaska
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 slide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes Of Kodiak Island Borough, Alaska
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 slide pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountains Of Kodiak Island Borough, Alaska
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable terrain and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Volcanoes In The United States Of America
A list of volcanoes in the United States and its territories. Alaska American Samoa Arizona California Colorado Hawaii /[./[Https://www.sci.news/geology/puhahonu-shield-volcano-08435.html Puhahonu - - - Unknown Idaho Illinois Louisiana Michigan Mississippi Missouri Nevada New Hampshire New Jersey New Mexico Sierra Grande -. -. -. 2.41 to 2.88 million years ago Northern Mariana Islands Oregon Texas Utah Virginia Washington Wyoming See also *Geothermal energy in the United States *List of Cascade volcanoes *List of large volume volcanic eruptions in the Basin and Range Province * List of volcanoes in Canada *List of volcanoes in Mexico *List of volcanoes in Russia * List of volcanic craters in Alaska *List of volcanic craters in Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial.Oxford University Press – Why Geography Matters: More Than Ever (book) – "Holocene Humanity" section https://books.google.com/books?id=7P0_sWIcBNsC The Holocene corresponds with the rapid proliferation, growth and impacts of the human species worldwide, including all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valley Of Ten Thousand Smokes
The Valley of Ten Thousand Smokes is a valley within Katmai National Park and Preserve in Alaska which is filled with ash flow from the eruption of Novarupta on June 6–8, 1912. Following the eruption, thousands of fumaroles vented steam from the ash. Robert F. Griggs, who explored the volcano's aftermath for the National Geographic Society in 1916, gave the valley its name, saying that "the whole valley as far as the eye could reach was full of hundreds, no thousands—literally, tens of thousands—of smokes curling up from its fissured floor." Prior to the eruption, the area now called the Valley of Ten Thousand Smokes was an unremarkable and unnamed portion of the Ukak River valley. Although never permanently inhabited by humans, it served as a pass for the Alutiiq people, as well as animals such as grizzly bears. The 1912 eruption was the largest eruption by volume in the 20th century, erupting a magma volume of about . As many as 14 major earthquakes between M_\text ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
