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Subglacial Volcanoes
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 a flattened top an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subglacial Eruption-numbers
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 common i ... {{Disambiguation Glaciology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Lake Outburst Flood
A glacial lake outburst flood (GLOF) is a type of outburst flood caused by the failure of a dam containing a glacial lake. An event similar to a GLOF, where a body of water contained by a glacier melts or overflows the glacier, is called a jökulhlaup. The dam can consist of glacier ice or a terminal moraine. Failure can happen due to erosion, a buildup of water pressure, an avalanche of rock or heavy snow, an earthquake or cryoseism, volcanic eruptions under the ice, or massive displacement of water in a glacial lake when a large portion of an adjacent glacier collapses into it. Increasing glacial melting because of climate change, alongside other environmental effects of climate change (i.e. permafrost melting) mean that regions with glaciers are likely to see increased flooding risks from GLOFs. This is especially true in the Himalayas where geologies are more active. A 2023 study found 15 million people at risk from this hazard, mostly in China, India, Nepal, Pakistan, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pine Island Glacier
Pine Island Glacier (PIG) is a large ice stream, and the fastest melting glacier in Antarctica. responsible for about 13% of Antarctica's ice loss. The glacier flows west-northwest along the south side of the Hudson Mountains into Pine Island Bay, part of the Amundsen Sea. The area drained by Pine Island Glacier comprises about 10% of the West Antarctic Ice Sheet. Satellite measurements have shown that the Pine Island Glacier Basin has a greater net contribution of ice to the sea than any other ice drainage basin in the world and this has increased due to recent acceleration of the ice stream. In recent years, the flow of the glacier has accelerated and the grounding line has retreated. Since 2015, the calving of very large icebergs from the Pine Island Glacier has become a roughly annual event. The largest such iceberg, Iceberg B-46, had an initial size of . The glacier is extremely remote, but scientists have surveyed the ice with radar, GPS, and seismic sensors. Most of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hudson Mountains
The Hudson Mountains are a mountain range in western Ellsworth Land just east of Pine Island Bay at the Walgreen Coast of the Amundsen Sea. They are of volcanic origin, consisting of low scattered mountains and nunataks that protrude through the West Antarctic Ice Sheet. The Hudson Mountains are bounded on the north by Cosgrove Ice Shelf and on the south by Pine Island Glacier. The mountains were volcanically active during the Miocene and Pliocene, but there is evidence for an eruption about two millennia ago and uncertain indications of activity in the 20th century. Geography and geomorphology The Hudson Mountains rise in western Ellsworth Land of West Antarctica and were discovered in 1940 by the United States Antarctic Service Expedition. The mountains lie at some distance from the Amundsen Sea's Walgreen Coast, facing Pine Island Bay. The Cosgrove Ice Shelf lies north of the Hudson Mountains. The mountains are remote and visits are rare. In 1991, they were prospe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerial Survey
Aerial survey is a method of collecting geomatics or other imagery data using airplanes, helicopters, unmanned aerial vehicle, UAVs, Balloon (aeronautics), balloons, or other aerial methods. Typical data collected includes aerial photography, Lidar, remote sensing (using various visible and invisible bands of the electromagnetic spectrum, such as infrared, gamma ray, gamma, or ultraviolet) and geophysical data (such as aeromagnetic surveys and gravity measurements). It can also refer to a chart or map made by analyzing a region from the air. Aerial survey should be distinguished from satellite imagery technologies because of its better resolution, quality, and resistance to Atmosphere of Earth, atmospheric conditions that can negatively impact and obscure Earth observation satellite, satellite observation. Today, aerial survey is often recognized as a synonym for aerophotogrammetry, a part of photogrammetry where the camera is airborne. Measurements on aerial images are provided b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is commonly defined as a vent or fissure 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 because most of Earth's plate boundaries are underwater, most volcanoes 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 resulting from divergent tectonic activity are usually non-explosive whereas those resulting from convergent tectonic activity cause violent eruptions."Mid-ocean ridge tectonics, volcanism and geomorphology." Geology 26, no. 455 (2001): 458. https://macdonald.faculty.geol.ucsb.edu/papers/Macdonald%20Mid-Ocean%20Ridge%20Tectonics.pdf Volcanoes can also form where there is str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature Geoscience
''Nature Geoscience'' is a monthly peer-reviewed scientific journal published by the Nature Publishing Group. The Chief Editor is Tamara Goldin, who took over from Heike Langenberg in February 2020. It was established in January 2008. Scope The journal covers all aspects of the Earth sciences, including theoretical research, modelling, and field work. Significant related work in other fields, such as atmospheric sciences, geology, geophysics, climatology, oceanography, palaeontology, and space science, is also published. Abstracting and indexing The journal is abstracted and indexed by: * '' CAB Abstracts'' * ''Chemical Abstracts Service/ CASSI'' * ''Science Citation Index'' * ''Current Contents/Physical, Chemical & Earth Sciences'' * '' GeoRef'' According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Antarctic Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of list of global issues, global issues, and to provide an active presence in the Antarctic on behalf of the UK. It is part of the Natural Environment Research Council (NERC). With over 400 staff, BAS takes an active role in Antarctic affairs, operating five research stations, one ship and five aircraft in both polar regions, as well as addressing key global and regional issues. This involves joint research projects with over 40 UK universities and more than 120 national and international collaborations. Having taken shape from activities during World War II, it was known as the Falkland Islands Dependencies Survey until 1962. History Operation Tabarin was a small British expedition in 1943 to establish permanently occupied bases in the Antarctic. It was a joint undertaking by the British Admiralty, Admiralt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Science Foundation
The U.S. National Science Foundation (NSF) is an Independent agencies of the United States government#Examples of independent agencies, independent agency of the Federal government of the United States, United States federal government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health. With an annual budget of about $9.9 billion (fiscal year 2023), the NSF funds approximately 25% of all federally supported basic research conducted by the List of American institutions of higher education, United States' colleges and universities. In some fields, such as mathematics, computer science, economics, and the social sciences, the NSF is the major source of federal backing. NSF's director and deputy director are appointed by the president of the United States and Advice and consent, confirmed by the United States Senate, whereas the 24 president-appointed members of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jökulhlaup
A jökulhlaup ( ) (literally "glacial run") is a type of glacial outburst flood. It is an Icelandic term that has been adopted in glaciological terminology in many languages. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland, which are triggered by geothermal heating and occasionally by a volcanic subglacial eruption, but it is now used to describe any large and abrupt release of water from a subglacial or proglacial lake/reservoir. Since jökulhlaups emerge from hydrostatically sealed lakes with floating levels far above the threshold, their peak discharge can be much larger than that of a marginal or extra-marginal lake burst. The hydrograph of a jökulhlaup from Vatnajökull typically either climbs over a period of weeks with the largest flow near the end, or it climbs much faster during the course of some hours. These patterns are suggested to reflect channel melting, and sheet flow under the front, respectively. Similar p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Table (landform)
A tableland is an area containing elevated landforms characterized by a distinct, flat, nearly level, or gently undulating surface. They often exhibit steep, cliff-like edges, known as escarpments, that separate them from surrounding lowlands. Depending on either their size, other physical characteristics, or geographic location, the landforms comprising a tableland are individually referred to by a number of names including butte, mesa, plateau, potrero, tepui, or tuya. A homologous landform under the sea is called either a tablemount or guyot. Sedimentary tablelands Sedimentary tablelands are tablelands that typically have developed from the erosion of coarse-grained, clastic, sedimentary rocks in the form of relatively flat-lying sandstones and conglomerates that have not been strongly deformed by tectonics. The primary control on the geomorphology of sedimentary tablelands is the dip of the layers of the sandstones, conglomerates, and associated sedimentary strata. Sedim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bill Mathews
William Henry Mathews (1919–2003) was a Canadian geologist, volcanologist, engineer, and professor. He is considered a pioneer in the study of subglacial eruptions and volcano-ice interactions in North America. Many of his publications continue to be regarded as classics in their field. Biography Bill Mathews was born in Vancouver, British Columbia in 1919. His mother and a brother died when he was two; his father, Vancouver pioneer Thomas Mathews, died when he was 13. Mathews attended King George Secondary School before entering the University of British Columbia in 1935, earning a Bachelor of Applied Science in geological engineering in 1940, followed by a Master of Applied Science with a major in petrology and a minor in physics in 1941. During college, he served as a student assistant for the Geological Survey of Canada from 1938 to 1941, and was also an instructor in the mountain infantry school of the Alpine Club of Canada, training personnel for the Canadian armed forc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
