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Tennaya Glacier
Tennaya Glacier is one of several glaciers draining the eastern side of the Mount Edziza ice cap in northwestern British Columbia, Canada. It is located southeast of the summit of Mount Edziza and northwest of Ice Peak at the head of Tennaya Creek. Meltwater from Tennaya Glacier feeds Tennaya Creek which eventually flows into Nuttlude Lake, an expansion of Kakiddi Creek. The name of the glacier was suggested by the Geological Survey of Canada on November 15, 1979, and eventually became official on November 24, 1980. ''Tennaya'' is derived from the Tahltan words ''ten'' and ''naya'', which mean ''ice'' and ''be come down'' respectively. The name of this glacier is a reference to a spectacular icefall at the head of Tennaya valley. Geology At the head of Tennaya Glacier are rocks assigned to the upper assemblage of the Ice Peak Formation. They consist of trachyte, benmoreite, mugearite, tristanite, trachybasalt and alkali basalt that are in the form of lava flows, lava dom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Glacier
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as crevasses and seracs, as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques, moraines, or fjords. Although a glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets (also known as "continental glaciers") in the polar regions, but glaciers may be found in mountain ranges on every continent other than the Australian mainland, including Oceania's high-latitude oceanic island countries such as New Zealand. Between latitudes 35°N and 35°S, glaciers occur only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trachybasalt
Trachybasalt is a volcanic rock with a composition between trachyte and basalt. It resembles basalt but has a high content of alkali metal oxides. Minerals in trachybasalt include alkali feldspar, calcic plagioclase, olivine, clinopyroxene and likely very small amounts of leucite or analcime. Description An aphanitic (fine-grained) igneous rock is classified as trachybasalt when it has a silica content of about 49% and a total alkali metal oxide content of about 6%. This places trachybasalt in the S1 field of the TAS diagram. Trachybasalt is further divided into sodium-rich '' hawaiite'' and potassium-rich ''potassic trachybasalt'', with wt% > + 2 for hawaiite. The intrusive equivalent of trachybasalt is monzonite. Trachybasalt is not defined on the QAPF diagram, which classifies crystalline igneous rock by its relative content of feldspars and quartz. However, the U.S. Geological Survey defines trachybasalt as a mafic volcanic rock (composed of over 35% mafic minerals) in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idiji Glacier
Idiji Glacier is one of several glaciers draining the eastern side of the Mount Edziza ice cap in northwestern British Columbia, Canada. It is located south of the summit of Mount Edziza in a cirque just southeast of Ice Peak. Idiji Glacier is separated from the much larger Tencho Glacier by a ridge that extends south of Ice Peak above the Idiji cirque headwall. Idiji Glacier is the namesake of Idiji Ridge which is just to the southeast. The name of the glacier was suggested by the Geological Survey of Canada on November 15, 1979, and eventually became official on November 24, 1980. ''Idiji'' means "it thunders" in the Tahltan language, which refers to the loud noises stemming from this very active glacier. At the head of Idiji Glacier are rocks assigned to the upper assemblage of the Ice Peak Formation. They consist of trachyte, benmoreite, mugearite, tristanite, trachybasalt and alkali basalt that are in the form of lava flows, lava domes and pyroclastic breccia. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Glaciers In Canada
This is a list of glaciers in Canada. List of glaciers Saint Elias Mountains *Donjek Glacier *Hubbard Glacier * Logan Glacier Coast Mountains Boundary Ranges * Juneau Icefield ** Llewellyn Glacier *Hang Ten Icefield *Stikine Icecap **Great Glacier * Andrei Icefield **Andrei Glacier **Choquette Glacier ** Hoodoo Glacier ** Johnson Glacier **Porcupine Glacier ** Twin Glacier * Salmon Glacier * Cambria Icefield Pacific Ranges *Monarch Icefield * Ha-Iltzuk Icefield **Klinaklini Glacier ** Silverthrone Glacier * Waddington Massif- Pantheon Range- Whitemantle Range ** Waddington Glacier ** Tiedemann Glacier ** Scimitar Glacier **Parallel Glacier **Franklin Glacier **Bell Glacier (Canada) ** Cannonade Glacier **Remote Glacier **Shadow Glacier ** Fan Glacier **Geddes Glacier ** Chaos Glacier ** Radiant Glacier **Cataract Glacier **Isolation Glacier ** Shiverick Glacier **Malemute Glacier ** Sunrise Glacier ** Tellot Glacier **Smoking Cannon Glacier **Jambeau Glacier **Chanterelle Gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Raven Formation
The Big Raven Formation is a stratigraphic unit of Quaternary age in northwestern British Columbia, Canada. It is the youngest and least voluminous geological formation of the Mount Edziza volcanic complex (MEVC); it overlies at least six older formations of this volcanic complex. The main volcanic rocks of the Big Raven Formation are alkali basalts and hawaiites, although a small volume of trachyte comprises the Sheep Track Member. These rocks were deposited by volcanic eruptions in the last 20,000 years during the Volcanism of the Mount Edziza volcanic complex#Fifth magmatic cycle, latest magmatic cycle of the MEVC. Alkali basalt and hawaiite are in the form of lava flows and small volcanic cones while trachyte of the Sheep Track Member is mainly in the form of volcanic ejecta which covers an area of about . The Big Raven Formation is widespread throughout the MEVC, occurring on or adjacent to the Arctic Lake Plateau, Arctic Lake, Big Raven Plateau, Big Raven and Kitsu Plateau, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trim Line
A trim line, also written as trimline, is a clear line on the side of a valley formed by a glacier. The line marks the most recent highest extent of the glacier. The line may be visible due to changes in color to the rock or to changes in vegetation on either side of the line. The term "trim line" is also used for similar looking phenomena caused by floods, volcanic activity, or tsunamis A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater expl ....Steven DutchGiant Waves in Lituya Bay, Alaska USGS PP 354-C References {{Glaciology-stub Glaciers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ash Flow
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of but is capable of reaching speeds up to . The gases and tephra can reach temperatures of about . Pyroclastic flows are the most deadly of all volcanic hazards and are produced as a result of certain explosive eruptions; they normally touch the ground and hurtle downhill, or spread laterally under gravity. Their speed depends upon the density of the current, the volcanic output rate, and the gradient of the slope. Origin of term The word ''pyroclast'' is derived from the Greek (''pýr''), meaning "fire", and (''klastós''), meaning "broken in pieces". A name for pyroclastic flows which glow red in the dark is (French, "burning cloud"); this was notably used to describe the disastrous 1902 eruption of Mount Pelée on Martinique, a French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lahar
A lahar (, from jv, ꦮ꧀ꦭꦲꦂ) is a violent type of mudflow or debris flow composed of a slurry of pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a river valley. Lahars are extremely destructive: they can flow tens of metres per second, they have been known to be up to deep, and large flows tend to destroy any structures in their path. Notable lahars include those at Mount Pinatubo and Nevado del Ruiz, the latter of which killed thousands of people in the town of Armero. Etymology The word ''lahar'' is of Javanese origin. Berend George Escher introduced it as a geological term in 1922. Description The word ''lahar'' is a general term for a flowing mixture of water and pyroclastic debris. It does not refer to a particular rheology or sediment concentration. Lahars can occur as normal stream flows (sediment concentration of less than 30%), hyper-concentrated stream flows (sediment concentration between 30 and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edziza Formation
The Edziza Formation is a stratigraphic unit of Pleistocene age in northwestern British Columbia, Canada. First described in 1984, the Edziza Formation was mapped as one of several geological formations of the Mount Edziza volcanic complex. It overlies at least four other geological formations of this volcanic complex that differ in age and composition. The main volcanic rock comprising the Edziza Formation is trachyte which was deposited by volcanic eruptions at the end of the Volcanism of the Mount Edziza volcanic complex#Third magmatic cycle, third magmatic cycle of the Mount Edziza volcanic complex 0.9 million years ago. Trachyte of the Edziza Formation is in the form of lava flows and pyroclastic rocks that comprise the central stratovolcano of Mount Edziza, as well as lava domes on its summit and flanks. At least four lava lakes ponded inside the summit volcanic crater, crater which cooled into four rock units that are exposed in the breached eastern crater rim. These lava l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comenditic
Comendite is a hard, peralkaline igneous rock, a type of light blue grey rhyolite. Phenocrysts are sodic sanidine with minor albite and bipyramidal quartz.Joseph P. Iddings, Iddings, Joseph Paxson, 1913, ''Igneous rocks: composition, texture and classification'', v. 2, pp. 94-96 Comendite occurs in the mountains Tibrogargan, Coonowrin, Tunbubudla, Coochin, Saddleback, Tibberoowuccum and Ngungun in the Glass House Mountains, South East Queensland, Australia. The blue colour is caused by very small crystals of riebeckite or arfvedsonite. Comendite also occurs in Sardinia, Corsica, Ascension Island, Ethiopia, Somalia and other areas of East Africa. The 1903 eruption of Baekdu Mountain, Changbaishan volcano in north-east China erupted comendite pumice. Comendite derives its name from the area of Le Commende on San Pietro Island in Italy, where the rock type is found.Cioni, R. and Funedda, A., (2005) ''Structural geology of crystal-rich, silicic lava flows: A case study from San Pietro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breccia
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, tectonic breccia, igneous breccia, impact breccia, and hydrothermal breccia. A megabreccia is a breccia composed of very large rock fragments, sometimes kilometers across, which can be formed by landslides, impact events, or caldera collapse. Types Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. These indicate that the gravel was deposited very close to its source area, since other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
