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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] |
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] |
Mugearite
Mugearite () is a type of oligoclase-bearing basalt, comprising olivine, apatite, and opaque oxides. The main feldspar in mugearite is oligoclase. Mugearite is a sodium-rich member of the alkaline magma series. In the TAS classification of volcanic rock, mugearite is classified as sodium-rich basaltic trachyandesite. Examples Western Scotland Mugearite was first identified at Mugeary on the island of Skye, Scotland by Alfred Harker in 1904. Outcrops of mugearite also occur on the island of Isle of Mull, Mull. These examples of mugearite were formed during a period of continental flood basalt volcanic activity that happened in western Scotland during the Paleogene Period (geology), period of the Earth's geological history, when the North Atlantic Ocean opened between Europe and North America. Oceanic islands Mugearite has been erupted by the volcanoes of some High island, oceanic islands at Hotspot (geology), hotspots. Examples are Hawaii (island), Hawaii, Ascension Island, Sai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenchen Glacier
Tenchen Glacier is located on the eastern flank of Mount Edziza in northwestern British Columbia, Canada. It lies within an immense cirque whose headwall has breached the eastern side of Mount Edziza's summit volcanic crater, crater. At the head of Tenchen Glacier are icefalls that drape down shear, cliffs from the breached eastern crater rim; permanent ice fills the summit crater. Meltwater from Tenchen Glacier feeds Tenchen Creek which eventually merges with Kakiddi Creek. The name of the glacier was suggested by the Geological Survey of Canada on November 19, 1979, and eventually became official on November 24, 1980. ''Tenchen'' is derived from the Tahltan words ''ten'' and ''chen'', which mean ''ice'' and ''dirty'' respectively. The name of this glacier is a reference to its debris-covered surface. Geology The Tenchen cirque is the product of erosion that gradually enlarged an initial scar formed by an explosive eruption that blew away part of the eastern summit crater rim. H ... [...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 G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Crater
A volcanic crater is an approximately circular depression in the ground caused by Volcano, volcanic activity. It is typically a bowl-shaped feature containing one or more vents. During Types of volcanic eruptions, volcanic eruptions, molten magma and volcanic gases rise from an underground magma chamber, through a conduit, until they reach the crater's vent, from where the gases escape into the atmosphere and the magma is erupted as lava. A volcanic crater can be of large dimensions, and sometimes of great depth. During certain types of explosive eruptions, a volcano's magma chamber may empty enough for an area above it to subside, forming a type of larger depression known as a caldera. Geomorphology In most volcanoes, the crater is situated at the top of a mountain formed from the erupted volcanic deposits such as lava flows and tephra. Volcanoes that terminate in such a summit crater are usually of a conical form. Other volcanic craters may be found on the flanks of volcanoe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuff
Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as tuffaceous (for example, ''tuffaceous sandstone''). Tuff composed of sandy volcanic material can be referred to as volcanic sandstone. Tuff is a relatively soft rock, so it has been used for construction since ancient times. Because it is common in Italy, the Romans used it often for construction. The Rapa Nui people used it to make most of the ''moai'' statues on Easter Island. Tuff can be classified as either igneous or sedimentary rock. It is usually studied in the context of igneous petrology, although it is sometimes described using sedimentological terms. Tuff is often erroneously called tufa in guidebooks and in television programmes. Volcanic ash The material that is expelled in a volcanic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacustrine
A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much larger oceans, they do form part of the Earth's water cycle. Lakes are distinct from lagoons, which are generally coastal parts of the ocean. Lakes are typically larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which usually flow in a channel on land. Most lakes are fed and drained by rivers and streams. Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. Some parts of the world have many lakes formed by the chaotic drainage patterns left over from the last ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bed (geology)
In geology, a bed is a layer of sediment, sedimentary rock, or pyroclastic material "bounded above and below by more or less well-defined bedding surfaces".Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds., 2005. ''Glossary of Geology'' (5th ed.). Alexandria, Virginia; American Geological Institute. p 61. Specifically in sedimentology, a bed can be defined in one of two major ways.Davies, N.S., and Shillito, A.P. 2021, ''True substrates: the exceptional resolution and unexceptional preservation of deep time snapshots on bedding surfaces.'' ''Sedimentology.'' published online 22 May 2021, doi: 10.1111/sed.12900. First, Campbell and Reineck and SinghReineck, H.E., and Singh, I.B., 1980. ''Depositional Sedimentary Environments'', (2nd ed.) Berlin, Germany: Springer-Verlag, 504 pp. use the term ''bed'' to refer to a thickness-independent layer comprising a coherent layer of sedimentary rock, sediment, or pyroclastic material bounded above and below by surfaces known as beddi ... [...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 otherwise th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic Rock
Pyroclastic rocks (derived from the el, πῦρ, links=no, meaning fire; and , meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts. Pyroclastic rocks are a type of volcaniclastic deposit, which are deposits made predominantly of volcanic particles. 'Phreatic' pyroclastic deposits are a variety of pyroclastic rock that forms from volcanic steam explosions and they are entirely made of accidental clasts. 'Phreatomagmatic' pyroclastic deposits are formed from explosive interaction of magma with groundwater. Unconsolidated accumulations of pyroclasts are described as tephra. Tephra may become lithified to a pyroclastic rock by cementation or chemical reactions as the result of the passage of hot gases (fumarolic alteration) or groundwater (e.g. hydrothermal alteration and diagenesis) and burial, or, if it is emplaced at temperatures so hot that the soft glassy pyrocl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Dome
In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on Earth are lava dome forming. The geochemistry of lava domes can vary from basalt (e.g. Semeru, 1946) to rhyolite (e.g. Chaiten, 2010) although the majority are of intermediate composition (such as Santiaguito, dacite-andesite, present day) The characteristic dome shape is attributed to high viscosity that prevents the lava from flowing very far. This high viscosity can be obtained in two ways: by high levels of silica in the magma, or by degassing of fluid magma. Since viscous basaltic and andesitic domes weather fast and easily break apart by further input of fluid lava, most of the preserved domes have high silica content and consist of rhyolite or dacite. Existence of lava domes has been suggested for some domed structures on the Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
