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Rainbow Range (Coast Mountains)
The Rainbow Range, formerly gazetted as the Rainbow Mountains, is a mountain range in British Columbia, Canada, located northwest of Anahim Lake. Located on the western edge of the Chilcotin Plateau, the range adjoins the Coast Mountains Pacific Ranges to the south, and the Kitimat Ranges to the north. In some classification systems it is considered part of the Coast Mountains. It lies north of the Bella Coola and Atnarko Rivers and south and west of the Dean River, which curves around its north flank, and is relatively drier in climate and easier of terrain than more mountainous areas immediately west. Once called Tsitsutl, meaning "rainbow mountains" in the Ulkatcho dialect of the Carrier language, that name is now the name of the range's highest peak. Geology The Rainbow Range is an eight-million-year-old (Miocene) massive peralkaline shield volcano in the Anahim Volcanic Belt which includes the lower but similar Itcha and Ilgachuz Ranges. The shield has a diameter of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Provinces And Territories Of Canada
Within the geographical areas of Canada, the ten provinces and three territories are sub-national administrative divisions under the jurisdiction of the Canadian Constitution. In the 1867 Canadian Confederation, three provinces of British North America—New Brunswick, Nova Scotia, and the Province of Canada (which upon Confederation was divided into Ontario and Quebec)—united to form a federation, becoming a fully independent country over the next century. Over its history, Canada's international borders have changed several times as it has added territories and provinces, making it the world's second-largest country by area. The major difference between a Canadian province and a territory is that provinces receive their power and authority from the ''Constitution Act, 1867'' (formerly called the ''British North America Act, 1867''), whereas territorial governments are creatures of statute with powers delegated to them by the Parliament of Canada. The powers flowing from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dean River
The Dean River is one of the major rivers of the Kitimat Ranges subrange of the southern Coast Mountains in British Columbia. It begins at Aktaklin Lake on the Chilcotin Plateau and winds north around the Rainbow Range to enter Dean Channel at the now-uninhabited, remote community of Kimsquit. It is one of the few rivers to fully penetrate the wall of the Coast Mountains between the Fraser's mouth (near Vancouver) and the mouth of the Skeena River (near Prince Rupert). The Dean River is known as one of the best fisheries for steelhead Steelhead, or occasionally steelhead trout, is the common name of the anadromous form of the coastal rainbow trout or redband trout (O. m. gairdneri). Steelhead are native to cold-water tributaries of the Pacific basin in Northeast Asia and ... in the world. References Rivers of the Kitimat Ranges Rivers of the Central Coast of British Columbia Rivers of the Chilcotin Range 3 Coast Land District {{BritishColumbia-river-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaiian Islands
The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kure Atoll. Formerly the group was known to Europeans and Americans as the Sandwich Islands, a name that James Cook chose in honor of the 4th Earl of Sandwich, the then First Lord of the Admiralty. Cook came across the islands by chance when crossing the Pacific Ocean on his Third Voyage in 1778, on board HMS ''Resolution''; he was later killed on the islands on a return visit. The contemporary name of the islands, dating from the 1840s, is derived from the name of the largest island, Hawaii Island. Hawaii sits on the Pacific Plate and is the only U.S. state that is not geographically connected to North America. It is part of the Polynesia subregion of Oceania. The state of Hawaii occupies the archipelago almost in its entirety (includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hotspot (geology)
In geology, hotspots (or hot spots) are volcanic locales thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Examples include the Hawaii, Iceland, and Yellowstone hotspots. A hotspot's position on the Earth's surface is independent of tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. The alternative plate theory is that the mantle source beneath a hotspot is not anomalously hot, rather the crust above is unusually weak or thin, so that lithospheric extension permits the passive rising of melt from shallow depths. Origin The origins of the concept of hotspots lie in the work of J. Tuzo Wilson, who postulated in 1963 that the formation of the Hawaiian Islands resulted from the slow movement of a tecton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American Plate
The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacific Plate (which borders the plate to the west). It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust. The interior of the main continental landmass includes an extensive granitic core called a craton. Along most of the edges of this craton are fragments of crustal material called terranes, which are accreted to the craton by tectonic actions over a long span of time. It is thought that much of North America west of the Rocky Mountains is composed of such terranes. Boundaries The southern boundary with the Cocos Plate to the west and the Caribbean Plate to the east is a transform fault, represented by the Swan Islands Transform Fault unde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand, for example, aragonite, which has mostly been created, over the past 500million years, by various forms of life, like coral and shellfish. For example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Somewhat more rarely, sand may be composed of calciu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Rock
Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element of some sediments and sedimentary rocks. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of Precambrian shield geology, the term "volcanic" is often applied to what are strictly metavolcanic rocks. Volcanic rocks and sediment that form from magma erupted into the air are called "volcaniclastics," and these are technically sedimentary rocks. Volcanic rocks are among the most common rock types on Earth's surface, particularly in the oceans. On land, they are very common at plate boundaries and in flood basalt provinces. It has been estimated t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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#Glaciology, ablation over many years, often Century, centuries. It acquires distinguishing features, such as Crevasse, crevasses and Serac, 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 lati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itcha Range
The Itcha Range, also known as the Itchas, is a small isolated mountain range in the West-Central Interior of British Columbia, Canada. It is located northeast of the community of Anahim Lake. With a maximum elevation of , it is the lowest of three mountain ranges on the Chilcotin Plateau extending east from the Coast Mountains. Two mountains are named in the Itcha Range; Mount Downton and Itcha Mountain. A large provincial park surrounds the Itcha Range and other features in its vicinity. More than 15 animal species are known to exist in the Itcha Range area, as well as a grassland community that is limited only to this location of British Columbia. The Itcha Range is within territory which has been occupied by aboriginal peoples for millennia. This area has a relatively dry environment compared to the Coast Mountains in the west. In contrast to most mountain ranges in British Columbia, the Itcha Range represents an inactive shield volcano. This highly dissected volcanic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anahim Volcanic Belt
The Anahim Volcanic Belt (AVB) is a west–east trending chain of volcanoes and related magmatic features in British Columbia, Canada. It extends from Athlone Island on the Central Coast, running eastward through the strongly uplifted and deeply dissected Coast Mountains to near the community of Nazko on the Interior Plateau. The AVB is delineated as three west-to-east segments that differ in age and structure. A wide variety of igneous rocks with differing compositions occur throughout these segments, comprising landforms such as volcanic cones, volcanic plugs, lava domes, shield volcanoes and intrusions. Volcanic activity has occurred repeatedly in the AVB for the last 15 million years, during which time three major magmatic episodes took place 15–13, 9–6 and 3–1 million years ago. These major magmatic episodes are represented by plutons, dike swarms, volcanic fields and large shield volcanoes. Volcanic activity in the last 1 million years has been relatively minor an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shield Volcano
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes are found wherever fluid low-silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include the largest volcanoes on earth, such as Tamu Massif and Mauna Loa. Giant shield volcanoes are found on other planets of the Solar System, including Olympus Mons on Mars and Sapas Mons on Venus. Etymology The term 'shield volcano' is taken from the German term ''Schildvulkan'', coined by the Austrian geologist Eduard Suess in 1888 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peralkaline
Peralkaline rocks include those igneous rocks which have a deficiency of aluminium such that sodium and potassium are in excess of that needed for feldspar. The presence of aegerine (sodium pyroxene) and riebeckite (sodium amphibole) are indicative of peralkaline conditions. Examples are the peralkaline rhyolites, comendite and pantellerite, with comendite being the more felsic (silica-rich) rock. Another example is the peralkaline granite that forms the islet of Rockall in the North Atlantic Ocean. Peralkaline rocks are indicative of continental rift-related volcanicity (e.g. the peralkaline rhyolites of the East African Rift in central Kenya) as well as continental and oceanic hotspot volcanicity (e.g. the peralkaline rhyolites of the Glass House Mountains in eastern Australia and the Canary Islands in the Atlantic Ocean). Peralkaline rocks related to subduction zone volcanicity have also been reported (e.g. Sardinia in Italy). Peralkaline magmas likely form when fractional crys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
