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Polychrome Mountain
Polychrome Mountain is a prominent 5,900+ ft (1,798+ m) elevation summit located in Denali National Park and Preserve, in the Alaska Range, in the U.S. state of Alaska. It is a landmark in the Toklat River valley visible to tourists as the park road traverses the southern slope of the mountain. Polychrome Mountain is situated one mile north of Polychrome Pass, and northeast of Divide Mountain. Although modest in elevation, relief is significant since the peak rises nearly above the surrounding valley floor in less than two miles. This mountain's descriptive name, meaning "many colors", was first published in 1954 by the U.S. Geological Survey, and is taken from the pass with the same name.''Dictionary of Alaska Place Names'', Donald J. Orth author, United States Government Printing Office (1967), page 766. Geology About sixty million years ago, the mountain was part of a low plain composed of deep beds of gravel covered by ancient plants and varied animal life. The plain was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaska Range
The Alaska Range is a relatively narrow, 600-mile-long (950 km) mountain range in the southcentral region of the U.S. state of Alaska, from Lake Clark at its southwest endSources differ as to the exact delineation of the Alaska Range. ThBoard on Geographic Namesentry is inconsistent; part of it designates Iliamna Lake as the southwestern end, and part of the entry has the range ending at the Telaquana and Neacola Rivers. Other sources identify Lake Clark, in between those two, as the endpoint. This also means that the status of the Neacola Mountains is unclear: it is usually identified as the northernmost subrange of the Aleutian Range, but it could also be considered the southernmost part of the Alaska Range. to the White River in Canada's Yukon Territory in the southeast. The highest mountain in North America, Denali, is in the Alaska Range. It is part of the American Cordillera. The Alaska range is one of the higher ranges in the world after the Himalayas and the Ande ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Köppen Climate Classification
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notably in 1918 and 1936. Later, the climatologist Rudolf Geiger (1894–1981) introduced some changes to the classification system, which is thus sometimes called the Köppen–Geiger climate classification system. The Köppen climate classification divides climates into five main climate groups, with each group being divided based on seasonal precipitation and temperature patterns. The five main groups are ''A'' (tropical), ''B'' (arid), ''C'' (temperate), ''D'' (continental), and ''E'' (polar). Each group and subgroup is represented by a letter. All climates are assigned a main group (the first letter). All climates except for those in the ''E'' group are assigned a seasonal precipitation subgroup (the second letter). For example, ''Af'' indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountains Of Denali National Park And Preserve
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountains Of Denali 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Alaska
The geology of Alaska includes Precambrian igneous and metamorphic rocks formed in offshore terranes and added to the western margin of North America from the Paleozoic through modern times. The region was submerged for much of the Paleozoic and Mesozoic and formed extensive oil and gas reserves due to tectonic activity in the Arctic Ocean. Alaska was largely ice free during the Pleistocene, allowing humans to migrate into the Americas. Geologic History, Stratigraphy & Tectonics Compared with other areas of the North American continent, Alaska formed in the recent geologic past. Until 200 million years ago, western North America terminated at the Rocky Mountains, 120 miles further inland than the current shoreline, until the addition of the Yukon-Tanana Terrane. The Birch Creek Schist is the oldest rock in Alaska's interior and forms the core of the Yukon-Tanana Terrane with muscovite-quartz schist, mica quartzite and graphite schist. This intensely folded and rock unit extends f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanana River
The Tanana River ( Lower Tanana: Tth'eetoo', Upper Tanana: ''Tth’iitu’ Niign'') is a tributary of the Yukon River in the U.S. state of Alaska. According to linguist and anthropologist William Bright, the name is from the Koyukon (Athabaskan) ''tene no'', ''tenene'', literally "trail river". The river's headwaters are located at the confluence of the Chisana and Nabesna rivers just north of Northway in eastern Alaska. The Tanana flows in a northwest direction from near the border with the Yukon Territory, and laterally along the northern slope of the Alaska Range, roughly paralleled by the Alaska Highway. In central Alaska, it emerges into a lowland marsh region known as the Tanana Valley and passes south of the city of Fairbanks. In the marsh regions it is joined by several large tributaries, including the Nenana (near the city of Nenana) and the Kantishna. It passes the village of Manley Hot Springs and empties into the Yukon near the town of Tanana. Ice on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toklat River
The Toklat River ( taa, Tootl'o Huno) is an tributary of the Kantishna River in central Alaska in the United States It drains an area on the north slope of the Alaska Range on the south edge of the Tanana Valley southwest of Fairbanks. It issues from unnamed glaciers in the northern Alaska Range in Denali National Park and Preserve, northeast of Denali. It flows generally northwest through hilly country to the tundra to the north of the Alaska Range. The river was described as the ''Toclat'' by Lt. H.T. Allen in 1885. Other names or variants include ''Tootl'ot Huno'', ''Tootl'ot Huno' Hutl'ot'', ''Tootl'ot No' '' and ''Tutlut River''. Depth of 50 ft, width of 25 ft Gallery See also *List of rivers of Alaska This is a List of rivers in Alaska, which are at least fifth-order according to the Strahler method of stream classification, and an incomplete list of otherwise-notable rivers and streams. Alaska has more than 12,000 rivers, and thousands more st ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Runoff
Surface runoff (also known as overland flow) is the flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil. This can occur when the soil is saturated by water to its full capacity, and the rain arrives more quickly than the soil can absorb it. Surface runoff often occurs because impervious areas (such as roofs and pavement) do not allow water to soak into the ground. Furthermore, runoff can occur either through natural or man-made processes. Surface runoff is a major component of the water cycle. It is the primary agent of soil erosion by water. The land area producing runoff that drains to a common point is called a drainage basin. Runoff that occurs on the ground surface before reaching a channel can be a nonpoint source of pollution, as it can carry man-made contaminants or natural forms of pollution (such as rotting leaves). Man-made contaminants in run ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subarctic Climate
The subarctic climate (also called subpolar climate, or boreal climate) is a climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of an ocean, generally at latitudes from 50° to 70°N, poleward of the humid continental climates. Subarctic or boreal climates are the source regions for the cold air that affects temperate latitudes to the south in winter. These climates represent Köppen climate classification ''Dfc'', ''Dwc'', ''Dsc'', ''Dfd'', ''Dwd'' and ''Dsd''. Description This type of climate offers some of the most extreme seasonal temperature variations found on the planet: in winter, temperatures can drop to below and in summer, the temperature may exceed . However, the summers are short; no more than three months of the year (but at least one month) must have a 24-hour average temperature of at least to fall into this category of climate, and the coldest month should ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intrusive Rock
Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form '' intrusions'', such as batholiths, dikes, sills, laccoliths, and volcanic necks.Intrusive RocksIntrusive rocks accessdate: March 27, 2017.Igneous intrusive rocks, accessdate: March 27, 2017.Britannica.comintrusive rock , geology , Britannica.com accessdate: March 27, 2017. Intrusion is one of the two ways igneous rock can form. The other is extrusion, such as a volcanic eruption or similar event. An intrusion is any body of intrusive igneous rock, formed from magma that cools and solidifies within the crust of the planet. In contrast, an ''extrusion'' consists of extrusive rock, formed above the surface of the crust. Some geologists use the term plutonic rock synonymously with intrusive rock, but other geologists subdivide intrusive rock, by crystal size, into coarse-grained plutonic rock (typically formed deeper in the Earth's crust in batholiths or stocks) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denali National Park And Preserve
Denali National Park and Preserve, formerly known as Mount McKinley National Park, is an American national park and preserve located in Interior Alaska, centered on Denali, the highest mountain in North America. The park and contiguous preserve encompass which is larger than the state of New Hampshire. On December 2, 1980, Denali Wilderness was established within the park. Denali's landscape is a mix of forest at the lowest elevations, including deciduous taiga, with tundra at middle elevations, and glaciers, snow, and bare rock at the highest elevations. The longest glacier is the Kahiltna Glacier. Wintertime activities include dog sledding, cross-country skiing, and snowmobiling. The park received 594,660 recreational visitors in 2018. History Prehistory and protohistory Human habitation in the Denali Region extends to more than 11,000 years before the present, with documented sites just outside park boundaries dated to more than 8,000 years before the present. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
