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Rampart Dam
The Rampart Dam or Rampart Canyon Dam was a project proposed in 1954 by the U.S. Army Corps of Engineers to dam the Yukon River in Alaska for hydroelectric power. The project was planned for Rampart Canyon (also known as Rampart Gorge) just southwest of the village of Rampart, Alaska, about west-northwest of Fairbanks. The resulting dam would have created a lake roughly the size of Lake Erie, making it the largest man-made reservoir in the world. The plan for the dam itself called for a concrete structure high with a top length of about . The proposed power facilities would have consistently generated between 3.5 and 5.0gigawatts of electricity, based on the flow of the river as it differs between winter and summer. Though supported by many politicians and businesses in Alaska, the project was canceled after objections were raised. Native Alaskans in the area protested the threatened loss of nine villages that would be flooded by the dam. Conservation groups abhorred the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yukon River
The Yukon River (Gwichʼin language, Gwich'in: ''Ųųg Han'' or ''Yuk Han'', Central Alaskan Yup'ik language, Yup'ik: ''Kuigpak'', Inupiaq language, Inupiaq: ''Kuukpak'', Deg Xinag language, Deg Xinag: ''Yeqin'', Hän language, Hän: ''Tth'echù'' or ''Chuu k'onn'', Southern Tutchone: Chu Nìikwän, russian: Юкон, Yukon) is a major watercourse of northwestern North America. From its source in British Columbia, Canada, it flows through Canada's territory of Yukon (itself named after the river). The lower half of the river continues westwards through the U.S. state of Alaska. The river is long and empties into the Bering Sea at the Yukon–Kuskokwim Delta. The average flow is . The total drainage area is , of which lies in Canada. The total area is more than 25% larger than Texas or Alberta. The longest river in Alaska and Yukon, it was one of the principal means of transportation during the 1896–1903 Klondike Gold Rush. A portion of the river in Yukon—"The Thirty Mile" se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yukon Flats National Wildlife Sanctuary
The Yukon Flats National Wildlife Refuge is a protected wetland area in the U.S. state of Alaska. It encompasses most of the Yukon Flats, a vast wetland area centered on the confluence of the Yukon River, Porcupine River, and Chandalar River. The area is a major waterfowl breeding ground, and after a proposal to flood the Yukon Flats via Rampart Dam, a dam on the Yukon River was turned down, the Yukon Flats were deemed worthy of protection. On 1 December 1978, US President Jimmy Carter designated the Yukon Flats as a National Monument on the basis of the Antiquities Act of 1906. In the course of the Alaska National Interest Lands Conservation Act of December 2, 1980, the area boundaries were changed after political criticism and the status was downgraded to that of a wildlife refuge. It is the third-largest National Wildlife Refuge in the United States, although it is less than one-half the size of either of the two largest, the Arctic National Wildlife Refuge, or the Yukon De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defining the val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Igneous Rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. The magma can be derived from Partial melting, partial melts of existing rocks in either a Terrestrial planet, planet's mantle (geology), mantle or crust (geology), crust. Typically, the melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive (geology), extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, or without crystallization to form Volcanic glass, natural glasses. Igneous rocks occur in a wide range of geological settings: shields, platforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richter Scale
The Richter scale —also called the Richter magnitude scale, Richter's magnitude scale, and the Gutenberg–Richter scale—is a measure of the strength of earthquakes, developed by Charles Francis Richter and presented in his landmark 1935 paper, where he called it the "magnitude scale". This was later revised and renamed the local magnitude scale, denoted as ML or . Because of various shortcomings of the original scale, most seismological authorities now use other similar scales such as the moment magnitude scale () to report earthquake magnitudes, but much of the news media still erroneously refers to these as "Richter" magnitudes. All magnitude scales retain the logarithmic character of the original and are scaled to have roughly comparable numeric values (typically in the middle of the scale). Due to the variance in earthquakes, it is essential to understand the Richter scale uses logarithms simply to make the measurements manageable (i.e., a magnitude 3 quake factors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface is underlain by permafrost, with the total area of around 18 million km2. This includes substantial areas of Alaska, Greenland, Canada and Siberia. It can also be located on mountaintops in the Southern Hemisphere and beneath ice-free areas in the Antarctic. Permafrost does not have to be the first layer that is on the ground. It can be from an inch to several miles deep under the Earth's surface. It frequently occurs in ground ice, but it can also be present in non-porous bedrock. Permafrost is formed from ice holding various types of soil, sand, and rock in combination. Permafrost contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide, making tundra soil a carbon sink. As global war ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ray Mountains
The Ray Mountains is a mountain range in central Alaska named for the Ray River, itself named for United States Army Captain Patrick Henry Ray, who established a meteorological station in Barrow, Alaska, in 1881.Donald J. Orth. Dictionary of Alaska Place Names' Washington, D.C.: U.S. Government Printing Office, 1967, p. 795. The mountains are within the Yukon-Tanana Uplands, an area of low mountain ranges that also includes the White Mountains. The Ray Mountains cover an area of and are bordered on the east by the Yukon River, on the south by the Tozitna River, and on the north by Kanuti National Wildlife Refuge Kanuti National Wildlife Refuge is a national wildlife refuge in central Alaska, United States. One of 16 refuges in Alaska, it was established in 1980 when Congress passed The Alaska National Interest Lands Conservation Act (ANILCA). At , Kanut .... The highest point in the Ray Mountains is Mount Tozi, which has a summit elevation of . Other notable peaks include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Above Sea Level
Height above mean sea level is a measure of the vertical distance (height, elevation or altitude) of a location in reference to a historic mean sea level taken as a vertical datum. In geodesy, it is formalized as ''orthometric heights''. The combination of unit of measurement and the physical quantity (height) is called "metres above mean sea level" in the metric system, while in United States customary and imperial units it would be called "feet above mean sea level". Mean sea levels are affected by climate change and other factors and change over time. For this and other reasons, recorded measurements of elevation above sea level at a reference time in history might differ from the actual elevation of a given location over sea level at a given moment. Uses Metres above sea level is the standard measurement of the elevation or altitude of: * Geographic locations such as towns, mountains and other landmarks. * The top of buildings and other structures. * Flying objects such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bering Sea
The Bering Sea (, ; rus, Бе́рингово мо́ре, r=Béringovo móre) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasses on Earth: Eurasia and The Americas. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelf, continental shelves. The Bering Sea is named for Vitus Bering, a Denmark, Danish navigator in Russian service, who, in 1728, was the first European to systematically explore it, sailing from the Pacific Ocean northward to the Arctic Ocean. The Bering Sea is separated from the Gulf of Alaska by the Alaska Peninsula. It covers over and is bordered on the east and northeast by Alaska, on the west by the Russian Far East and the Kamchatka Peninsula, on the south by the Alaska Peninsula and the Aleutian Islands and on the far north by the Bering Strait, which connects the Bering Sea to the Arctic Ocean's Chukchi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norton Sound
Norton Sound (russian: Нортон-Саунд) is an inlet of the Bering Sea on the western coast of the U.S. state of Alaska, south of the Seward Peninsula. It is about 240 km (150 mi) long and 200 km (125 mi) wide. The Yukon River delta forms a portion of the south shore and water from the Yukon influences this body of water. It is ice-free from June to October. Norton Sound was explored by Captain James Cook in September 1778. He named the body of water after Sir Fletcher Norton, then Speaker of the British House of Commons. The Norton Sound area has been home to Yup'ik and Inupiat for many centuries. It is the boundary between the two peoples; the Inupiat live to the north and the Yup'ik to the south. The town of Nome is along the northern edge of Norton Sound. The villages of Elim, Golovin, Stebbins, White Mountain, Koyuk, Shaktoolik, St. Michael, and Unalakleet are on the shores or waterways flowing into Norton Sound. The Iditarod Trail Sled Do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koyukuk River
The Koyukuk River (; ''Ooghekuhno' '' in Koyukon, ''Kuuyukaq'' or ''Tagraġvik'' in Iñupiaq) is a tributary of the Yukon River, in the U.S. state of Alaska. It is the last major tributary entering the Yukon before the larger river empties into the Bering Sea. Rising at the confluence of the North Fork Koyukuk River with the Middle Fork Koyukuk River, it flows generally southwest to meet the larger Yukon River at Koyukuk. The river, with headwaters above the Arctic Circle in the Endicott Mountains of the Brooks Range, drains an area north of the Yukon River that includes part of the Gates of the Arctic National Park and Preserve, as well as Kanuti National Wildlife Refuge and Koyukuk National Wildlife Refuge. The main stem of the river is lined by the communities of Evansville, Bettles, Alatna, Allakaket, Hughes, and Huslia before reaching Koyukuk. Its headwaters tributaries include the Koyukuk's south, middle, and north forks, the Alatna River, and the John River.Benke an ... [...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 riv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
