|
Glacier Peak
Glacier Peak or Dakobed (known in the Sauk-Suiattle dialect of the Lushootseed language as "Tda-ko-buh-ba" or "Takobia") is the most isolated of the five major stratovolcanoes (composite volcanoes) of the Cascade Volcanoes, Cascade Volcanic Arc in the United States, U.S state of Washington (state), Washington. Located in the Glacier Peak Wilderness in Mount Baker–Snoqualmie National Forest, the volcano is visible from the west in Seattle, and from the north in the higher areas of eastern suburbs of Vancouver such as Coquitlam, New Westminster and Port Coquitlam. The volcano is the fourth tallest peak in Washington state, and not as much is known about it compared to other volcanoes in the area. Local Native Americans in the United States, Native Americans have recognized Glacier Peak and other Washington volcanoes in their histories and stories. When American explorers reached the region, they learned basic information about surrounding landforms, but did not initially understa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of The Most Prominent Summits Of North America
The following sortable tables comprise the Topographic prominence, most topographically prominent Summit, mountain peaks of North America, greater North America. Each of these 353 summits has at least of topographic prominence. This article defines greater North America as the portion of the continental landmass of the Americas extending westward and northward from the Isthmus of Panama plus the islands surrounding that landmass. This article defines the islands of North America to include the coastal islands of North America, the islands of the Caribbean Sea, the Lucayan Archipelago, the Bermuda Islands, the Islands of Greenland (Kalaallit Nunaat), the islands of Northern Canada, the islands of Alaska, and the islands of the northeastern Pacific Ocean. The Hawaiian Islands are not included because they are considered part of Oceania. With the exceptions of North Carolina's Mount Mitchell and New Hampshire's Mount Washington, all of the ultras in the United States are found w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Native Americans In The United States
Native Americans (also called American Indians, First Americans, or Indigenous Americans) are the Indigenous peoples of the Americas, Indigenous peoples of the United States, particularly of the Contiguous United States, lower 48 states and Alaska. They may also include any Americans whose origins lie in any of the indigenous peoples of North or South America. The United States Census Bureau publishes data about "American Indians and Alaska Natives", whom it defines as anyone "having origins in any of the original peoples of North and South America ... and who maintains tribal affiliation or community attachment". The census does not, however, enumerate "Native Americans" as such, noting that the latter term can encompass a broader set of groups, e.g. Native Hawaiians, which it tabulates separately. The European colonization of the Americas from 1492 resulted in a Population history of Indigenous peoples of the Americas, precipitous decline in the size of the Native American ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Spring
A hot spring, hydrothermal spring, or geothermal spring is a Spring (hydrology), spring produced by the emergence of Geothermal activity, geothermally heated groundwater onto the surface of the Earth. The groundwater is heated either by shallow bodies of magma (molten rock) or by circulation through fault (geology), faults to hot rock deep in the Earth's crust. Hot spring water often contains large amounts of dissolved minerals. The chemistry of hot springs ranges from acid sulfate springs with a pH as low as 0.8, to alkaline chloride springs saturated with silica, to bicarbonate springs saturated with carbon dioxide and carbonate minerals. Some springs also contain abundant dissolved iron. The minerals brought to the surface in hot springs often feed communities of extremophiles, microorganisms adapted to extreme conditions, and it is possible that life on Earth had its origin in hot springs. Humans have made use of hot springs for bathing, relaxation, or medical therapy for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dishpan Gap
Dishpan Gap is a cinder cone in Chelan County of Washington, US. Located near Glacier Peak and White Chuck Cinder Cone, its elevation is approximately . Known for his creative naming of natural features in the Cascade Range, forest supervisor Albert Hale Sylvester Albert Hale Sylvester (May 25, 1871 – September 14, 1944) was a pioneer surveyor, explorer, and forest supervisor in the Cascade Range of the U.S. state of Washington. He was a topographer for the United States Geological Survey (USGS) in the ... named Dishpan Gap for the presence of an "old rusty dishpan discarded by some previous camper". References Geography of Washington (state) Cinder cones of the United States Cascade Volcanoes Volcanoes of Washington (state) {{ChelanCountyWA-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Chuck Cinder Cone
White Chuck Cinder Cone is a cinder cone near Glacier Peak in Snohomish County of Washington, USA. Located near the headwaters of the White Chuck River, its existence was first reported by Everett Houghland in 1934. Its elevation is . Based on the amount of glacial erosion on the cinder cone, it is probably between 2,000 and 17,000 years old. Geology The North Cascades feature some of the most rugged topography in the Cascade Range with craggy peaks, spires, ridges, and deep glacial valleys. Geological events occurring many years ago created the diverse topography and drastic elevation changes over the Cascade Range leading to the various climate differences. The history of the formation of the Cascade Mountains dates back millions of years ago to the late Eocene Epoch. With the North American Plate overriding the Pacific Plate, episodes of volcanic igneous activity persisted. Glacier Peak, a stratovolcano that is north-northeast of White Chuck Cinder Cone, began forming i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinder Cone
A cinder cone or scoria cone is a steep, volcanic cone, conical landform of loose pyroclastic rock, pyroclastic fragments, such as volcanic ash, clinkers, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that is often symmetrical, with slopes between 30° and 40° and a nearly circular base. Most cinder cones have a bowl-shaped volcanic crater, crater at the summit. Mechanics of eruption Cinder cones range in size from tens to hundreds of meters tall. They are composed of loose pyroclastic material (Scoria, cinder or scoria), which distinguishes them from ''spatter cones'', which are composed of agglomerated volcanic bombs. The pyroclastic material making up a cinder cone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tephra
Tephra is fragmental material produced by a Volcano, volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, they remain as tephra unless hot enough to fuse into pyroclastic rock or tuff. When a volcano explodes, it releases a variety of tephra including ash, cinders, and blocks. These layers settle on the land and, over time, sedimentation occurs incorporating these tephra layers into the geologic record. Tephrochronology is a geochronological technique that uses discrete layers of tephra—volcanic ash from a single eruption—to create a chronological framework in which Paleoecology, paleoenvironmental or Archaeology, archaeological records can be placed. Often, when a volcano explodes, biological organisms are killed and their remains are buried within the tephra layer. These fossils are later dated by scientists to determine the age of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauk River (Washington)
The Sauk River is a tributary of the Skagit River, approximately long, in northwestern Washington in the United States. It drains an area of the high Cascade Range in the watershed of Puget Sound north of Seattle. The river is a popular destination for fly fishing. It is a National Wild and Scenic River. Its two forks rise in the Cascades in eastern Snohomish County, in the Glacier Peak Wilderness and join to form the mainstem Sauk River at Bedal Peak. From there the river flows northwest from there through a remote section of the Mount Baker-Snoqualmie National Forest to Darrington, then north to join the Skagit River from the south at Rockport. The Sauk River receives the Suiattle River from the east approximately south of Rockport and the White Chuck River just above Darrington. Another important tributary is Clear Creek, which joins the Sauk just above Darrington. At Darrington the Sauk River comes so close to the head of the North Fork Stillaguamish River that boats ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dacite
Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. It is composed predominantly of plagioclase feldspar and quartz. Dacite is relatively common, occurring in many tectonic settings. It is associated with andesite and rhyolite as part of the subalkaline tholeiitic and calc-alkaline magma series. Etymology The word ''dacite'' comes from Dacia, a province of the Roman Empire which lay between the Danube River and Carpathian Mountains (now modern Romania and Moldova) where the rock was first described. The term ''dacite'' was used for the first time in the scientific literature in the book ''Geologie Siebenbürgens'' (''The Geology of Transylvania'') by Austrian geologists Franz Ritter von Hauer and Guido Stache. Dacite was originally defined as a new rock type to separate calc-alkaline ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornblende
Hornblende is a complex silicate minerals#Inosilicates, inosilicate series of minerals. It is not a recognized mineral in its own right, but the name is used as a general or field term, to refer to a dark amphibole. Hornblende minerals are common in Igneous rock, igneous and metamorphic rocks. The general formula is . Physical properties Hornblende has a Mohs scale of mineral hardness, hardness of 5–6, a specific gravity of 3.0 to 3.6, and is typically an opaque green, dark green, brown, or black color. It tends to form slender prismatic to bladed crystals, diamond-shaped in cross section, or is present as irregular grains or fibrous masses. Its planes of cleavage (crystal), cleavage intersect at 56° and 124° angles. Hornblende is most often confused with the pyroxene series and biotite, biotite mica, which are also dark minerals found in granite and charnockite. Pyroxenes differ in their cleavage planes, which intersect at 87° and 93°. Hornblende is an inosilicate (cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lahar
A lahar (, from ) is a violent type of mudflow or debris flow composed of a slurry of Pyroclastic rock, pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a valley, river valley. Lahars are often extremely destructive and deadly; 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 in the Philippines and Nevado del Ruiz in Colombia, the latter of which killed more than 20,000 people in the Armero tragedy. Etymology The word ''lahar'' is of Javanese language, 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%), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic 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 deadliest 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 that 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 Frenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
