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Lake Breakout
Lake breakout is the collapse of a lake, usually of high-altitude. High-altitude lakes tend to form in volcanic craters – where they are called crater lakes – or in valleys dammed as the result of earthquakes or glacial or volcanic deposition. Lake breakouts are most common a few weeks or months after a volcanic eruption as a river becomes blocked by volcanic debris. Process The walls of such lakes can be unstable and may be breached after fresh earthquakes or because of erosion. As water rushes outwards, the initial channel is cut wider and deeper, further increasing the flow. This may cause the lake's rim to collapse abruptly. The usual result is for huge amounts of water to be displaced, incorporating a great deal of sediment which increases it in volume by as much as two or four times, or even more. This produces violent floods and lahars with devastating effects for any settlements in their path. Historical events The larger a temporary lake is, the more extreme th ... [...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] |
Red Rock Pass
Red Rock Pass is a low mountain pass in the western United States in southeastern Idaho, located in southern Bannock County, south of Downey. It is geologically significant as the spillway of ancient Lake Bonneville. It is traversed by U.S. Route 91 at an elevation of above sea level, bounded by two mountain ranges; the Portneuf to the east and the Bannock to the west. The pass was cut through resistant Paleozoic shale, limestone, and dolomite, and forms a narrow gap in length. At one time the pass was higher, where the shoreline of Pleistocene Lake Bonneville stood. The pass takes its name from the red limestone cliffs which border it. Red Rock Pass has a surface deposit of calcareous silty alluvium with topsoil of dark grayish brown silt loam. Bonneville flood It is believed that during the last ice age lava flows in the vicinity of Pocatello began to divert the Bear River through Lake Thatcher and then into Lake Bonneville. This sudden influx caused Bonneville ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flood
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding, for example land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees, and larger environmental issues such as climate change and sea level rise. In particular climate change's increased rainfall and extreme weather events increases the severity of other causes for flooding, resulting in more intense floods and increased flood risk. Flooding may occur as an overflow of water from water bodies, such as a river, lake, or ocean, in which the water overtops or breaks levees, resulting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Debris Dam
A landslide dam or barrier lake is the natural damming of a river by some kind of landslide, such as a debris flow, rock avalanche or volcanic eruption. If the damming landslide is caused by an earthquake, it may also be called a quake lake. Some landslide dams are as high as the largest existing artificial dam.Robert B. Jansen (1988) "Advanced Dam Engineering for Design, Construction, and Rehabilitation", Causes The major causes for landslide dams investigated by 1986 are landslides from excessive precipitation and earthquakes, which account for 84%. Volcanic eruptions account for a further 7% of dams. Other causes of landslides account for the remaining 9%. Consequences The water impounded by a landslide dam may create a dam reservoir (lake) that may last for a short time, to several thousand years. Because of their rather loose nature and absence of controlled spillway, landslide dams frequently fail catastrophically and lead to downstream flooding, often with high casualtie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Army Corps Of Engineers
, colors = , anniversaries = 16 June (Organization Day) , battles = , battles_label = Wars , website = , commander1 = LTG Scott A. Spellmon , commander1_label = Chief of Engineers and Commanding General of the U.S. Army Corps of Engineers , commander2 = MGbr>Richard J. Heitkamp, commander2_label = Deputy Chief of Engineers and Deputy Commanding General , commander3 = MGKimberly M. Colloton, commander3_label = Deputy Commanding General for Military and International Operations , commander4 = MGbr>William H. Graham, commander4_label = Deputy Commanding General for Civil and Emergency Operations , commander5 = COLbr>James J. Handura, commander5_label = Chief of Staff for the U.S. Army Corps of Engi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1980 Eruption Of Mount St
__NOTOC__ Year 198 (CXCVIII) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Sergius and Gallus (or, less frequently, year 951 ''Ab urbe condita''). The denomination 198 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire *January 28 **Publius Septimius Geta, son of Septimius Severus, receives the title of Caesar. **Caracalla, son of Septimius Severus, is given the title of Augustus. China *Winter – Battle of Xiapi: The allied armies led by Cao Cao and Liu Bei defeat Lü Bu; afterward Cao Cao has him executed. By topic Religion * Marcus I succeeds Olympianus as Patriarch of Constantinople (until 211). Births * Lu Kai (or Jingfeng), Chinese official and general (d. 269) * Quan Cong, Chinese general and advisor (d. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terrestrial planet with a thin atmosphere (less than 1% that of Earth's), and has a crust primarily composed of elements similar to Earth's crust, as well as a core made of iron and nickel. Mars has surface features such as impact craters, valleys, dunes and polar ice caps. It has two small and irregularly shaped moons, Phobos (moon), Phobos and Deimos (moon), Deimos. Some of the most notable surface features on Mars include Olympus Mons, the largest volcano and List of tallest mountains in the Solar System, highest known mountain in the Solar System and Valles Marineris, one of the largest canyons in the Solar System. The North Polar Basin (Mars), Borealis basin in the Northern Hemisphere covers approximately 40% of the planet and may be a la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canyon
A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tendency to cut through underlying surfaces, eventually wearing away rock layers as sediments are removed downstream. A river bed will gradually reach a baseline elevation, which is the same elevation as the body of water into which the river drains. The processes of weathering and erosion will form canyons when the river's River source, headwaters and estuary are at significantly different elevations, particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering. A canyon may also refer to a rift between two mountain peaks, such as those in ranges including the Rocky Mountains, the Alps, the Himalayas or the Andes. Usually, a river or stream carves out such splits between mountains. Examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington (state)
Washington (), officially the State of Washington, is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington Territory, which was ceded by the British Empire in 1846, by the Oregon Treaty in the settlement of the Oregon boundary dispute. The state is bordered on the west by the Pacific Ocean, Oregon to the south, Idaho to the east, and the Canadian province of British Columbia to the north. It was admitted to the Union as the 42nd state in 1889. Olympia is the state capital; the state's largest city is Seattle. Washington is often referred to as Washington state to distinguish it from the nation's capital, Washington, D.C. Washington is the 18th-largest state, with an area of , and the 13th-most populous state, with more than 7.7 million people. The majority of Washington's residents live in the Seattle metropolitan area, the center of trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missoula Floods
The Missoula floods (also known as the Spokane floods or the Bretz floods or Bretz's floods) were cataclysmic glacial lake outburst floods that swept periodically across eastern Washington and down the Columbia River Gorge at the end of the last ice age. These floods were the result of periodic sudden ruptures of the ice dam on the Clark Fork River that created Glacial Lake Missoula. After each ice dam rupture, the waters of the lake would rush down the Clark Fork and the Columbia River, flooding much of eastern Washington and the Willamette Valley in western Oregon. After the lake drained, the ice would reform, creating Glacial Lake Missoula again. These floods have been researched since the 1920s. During the last deglaciation that followed the end of the Last Glacial Maximum, geologists estimate that a cycle of flooding and reformation of the lake lasted an average of 55 years and that the floods occurred several times over the 2,000-year period between 15,000 and 13,000 year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Lake Missoula
Lake Missoula was a prehistoric proglacial lake in western Montana that existed periodically at the end of the last ice age between 15,000 and 13,000 years ago. The lake measured about and contained about of water, half the volume of Lake Michigan. The ''Glacial Lake Missoula National Natural Landmark'' is located about 110 kilometres (68 mi) northwest of Missoula, Montana, at the north end of the Camas Prairie Valley, just east of Montana Highway 382 and Macfarlane Ranch. It was designated as a National Natural Landmark in 1966 because it contains the great ripples (often measuring high and long) that served as a strong supporting element for J Harlen Bretz's contention that Washington State's Channeled Scablands were formed by repeated cataclysmic floods over only about 2,000 years, rather than through the millions of years of erosion that had been previously assumed. The lake was the result of an ice dam on the Clark Fork caused by the southern encroachment of a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snake River
The Snake River is a major river of the greater Pacific Northwest region in the United States. At long, it is the largest tributary of the Columbia River, in turn, the largest North American river that empties into the Pacific Ocean. The Snake River rises in western Wyoming, then flows through the Snake River Plain of southern Idaho, the rugged Hells Canyon on the Oregon–Idaho border and the rolling Palouse Hills of Washington (state), Washington, emptying into the Columbia River at the Tri-Cities, Washington, Tri-Cities in the Columbia Basin of Eastern Washington. The Snake River drainage basin encompasses parts of six U.S. states (Idaho, Washington, Oregon, Utah, Nevada, and Wyoming) and is known for its varied geologic history. The Snake River Plain was created by a volcanic hotspot (geology), hotspot which now lies underneath the Snake River headwaters in Yellowstone National Park. Gigantic glacial-retreat flooding episodes during the previous Last glacial period, Ice Ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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