Mount St. Helens - Wikipedia, the free encyclopedia - The Diigo Meta page

• 13 Mar 15
  

  twheeler21
  • located in Skamania County, Washington,
  • Mount St. Helens is most notorious for its catastrophic eruption on May 18, 1980, at 8:32 a.m. PDT,^[2] the deadliest and most economically destructive volcanic event in the history of the United States. Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway were destroyed. A massive debris avalanche triggered by an earthquake measuring 5.1 on the Richter scale caused an eruption that reduced the elevation of the mountain's summit from 9,677 ft (2,950 m) to 8,365 ft (2,550 m), replacing it with a 1 mile (1.6 km) wide horseshoe-shaped crater.^[3] The debris avalanche was up to 0.7 cubic miles (2.9 km³) in volume. The Mount St. Helens National Volcanic Monument was created to preserve the volcano and allow for its aftermath to be scientifically studied.
  •    Elevation 8,365 ft (2,550 m)
  • Prominence 4,605 ft (1,404 m)
  • Mount St. Helens is geologically young compared with the other major Cascade volcanoes. It formed only within the past 40,000 years, and the pre-1980 summit cone began rising about 2,200 years ago.^[4]

  • The volcano is considered the most active in the Cascades within the Holocene epoch (the last 10,000 or so years).^[5]

     
  • Prior to the 1980 eruption, Mount St. Helens was the fifth-highest peak in Washington.
  • St. Helens started its growth in the Pleistocene 37,600 years ago,

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• 28 Oct 14
  

  Marion Da Costa
  • 
• 04 Mar 14
  

  kirsten reader
  • 
• 16 Feb 14
  

  kaylawebb54
  • stratovolcano
  • The volcano is located in the Cascade Range
  • ash explosions and pyroclastic flows
  • basalt and andesite through which several domes of dacite lava have erupted.
  • formed only within the past 40,000 years
  • The peak rose more than 5,000 feet (1,500 m) above its base
  • Crater Glacier
  • 2004, the glacier lobes were pushed aside and upward by the growth of new volcanic domes
  • The surface of the glacier, once mostly without crevasses, turned into a chaotic jumble of icefalls heavily criss-crossed with crevasses and seracs caused by movement of the crater floor
  • "Ape Canyon Stage" (around 40,000–35,000 years ago), the "Cougar Stage" (ca. 20,000–18,000 years ago), and the "Swift Creek Stage" (roughly 13,000–8,000 years ago)
  • 2500 BCE, is called the "Spirit Lake Stage"
  • started its growth in the Pleistocene 37,600 years ago,

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• 12 Apr 13
  

  jenknutsen
  • 
• 20 Nov 12
  

  olivia c

  Good source for background information on Mt. St. Helens

  • Mount St. Helens is an active stratovolcano l
  • Mount St. Helens is most notorious for its catastrophic eruption on May 18, 1980
  • As with most other volcanoes in the Cascade Range, Mount St. Helens is a large eruptive cone consisting of lava rock interlayered with ash, pumice, and other deposits

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• 16 Nov 12
  

  Gillian Diebold

  Mt St Helens Volcano

  • The volcano is located in the Cascade Range and is part of the Cascade Volcanic Arc, a segment of the Pacific Ring of Fire that includes over 160 active volcanoes. This volcano is well known for its ash explosions and pyroclastic flows.

     

    Mount St. Helens is most notorious for its catastrophic eruption on May 18, 1980, at 8:32 am PDT,^[2] the deadliest and most economically destructive volcanic event in the history of the United States. Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway were destroyed. A massive debris avalanche triggered by an earthquake measuring 5.1 on the Richter scale, caused an eruption, reducing the elevation of the mountain's summit from 9,677 ft (2,950 m) to
  • 8,365 ft (2,550 m) and replacing it with a 1 mile (1.6 km) wide horseshoe-shaped crater.^[3] The debris avalanche was up to 0.7 cubic miles (2.9 km³) in volume.
  • As with most other volcanoes in the Cascade Range, Mount St. Helens is a large eruptive cone consisting of lava rock interlayered with ash, pumice, and other deposits. The mountain includes layers of basalt and andesite through which several domes of dacite lava have erupted. The largest of the dacite domes formed the previous summit, and off its northern flank sat the smaller Goat Rocks dome. Both were destroyed in the 1980 eruption.

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• 01 Feb 12
  

  John O

  volcaon project due feb 3

  mount Saint helins volcano project

• 15 Nov 11
  

  Morgan Smith
  • a second earthquake, of magnitude 5.1, triggered a massive collapse of the north  face of the mountain. It was the largest known debris avalanche in  recorded history
  • a second earthquake, of magnitude 5.1, triggered a massive collapse of the north  face of the mountain
  • The collapse of the northern flank of St. Helens mixed with ice, snow, and water  to create lahars (volcanic mudflows). The  lahars flowed many miles down the Toutle and Cowlitz Rivers, destroying bridges and lumber  camps
  • Ashes from the eruption were found collecting on top of cars and roofs next  morning, as far as the city of Edmonton in Alberta, Canada.
  • The removal of the north side of the mountain reduced St. Helens' height by  about 1,300 feet (400 m) and left a crater 1 mile (1.6 km) to 2 miles  (3.2 km) wide and 0.5 miles (800 m) deep, with its north end open in a  huge breach
  • The eruption killed 57 people, nearly 7,000 big game animals (deer, elk, and bear), and an estimated 12 million fish from a  hatchery.
  • It destroyed or extensively damaged over 200 homes, 185 miles (298 km) of  highway and 15 miles (24 km) of  railways

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• 09 Jun 11
  

  MissEmily Griffith
• 31 Mar 11
  

  Daniel Caragiulo
  • Mount St. Helens is an active stratovolcano
  • Skamania County, Washington,
  • Pacific Northwest region of the United States
  • 96 miles (154 km) south of Seattle, Washington and 50 miles (80 km) northeast of Portland, Oregon.
  • Lord St Helens
  • Cascade Range and is part of the Cascade Volcanic Arc,
  • This volcano is well known for its ash explosions and pyroclastic flows.
  • Pacific Ring of Fire
  • Mount St. Helens is most famous for its catastrophic eruption on May 18, 1980, at 8:32 am PDT
  • which was the deadliest and most economically destructive volcanic event in the history of the United States.
  • Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway we
  • re destroyed.
  • earthquake measuring 5.1 on the Richter scale, caused an eruption, reducing the elevation of the mountain's summit from 9,677 ft (2,950 m) to 8,365 ft (2,550 m) and replacing it with a 1 mile (1.6 km) wide horseshoe-shaped crater.
  • large eruptive cone consisting of lava rock interlayered with ash, pumice, and other deposits.
  • The earthquake was caused by a sudden surge of magma from the Earth's mantle.^[3]
  • Mount St. Helens National Volcanic Monument

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• 29 Nov 10
  

  elise fraser
  • nd most economically destructive volcanic event in the history of the United States. Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway we
  • Fifty-seven people were killed; 250 homes, 47 bridges, 15 miles (24 km) of railways, and 185 miles (298 km) of highway were destroyed.
  • Had the eruption occurred one day later, when loggers would have been at work, rather than on a Sunday, the death toll wo

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• 23 Nov 09
  

  Tyler Strine
  • From December 7, 1989 to January 6, 1990, and from No
  • Cascade Range, Mount St. Helens is a large eruptive cone consisting of lava
  • St. Helens catastrophically erupted on May 18, 1980. After many months of  lead-up activity, including the growth of a huge bulge on the north part of the  mountain, a moderate earthquake caused the entire north flank of the mountain to  slide away in the largest landslide in recorded history
  • The newly exposed hot and pressurized rock in the volcano responded by producing  the largest historic volcanic eruption in the 48 contiguous U.S. states.^[30] (See  the Geology section for more detail.)
  • U.S. President Jimmy Carter surveyed the  damage and said, "Someone said this area looked like a moonscape. But the moon  looks more like a golf course compared to what's up there."^[32]  A film crew, led by Seattle filmmaker Otto Seiber, was dropped by helicopter on St. Helens on May 23  to document the destruction. Their compasses, however, spun in circles and they quickly  became lost. A second eruption occurred on May 25, but the crew survived and was  rescued two days later by National Guard helicopter pilots
  • On March 20, 1980, Mount St. Helens experienced a magnitude 4.2 earthquake
  • On March 20, 1980, Mount St. Helens experienced a magnitude
  • The collapse of the northern flank of St. Helens mixed with ice, snow, and water  to create lahars (volcanic mudflows). The  lahars flowed many miles down the Toutle and Cowlitz Rivers, destroying bridges  and lumber camps. A total of 3,900,000 cubic yards  (3,000,000 m³) of material was transported 17 miles  (27 km) south into the Columbia River by the mudflows.^[43]
  • For more than nine hours, a vigorous plume of ash erupted, eventually reaching  12 to 16 miles (20 to 27 km) above sea level.^[44]  The plume moved eastward at an average speed of 60 miles per hour  (100 km/h) with ash reaching Idaho by  noon. Ashes from the eruption were found collecting on top of cars and roofs  next morning, as far as the city of Edmonton in Alberta, Canada
  • From December 7, 1989 to January 6, 1990, and from No
  • nd from

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• 14 Jan 08
  

  whiteknoll

  fifthgrade science volcano

  • <table style="CLEAR: right; BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; MARGIN-TOP: 0.75em; FONT-SIZE: 95%; BACKGROUND: #ffffff; FLOAT: right; MARGIN-BOTTOM: 0.75em; MARGIN-LEFT: 0.75em; BORDER-LEFT: #999966 1px solid; WIDTH: 305px; BORDER-BOTTOM: #999966 1px solid" class="infobox geography vcard" cellspacing="0" cellpadding="5"><br/><tbody><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3"><a rel="nofollow" href="http://en.wikipedia.org/wiki/Topographic_map" title="Topographic map">map</a></td><br/><td style="BORDER-TOP: #999966 1px solid"><a rel="nofollow" href="http://en.wikipedia.org/wiki/USGS" class="mw-redirect" title="USGS"><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="1f2d91b5698f22c1da8aedd9ceb921ef-num" class="diigo.numbering">#26</sup><br/>USGS<br/></a> <br/><br/>Mount St. <br/>Helens<br/></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3" class="note"><a rel="nofollow" href="http://en.wikipedia.org/wiki/List_of_mountain_types" title="List of mountain types"><br/>Type<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="3f164ca88f72d6df353aaa31a8d718d0-num" class="diigo.numbering"><br/>#21<br/></sup><br/><br/>Active<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.orghttp://en.wikipedia.org/wiki/Stratovolcano" title="Stratovolcano"><br/><br/>stratovolcano<br/><br/></a></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3" class="note"><br/>Volcanic<br/>&nbsp;<a rel="nofollow" href="http://en.wikipedia.org/wiki/Volcanic_arc" title="Volcanic arc"><br/>arc<br/></a><br/>/<br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Volcanic_belt" title="Volcanic belt"><br/>belt<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><a rel="nofollow" href="http://en.wikipedia.orghttp://en.wikipedia.org/wiki/Cascade_Volcanoes" title="Cascade Volcanoes"><br/>Cascade <br/>Volcanic Arc<br/></a></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3" class="note"><a rel="nofollow" href="http://en.wikipedia.org/wiki/Geologic_time_scale" title="Geologic time scale"><br/>Age of<br/> <br/><br/>rock<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><br/>&lt; <sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="0032952cf1a45ada54069a63cea0ef48-num" class="diigo.numbering">#20<br/></sup><br/><br/>40,000<br/> <br/><br/>yrs<br/><br/></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3" class="note"><a rel="nofollow" href="http://en.wikipedia.orghttp://en.wikipedia.org/wiki/Volcano" title="Volcano"><br/>Last <br/>eruption<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="5503f08b2bd52268e8010b90354c3c61-num" class="diigo.numbering"><br/>#19<br/></sup><br/><br/>2004–2008<br/> <br/><br/>(ongoing)<br/><br/></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3" class="note"><a rel="nofollow" href="http://en.wikipedia.org/wiki/First_ascent" title="First ascent"><br/>First <br/>ascent<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="3ab523d4145f41687b96398b71ce1894-num" class="diigo.numbering"><br/>#18<br/></sup><br/><br/>1853 <br/>by<br/><br/> <a rel="nofollow" href="http://en.wikipedia.org/wiki/Thomas_J._Dryer" title="Thomas J. Dryer"><br/><br/>Thomas<br/> <br/><br/>J.<br/><br/> <br/><br/><br/>Dryer<br/><br/></a></td></tr><br/><tr><br/><td style="BORDER-RIGHT: #999966 1px solid; BORDER-TOP: #999966 1px solid; BACKGROUND: #e7dcc3"><br/>Easiest<br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Climbing_route" title="Climbing route"><br/>route<br/></a></td><br/><td style="BORDER-TOP: #999966 1px solid"><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="4f5d8a91d87fc098e252b7d058ebce70-num" class="diigo.numbering"><br/>#17<br/></sup><br/><br/>Hike via <br/>south<br/> <br/>slope of <br/>volcano (closest area near eruption<br/> <br/>site)<br/><br/></td></tr></tbody></table><br/><p><b><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="79d23c09a9a236c14543cb1a3d57ee77-num" class="diigo.numbering"><br/>#1<br/></sup><br/><br/>Mount <br/>St.<br/> <br/>Helens<br/><br/></b> <br/><br/><br/>is an<br/> <br/><br/>active<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Stratovolcano" title="Stratovolcano"><br/><br/>stratovolcano<br/><br/></a> <br/><br/><br/>located<br/> <br/><br/>in<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Skamania_County%2C_Washington" title="Skamania County, Washington"><br/><br/>Skamania<br/> <br/><br/>County<br/><br/></a><br/><br/>,<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Washington" title="Washington"><br/><br/>Washington<br/><br/></a><br/><br/>, in<br/> <br/><br/>the<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Pacific_Northwest" title="Pacific Northwest"><br/><br/>Pacific<br/> <br/><br/>Northwest<br/><br/></a> <br/><br/><br/>region <br/>of<br/> <br/>the<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/United_States" title="United States"><br/><br/>United<br/><br/> <br/><br/><br/>States<br/><br/></a><br/>.<br/> <sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="be8dfca0bf82e0c45de14133fb51fb48-num" class="diigo.numbering"><br/>#2<br/></sup><br/><br/>It is 96 <br/>miles<br/> <br/>(154<br/><br/>&nbsp;<br/><br/>km) <br/>south<br/> <br/>of<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Seattle%2C_Washington" title="Seattle, Washington"><br/><br/>Seattle<br/><br/></a> <br/><br/><br/>and 53 <br/>miles<br/> <br/>(85<br/><br/>&nbsp;<br/><br/>km)<br/><br/> <br/><br/><br/>northeast<br/> <br/><br/>of<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Portland%2C_Oregon" title="Portland, Oregon"><br/><br/>Portland,<br/> <br/><br/>Oregon<br/><br/></a><br/><br/>.<br/><br/> <br/><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="8980aa5eacc7ed4fc8c3c0470383b479-num" class="diigo.numbering"><br/>#12<br/></sup><br/><br/>Mount <br/>St.<br/> <br/>Helens takes <br/>its<br/><br/> <a rel="nofollow" href="http://en.wikipedia.org/wiki/English_language" title="English language"><br/><br/>English<br/><br/></a> <br/><br/><br/>name <br/>from<br/> <br/>the<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/United_Kingdom" title="United Kingdom"><br/><br/>British<br/><br/></a> <br/><br/><br/>diplomat<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Alleyne_Fitzherbert%2C_1st_Baron_St_Helens" class="mw-redirect" title="Alleyne Fitzherbert, 1st Baron St Helens"><br/><br/>Lord St<br/> <br/><br/>Helens<br/><br/></a><br/><br/>, <br/>a<br/><br/> <br/><br/>friend <br/>of<br/> <br/>explorer<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/George_Vancouver" title="George Vancouver"><br/><br/>George<br/> <br/><br/>Vancouver<br/><br/></a> <br/><br/><br/>who made <br/>a<br/> <br/>survey of the <br/>area<br/><br/> <br/><br/>in the <br/>late<br/> <br/>18th <br/>century.<br/><br/> <sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="ce5bace39186f9e8e4b785513ecad487-num" class="diigo.numbering"><br/>#3<br/></sup><br/><br/>The mountain <br/>is<br/> <br/>located in <br/>the<br/><br/> <a rel="nofollow" href="http://en.wikipedia.org/wiki/Cascade_Range" title="Cascade Range"><br/><br/>Cascade<br/> <br/><br/>Range<br/><br/></a> <br/><br/><br/>and is part <br/>of<br/> <br/>the<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Cascade_Volcanoes" title="Cascade Volcanoes"><br/><br/>Cascade<br/> <br/><br/>Volcanic<br/><br/> <br/><br/><br/>Arc<br/><br/></a><br/><br/>, a segment <br/>of<br/> <br/>the<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Pacific_Ring_of_Fire" title="Pacific Ring of Fire"><br/><br/>Pacific Ring <br/>of<br/> <br/>Fire<br/><br/></a> <br/><br/><br/>that <br/>includes<br/> <br/>over<br/><br/> <br/><br/><br/>160<br/> <br/><br/>active<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Volcano" title="Volcano"><br/><br/>volcanoes<br/><br/></a><br/><br/>.<br/><br/> <br/><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="226c0be25ea1f1eee361e2f32780c41e-num" class="diigo.numbering"><br/>#10<br/></sup><br/><br/>This volcano <br/>is<br/> <br/>well known for <br/>its<br/><br/> <a rel="nofollow" href="http://en.wikipedia.org/wiki/Volcanic_ash" title="Volcanic ash"><br/><br/>ash<br/><br/></a> <br/><br/><br/>explosions<br/> <br/><br/>and<br/><br/> <br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Pyroclastic_flow" title="Pyroclastic flow"><br/><br/>pyroclastic<br/> <br/><br/>flows<br/><br/></a><br/><br/>.<br/><br/></p><br/><p><sup name="diigo.numbering" style="DISPLAY: inline; CURSOR: pointer; FONT-FAMILY: 'lucida grande',tahoma,verdana,arial,sans-serif! important; BACKGROUND-COLOR: #ffff99" id="4588f5a00a2e8cc72fccd21ab6fd68a2-num" class="diigo.numbering"><br/>#4<br/></sup><br/><br/>Mount <br/>St.<br/> <br/>Helens is most <br/>famous for<br/><br/> <a rel="nofollow" href="http://en.wikipedia.org/wiki/1980_eruption_of_Mount_St._Helens" title="1980 eruption of Mount St. Helens"><br/><br/>its<br/> <br/><br/></a></p>
  • USGS Mount St. Helens
  • field,

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