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Hot Spot Volcanoes Animation Animation 2

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Hot Spot Volcanoes. Animation Animation 2. Volcanic activity at mid-ocean ridge can form ocean islands ( e.g ., Iceland). Volcanic Activity at Tectonic Plate Boundaries. Source: USGS http://pubs.usgs.gov/gip/hawaii/page10.html. However Not all volcanoes occur at plate boundaries. - PowerPoint PPT Presentation

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  • Hot Spot VolcanoesAnimationAnimation 2

  • Volcanic activity at mid-ocean ridge can form ocean islands (e.g., Iceland).

  • Volcanic Activity at Tectonic Plate BoundariesSource: USGS http://pubs.usgs.gov/gip/hawaii/page10.html

  • However Not all volcanoes occur at plate boundaries.HOT SPOTS: areas of volcanoes that result from plumes of hot solid material that have risen from deep within Earths mantle.

  • Map of hot spotshttp://www.math.montana.edu/~nmp/materials/ess/geosphere/advanced/activities/hotspots/index.html

  • Hawaiian IslandsSource: USGS http://pubs.usgs.gov/gip/hawaii/page05.html

  • Northwest Movement of Pacific Plate Over Fixed Hawaiian Hot SpotSource: USGS http://pubs.usgs.gov/gip/hawaii/page12.html

  • Ages of Hawaiian IslandsSource: http://volcano.und.edu/vwdocs/vwlessons/hotspots.html

  • Hot Spot VolcanismAll of the mountains in this map of the floor of the Pacific Ocean are volcanoesNote that there are several long chains of volcanoesBut there are also many individual volcanoesNone of these volcanoes are formed along plate boundaries

  • Hot Spot VolcanismThese isolated areas of volcanic activity are not associated with plate boundariesThese volcanoes are found both on continents and out in the ocean

  • Hot Spot VolcanismA plume of hot mantle material rises up to the bottom of the lithosphere Melting occurs and magma is createdThese are called hot spotsThey can last for many millions of years

  • Hot Spot VolcanismThe magma works its way to the surface over the hot spot and a volcano is formedOut in the ocean, the volcano may or may not reach the surface and form an islandIn fact, few oceanic volcanoes reach the surface

  • Hot Spot VolcanismAs the moving plate carries the volcano away from the hot spot, the volcano dies outWith time, another volcano may form This cycle may repeat many times, forming a long chain of under sea volcanoes and islands

  • The Hawaiian Islands are the classic example of hot spot volcanismHot Spot Volcanism

  • Hot Spot VolcanismEvery island in the Hawaiian Island chain was created by volcanic eruptions that occurred as the Pacific Oceanic Plate crossed over a hot spot

  • Hot Spot VolcanismIn fact, the 7 main Hawaiian Islands are just the southern most portion of two great undersea mountain ranges, composed of hundreds of volcanoes, that runs for 6000 kilometers (4000 miles) across the floor of the Pacific Ocean

  • Hot Spot VolcanismThe plate has moved to the northwest for more than 65 million yearsThe big island of Hawaii is now over the hot spot

  • The volcanoes that formed the Hawaiian islands are classified as shield volcanoesHot Spot Volcanism

  • Hot Spot VolcanismShield volcanoes are characterized by broad, gentle slopes built up from repeated basaltic lava flows

  • Hot Spot VolcanismNot all eruption create big islandsMolokini represents one eruption that is slowly being reclaimed by the sea

  • Hot Spot VolcanismLoihi Volcano, the youngest volcano of the Hawaiian Island Chain, lies about 20 km off the south coast of the Big IslandCurrently it rises 3500 meters above the surrounding sea floor and its summit is about 1000 meters beneath the surface

  • Fast and Slow Changes to Earths Surfacehttp://www.pbs.org/wgbh/aso/tryit/tectonics/shockwave-nojs.html Changes due to Plate TectonicsFast: Earthquakes and volcanoesSlow: Continental Drift

  • Fast Process: Volcanoes and Hot Spotshttp://www.youtube.com/watch?v=tfXGbzgGJ74 bill nye 8 minSilly bill: