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Earth Shakes, Rattles, and Rolls. Plate Tectonics Volcanoes Earthquakes. What is the relationship between the earth’s plates, volcanoes, and earthquakes?. Plates. http://www.extremescience.com/PlateTectonicsmap.htm. Earthquakes. Volcanoes. http://hsv.com/scitech/earthsci/quake.htm.
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Earth Shakes, Rattles, and Rolls Plate Tectonics Volcanoes Earthquakes
What is the relationship between the earth’s plates, volcanoes, and earthquakes?
Plates http://www.extremescience.com/PlateTectonicsmap.htm
Volcanoes http://hsv.com/scitech/earthsci/quake.htm
Plates Volcanoes Earthquakes
Earthquakes and Volcanoes are found where plates meet.
Evidence Wegener used to support theory of continental drift: • Continents fit like a puzzle • Fossil evidence • Rocks were similar in Africa and South America • Evidence Antarctica once had a tropical climate
How did geologists explain how the earth’s plates moved? Continental Drift Mid-Atlantic Ridge allows mantle to seep to surface through cracks and pushes plates of the earth apart.
To see how geologists believe the plates moved go to the site below. Notice the Atlantic Ocean seafloor spreading. Seafloor spreading animation
Layers of the Earth • Crust • Mantle • Outer core • Inner core
VOLCANIC MOUNTAIN NAMIBIA IN AFRICA
Volcanic mountains • Formed when molten rock, or magma deep within the earth, erupts, and piles upon the surface • Takes place where two of the earth's tectonic plates collide.
Convection currents in the Earth's mantle are what drive plate motions. Convection currents are driven by the simple fact that hot things (such as gases and liquids) rise while cool things fall.
epicenter The point on the surface of Earth that is right above the focus of an earthquake http://www.harcourtschool.com/glossary/science/define/gr4/epicenter4c.html
Earthquakes How do we measure the intensity of an earthquake?
Seismographmeasures Magnitude or the strength of an earthquake
Richter Scale Earthquake Magnitudes Effects Less than 3.5Generally not felt 3.5-5.4Rarely causes damage. Under 6.0 Slight damage to well-designed buildings. 6.1-6.9 Destructive to about 100 kilometers across 7.0-7.9 Major earthquake. Serious damage over larger areas. 8 or greater Great earthquake.
Richter Magnitude Number of Earthquakes per year 1.0 to 3.9 900,000 + 4.0-4.9 6200 5.0-5.9 800 6.0-6.9 226 7.0-7.9 18 8.0-8.9 Less than 2
Earthquakes in the ocean cause Tsunamis
Tsunamis 30’ Wall of Water Destruction
Types of Volcanos • Composite • Cinder Cone • Shield
Vesuvius, Krakatoa, Fujiyama, and Mount St. Helens • tens of miles across and ten thousand or more feet in height. • have small craters in their summits http://images.google.com/imgres?imgurl=http://www.cotf.edu/ete/images/modules/volcanoes/typesb.GIF&imgrefurl=http://www.cotf.edu/ete/modules/volcanoes/vtypesvolcan1.html&h=236&w=265&sz=14&tbnid=qZF0vXnHnOkJ:&tbnh=96&tbnw=107&start=19&prev=/images%3Fq%3Dcomposite%2Bvolcano%26hl%3Den%26lr%3D%26sa%3DN
consist almost entirely of loose, grainy cinders and almost no lava • small volcanoes • steep sides and usually have a small crater on top http://images.google.com/imgres?imgurl=http://www.cotf.edu/ete/images/modules/volcanoes/typesb.GIF&imgrefurl=http://www.cotf.edu/ete/modules/volcanoes/vtypesvolcan1.html&h=236&w=265&sz=14&tbnid=qZF0vXnHnOkJ:&tbnh=96&tbnw=107&start=19&prev=/images%3Fq%3Dcomposite%2Bvolcano%26hl%3Den%26lr%3D%26sa%3DN
hundreds of miles across and many tens of thousands of feet high. • Mauna Loa • consist almost entirely of frozen lavas • large craters at their summits. http://images.google.com/imgres?imgurl=http://www.cotf.edu/ete/images/modules/volcanoes/typesb.GIF&imgrefurl=http://www.cotf.edu/ete/modules/volcanoes/vtypesvolcan1.html&h=236&w=265&sz=14&tbnid=qZF0vXnHnOkJ:&tbnh=96&tbnw=107&start=19&prev=/images%3Fq%3Dcomposite%2Bvolcano%26hl%3Den%26lr%3D%26sa%3DN
largest single mountain in the world • 30,000 +feet above the ocean floor • 100 miles across at its base.