Inner core Mantle Outer core Crust Protoplanet Protoplanet hypothesis Asthenosphere Collision boundary Convergent boundary Diverging boundary Subduction Fault Craton Lithosphere Plate tectonics Spreading centers Mohorivic Discontinuity “Moho” Unit 3: Plate Tectonics Vocab

Earths origin and structure. Origin Hypothesis The origin of the solar system has to consider the following six facts. 1.All planets move around the sun in the same direction. 2.The paths, or obits, of the planets around the sun are elliptical. 3.Most of the orbits are in nearly the same flat surface. (Plain)

Origin Hypothesis 4.The sun turns on its axis in almost the same plain as the planets and in the same direction that the planets revolve. 5.Most of the planets rotate in the same direction as the sun. 6.Seven of the nine planets have moons. Most of the moons revolve around the planets in the same direction that the planets revolve around the sun.

Protoplanet Hypothesis Protoplanet hypothesis The protoplanet hypothesis suggests that 5 billion years ago a great ball of gas and dust rotated slowly in space. It ranged at least 10 billion KM in diameter. As time passed it shrank under the pull of its own gravity. Most of the cloud’s material gathered around its own center. Its shrinking made it rotate faster. The compression of its material made its interior so hot that a powerful reaction, hydrogen fusion, began and the core of the cloud blazed into a newborn sun.

Origin of the oceans When the earth was created it had neither atmosphere nor oceans. There were three sources of heat in the protoplanet Earth. (compression, radioactive materials, and meteor showers) The heat built up and volcanic eruptions began. The eruptions produced volcanic gases. The steam in these gases condensed upon reaching the surface to form the earth’s oceans.

Origin of the atmosphere The atmosphere that surrounds Earth today includes about 78% free nitrogen and 21% free oxygen. Free means gases are not combined with any other elements. The remaining other percent is made up of argon, carbon dioxide, and helium. Free oxygen came from the breakup of water molecules by sunlight into the upper atmosphere. Green plants added more oxygen to the atmosphere by photosynthesis.

Structure of the Solid Earth Crust: 10Km Thick at ocean basin, 65Km at mountain top Mantle: 2900KM thick Outer Core: 2250K m thick Inner Core: 1200K m thick ? What Causes the layers??? A. Density Differences, B. Temperature differences. C. Materials

1. Crust: solid rock, includes dry and wet land. 2. Mantle: hot & solid rock a. Lithosphere: Upper, rigid part of the mantle 1.) Moho: boundary between the crust & mantle b. Asthenosphere: upper most portion of mantle, semi liquid layer

3. Core: made up of mostly metals, very hot! a. outer core: liquid metal b. inner core: solid, dense metal

Seismic waves Waves travel at different speeds through liquids & solids. (Also different types of minerals) discoveries/videos/100- greatest-discoveries- the-core-of-the- earth.htmhttp://science.discovery.com/tv-shows/greatest- discoveries/videos/100- greatest-discoveries- the-core-of-the- earth.htm

Meteorite Show similar metals to what we believe the core is made of!

#14: Journey to the Center of the Earth Textbook Time Use the red textbook to answer the following questions:  Pg. 130: “Analyzing Data” 1-4  Pg. 131 #’s 1 & 2  Pg. 135 #’s 1-3