Plate Tectonics

Anotações:

• The deeper you go the higher  the temperature gets.

1. Exploring Inside Earth
   1. Evidence from rock samples

      Anotações:

      • Scientists drill holes into Earth to find out what is inside.
   2. Evidence from seismic waves

      Anotações:

      • Scientists send seismic waves into Earth.
2. Journey to the center
   1. Temperature

      Anotações:

      • The deeper you go, the higher the temperature.
   2. Pressure

      Anotações:

      • The deeper, the stronger the pressure.
3. The Mantle
   1. Asthenosphere

      Anotações:

      • The asthenosphere is the softest part of the mantle.
   2. Lithoshere

      Anotações:

      • The lithosphere is the upper part of the mantle and the lower part of the crust.
   3. Lower Mantle

      Anotações:

      • The lower mantle is solid and extends down to the core.
4. The Crust

   Anotações:

   • The crust is a solid layer of rock the is 4 to 5 kilometers thick.
5. The Core
   1. The Outer and Inner Core

      Anotações:

      • The outer core is liquid, but the inner core is solid.
   2. The Core and Earth's magnetic Field

      Anotações:

      • Our planet is like a giant magnet bar, and the core is the magnet.

1. Convection currents in Earth
   1. Caused By Mantle

      Anotações:

      • Currents are caused by the heat from the core and mantle.
2. Convection currents
   1. A current that transfers heat

      Anotações:

      • A convection current is continuos as long as there is heat.
3. Types of Heat Transfer
   1. Radiation

      Anotações:

      • Radiation is transfer of energy through space(air).
   2. Convection

      Anotações:

      • Convection is heat transfer through fluids.
   3. Conduction

      Anotações:

      • Conduction is heat transfer through contact.

1. Continental Drift
   1. Evidence From Land Features

      Anotações:

      • The continents all fit together, just like a jigsaw puzzle.
   2. Evidence From Fossils

      Anotações:

      • The fossils of the same organisms were found in far apart continents, today.
   3. Evidence From Ancient Climate Zones

      Anotações:

      • Fossils of tropical plants found in Antartica and sediments from glaciers found in Africa conclude that climate was different back then, meaning that the continents either moved away from the equator or to the equator.
2. Wegner's Hypothesis Rejected
   1. Wegner's hypothesis is rejected.

      Anotações:

      • Most geologists rejected Wegner's hypothesis because he couldn't identify the cause of continental drift.

1. Mid-Ocean Ridges

   Anotações:

   • Scientists use Sonar to map outh a mid-ocean ridge(an underwater mountain chain).
2. What is Sea-Floor Spreading

   Anotações:

   • The sea-floor spreads apart along mid-ocean ridges, carrying continents with them.
3. Evidence for sea-floor spreading
   1. Evidence from molten material

      Anotações:

      • Scientists discover molten material and use it for evidence.
   2. Evidence from drilling samples

      Anotações:

      • Drilling samples from the ocean floor give evidence of sea-floor spreading.
   3. Evidence from Magnetic Stripes

      Anotações:

      • Rock patterns give evidence of sea-floor spreading.
4. Subduction at Trenches
   1. The Process of Subduction

      Anotações:

      • A part of the process of subduction is when the ocean floor sinks into the mantle.
   2. Subduction and Earth's Oceans

      Anotações:

      • Sea-floor spreading and subduction are changing the size and shape of the oceans.

1. How Plates Move

   Anotações:

   • The theory of plate tectonics  explain the activities of Earth's plates.
2. Plate Boundaries
   1. Spreading Boundaries

      Anotações:

      • Spreading boundaries happen when two plates spread apart.
   2. Colliding Boundaries

      Anotações:

      • Colliding boundaries occur when two plates come together.
   3. Sliding Boundaries

      Anotações:

      • Sliding boundaries occur when two plate slide past each other, moving in opposite directions.