Plate Tectonics - PowerPoint PPT Presentation

spencer
plate tectonics n.
Skip this Video
Loading SlideShow in 5 Seconds..
Plate Tectonics PowerPoint Presentation
Download Presentation
Plate Tectonics

play fullscreen
1 / 23
Download Presentation
Plate Tectonics
83 Views
Download Presentation

Plate Tectonics

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Plate Tectonics Liz LaRosa for use with my 5th Grade Science Class http://www.middleschoolscience.com 2009

  2. Earth’s Layers The Earth's rocky outer crust solidified billions of years ago, soon after the Earth formed. This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle.

  3. The Crust • Outermost layer • 5 – 100 km thick • Made of Oxygen, Silicon, Aluminum

  4. The Mantle • Layer of Earth between the crust and the core • Contains most of the Earth’s mass • Has more magnesium and less aluminum and silicon than the crust • Is denser than the crust

  5. The Core • Below the mantle and to the center of the Earth • Believed to be mostly Iron, smaller amounts of Nickel, almost no Oxygen, Silicon, Aluminum, or Magnesium

  6. Tectonic Plates

  7. Plate Tectonics • Greek – “tektonikos” of a builder • Pieces of the lithosphere(Earth’s crust) that move around • Each plate has a name • Fit together like jigsaw puzzles • Float on top of mantle similar to ice cubes in a bowl of water

  8. Continental Drift Alfred Wegener 1900’s theory that Continents were once a single land mass that drifted apart. Fossils of the same plants and animals are found on different continents Called this supercontinent Pangaea, Greek for “all Earth” 245 Million years ago Split again – Laurasia & Gondwana 180 million years ago http://members.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml

  9. Evidence of Pangea

  10. Sea Floor Spreading

  11. Sea Floor Spreading • Mid Ocean Ridges – underwater mountain chains that run through the Earth’s Basins • Magma rises to the surface and solidifies and new crust forms • Older Crust is pushed farther away from the ridge

  12. How Plates Move http://pubs.usgs.gov/gip/dynamic/unanswered.html

  13. Different Types of Boundaries http://pubs.usgs.gov/gip/dynamic/understanding.html

  14. Divergent Boundary – Arabian and African Plates Arabian Plate Red Sea African Plate

  15. Divergent Boundary – Iceland http://pubs.usgs.gov/gip/dynamic/understanding.html

  16. Divergent Boundary - Oceanic http://www.geology.com

  17. Divergent Boundary - Continental http://www.geology.com

  18. Convergent Boundary – Indian and Eurasian PlatesThe red marker identifies the Himalaya Mountains Eurasian Plate Indian Plate

  19. Convergent Boundary – Oceanic & Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  20. Convergent Boundary – Oceanic & Oceanic Note – plates are reversed http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  21. Convergent Boundaries - Continental http://pubs.usgs.gov/gip/dynamic/understanding.html & http://www.geology.com

  22. Transform Boundary – San Andreas Fault www.geology.com

  23. Review • Name the 3 main layers of the Earth • What is a tectonic plate? • What was Pangea? • What is Sea-Floor spreading? • Name the three different types of plate boundaries and one location on Earth for each one