1 / 33

Plate Tectonics

Plate Tectonics. What is Plate Tectonics. The Earth’s crust and upper mantle are broken into sections called plates These plates move around on top of the asthenosphere like rafts. Lithosphere. The crust and part of the upper mantle = lithosphere

orla-spence
Télécharger la présentation

Plate Tectonics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Plate Tectonics

  2. What is Plate Tectonics • The Earth’s crust and upper mantle are broken into sections called plates • These plates move around on top of the asthenosphere like rafts

  3. Lithosphere • The crust and part of the upper mantle = lithosphere • Less dense than the material below it so it “floats”

  4. Asthenosphere • The “plastic” layer below the lithosphere • The plates of the lithosphere float on the asthenosphere

  5. 2 Types of Plates • Ocean plates - plates below the oceans • Continental plates - plates below the continents

  6. Plate Boundaries

  7. Divergent Boundaries • Boundary between two plates that are moving apart or rifting  

  8. Examples of Divergent Boundaries • Mid-ocean ridges • rift valleys

  9. Convergent Boundaries • Boundaries between two plates that are colliding   • There are 3 types…

  10. Type 1 • Ocean plate colliding with a less dense continental plate • Subduction : occurs where the more dense plate slides under the less dense plate

  11. Subduction Zones occur here Deepocean trenches may occur here Mountains and volcanoes may occur

  12. Andes Mountains, South America

  13. Type 2 • Ocean plate colliding with another ocean plate • The more dense plate slides under the less dense plate creating a subduction zone called a TRENCH

  14. Aleutian Islands, Alaska

  15. Type 3 • A continental plate colliding with another continental plate • a place where folded and thrust faulted mountains form.

  16. Transform Fault Boundaries • Boundary between two plates that are sliding past each other • EARTHQUAKES along faults

  17. San Andreas Fault, CA

  18. Questions... • What are the three types of boundaries? • What direction do plates go for each? • Which boundary has a subduction zone…what occurs at a subduction zone?

  19. Causes of Plate Tectonics

  20. Convection Currents • Hot magma in the Earth moves toward the surface, cools, then sinks again. • Creates convectioncurrents beneath the plates that cause the plates to move.

  21. Questions... • What causes plates to move? • How is a convection current formed?

  22. New sea-floor is produced at what type of boundary? A. convergent B. divergent C. transform D. I don’t know

  23. Mt. Everest was produced by this type of plate boundary. A. convergent B. divergent C. transform D. I Don’t Know

  24. This type of boundary, found near San Francisco CA, is the result of shear force. A. convergent B. divergent C. transform D. I Don’t Know

More Related