Plate Boundaries: Convergent, Divergent, Transform

What are the major plate tectonic boundaries?

Video lecture on divergent, transform, and convergent types of plate boundaries. Recorded during a 2007 teacher workshop on earthquakes and tectonics. Speaker is Dr. Robert Butler, University of Portland Oregon

Three main types of plate boundaries:

  • Divergent: extensional; the plates move apart. Spreading ridges, basin-range
  • Convergent: compressional; plates move toward each other. Includes: Subduction zones and mountain building.
  • Transform: shearing; plates slide past each other. Strike-slip motion.


Keypoints:

Discovery

  • Where do the most earthquakes occur worldwide?
  • Where do most volcanoes occur?
  • What do the concentrations of earthquakes tell us about plate interaction?
  • Does the location of earthquakes and volcanoes show a pattern? If so, what tectonic process may be responsible? (compression, extension, shearing)

Total Time: 1min 25s
Level: Novice

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