Plate tectonics

Card Set Information

Plate tectonics
2014-02-23 17:06:47
plate tectonics

Chapter 2
Show Answers:

  1. Active mountain belts are most likely to be found ________.
    along the margins of continents
  2. During various times in the geologic past, the polarity of Earth's magnetic field as been reversed.
  3. In correct order from the center outward, Earth includes which units?
    inner core, outer core, mantle, crust
  4. In the early part of the 20th century, _________ argued forcefully for continental drift.
    Alfred Wegener
  5. Internally, the Earth consists of spherical shells with different compositions and densities.
  6. New oceanic crust and lithosphere are formed at ________.
    Divergent plate boundaries
  7. Pull-apart, rift zones are generally associated with a ________ plate boundary.
  8. The _______ forms the relatively cool, brittle plates of plate tectonics.
  9. The _______ is an example fo an active, continent-continent collision.
    northward movement of India into Eurasia
  10. The former, late Palezoic super continent is known as ________.
  11. Which of the following best decribes the fundemental concept of superposition?
    Older strata genearlly are deposited on younger strata without intervening, intermediate age strata
  12. Which of the following energy sources is thought to drive the lateral motions of Earth's lithsopheric plates?
    export of heat from deep in the mantle to the top of the asthenosphere
  13. Oceanic-continental convergence
    Happens when the leading edge of a plate capped with continental crust converges with a slab of oceanic lithosphere. The oceanic slab sinks down into the mantle and begins to melt. May give rise to volcanic eruptions.
  14. oceanic-oceanic convergence
    Two ocean slabs converge, and one descends below the other causing volcanic activity. Volcanoes grow from the ocean floor.
  15. Continental-continental convergence
    Causes collision between the two convergent fragments which folds and deforms the rocks along the continental margins, causing mountains.
  16. Transform plate boundaries
    When plates slide horizontally past one another without the production or destruction of lithosphere.
  17. Evidence supporting plate tectonics.
    • 1.Ocean drilling:
    • 2. Mantle plumes:
    • 3. Paleo-magnetism
    • 4. Apparent polar wandering
    • 5. Magnetic reversals and seafloor spreading
  18. Slab pull
    Drives plate motion because cold slabs of oceanic lithosphere are more dense than the underlying warm asthenosphere and sink.
  19. ridge push
    Contributes less to plate motion than slab pull, driven by gravity, causes slabs of lithosphere to slide down the flanks of a ridge.