GEOG150 - CH2 (Geology)

  1. What are the three tectonic plates found in California?
    • Pacific Plate
    • North American Plate
    • Juan de Fuca Plate
  2. theory of plate tectonics
    explains earth's lithospheric structure and mountain-building processes
  3. How many years ago is it believed was the last time the plates were all joined together?
    250 million years ago
  4. What was Pangaea?
    a Greek word meaning "whole land".

    was known as the supercontinent that the now 7 tectonic plates once were when it was whole approximately 250 million years ago.
  5. What is the oceanic crust composed of?
    dense, heavy basaltic rocks
  6. What is the continental crust composed of?
    lighter, granitic rocks
  7. What layer of the earth makes up the tectonic plates?
  8. Lithosphere
    The lithosphere is composed of the continental and oceanic crusts along with the hard upper mantle.
  9. What are the three types of plate boundaries?
    • Convergent Boundary
    • Divergent Boundary
    • Transform (or Transcurrent) Boundary
  10. Convergent Boundary
    • where an oceanic plate meets a continental plate
    • long mountain ranges on land and deep trenches in the ocean form
  11. Divergent Boundary
    • one plate splits into two plates
    • deep valleys form on land and mid-oceanic ridges develop in the ocean
  12. Transform/Transcurrent Boundary
    when two plates slide laterally past each other
  13. Which type of boundary creates new crust in the lithosphere?
    Divergent Boundary
  14. Which type of boundary neither creates or destroys crust from the lithosphere?
    Transform/Transcurrent Boundaries
  15. Which type of boundary destroys crust from the lithosphere?
    Convergent Boundary
  16. What ancient plate has mostly subducted under the North American plate?
    Farallon Plate


  17. Which are the names of the plates that are remnants of the Farallon Plate?
    • Juan de Fuca (North of California)
    • Cocos Plate (South of California)
  18. Focus
    during an earthquake, it is the underground location where the sudden movement occurs from energy built up that is released at a fault line
  19. Epicenter
    the point on the earth's surface right above the focus
  20. Magnitude
    the amount of energy released during an earthquake
  21. Richter Scale
    • a method developed by California geologist Charles Richter
    • scale from zero to twelve (not felt to catastrophic)
  22. What is the difference between a Richter Scale rating of 4 to 5?
    a shaking amplitude that is 10 times larger
  23. Creep
    The slow, steady downhill movement of soil and loose rock on a slope
  24. Intensity
    the ground motion and resultant impact of an earthquake
  25. What is a method that is used to measure an earthquake's intensity?
    Mercalli Scale
  26. Blind Thrust Fault
    a fault line where the rocks primarily shift vertically but the fracture does not reach the surface
  27. Opposite to (1)_______ processes, which tend to increase the relief of the earth's surface, the (2)________ processes tend to lessen the relief by weathering and eroding down higher lands and filling up lower lands with the resulting sediments.
    • 1. internal
    • 2. external
  28. Examples of internal forces...
    earthquakes, fault movements, and volcanic eruptions
Card Set
GEOG150 - CH2 (Geology)
Geological and geomorphic processes and the resulting landforms