I. Rocks

A. Rock Cycle (fig. 1.12)

 

B. Rock Types (fig. 1.12, 1.13)

  1. Igneous

      2. extrusive

      intrusive

  2. Sedimentary
  3. Metamorphic

C. Processes

  1. cooling - converts magma into igneous rock
  2. weathering and erosion - converts a pre-existing rock into sediment
  3. lithification - converts loose sediment into solid rock
  4. metamorphism - changes a pre-existing rock into a metmorphic rock
  5. melting - converts a metamorphic rock into magma
  6. repeat the cycle

D. Geometry of Rock units

  1. igneous
    1. intrusive - magma comes up from below and cools in cracks (tabular shapes) or in irregular, blob-shapes (pages 102-103)
    2. extrusive - forms in layers on the surface like sedimentary rocks
  2. Sedimentary - form in (usually horizontal) layers on surface of Earth
  3. Metamorphic - form underground at high pressure
    1. folding
    2. faulting
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