EOS 101 MIDTERM 2 VERIFIED STUDY GUIDE
Metamorphic Rock - Answers - A rock whose original (minerology, texture, or
composistion) has been changed in the solid state
Change in minerology - Answers - Same Composistion but different minerology
ex. Graphite after increased temp/pressure = diamond
Change in Composistion - Answers - Usually involves addition or removal of specific
liquids
ex. Clay after increased temp/pressure = Mica
Change in Texture - Answers - Change in Crystal Size or Arrangement
A: Crystal Size (usually increase in size)
ex. Shale (fine grained) after temp and pressure = Schist(course grained)
B: Crystal Arrangement (Grains more interlocked / pore space reduced
ex. Sandstone after temp/pressure = Quartzite
Change in Orientation (also type of texture) - Answers - Caused by two types of
stress
Uniform Stress (Confining Stress) - Answers - Pressure equal on all sides resulting
in random alignment (Non-Foliated)
Differential Stress - Answers - Pressure greater in direction resulting in prefeered
orientation (Foliated)
Foliation - Answers - Parallel alignment of minerals
Causes of Foliation - Answers - Rotation: rotation of exisiting/elongated plate
material
Flattening: Spherical Grains are flattened by slippage alongs planes
Recrystallization: produces new aligned materials that tend to crystallize in perp
direction
ex. Shale (sedimentary) -> Micro Mica Flakes ->Schist ->Gneist
Combo of Micas, Quarts, Feldspars etc.
low grade vs high grade metamorphic rocks - Answers - The hotter and more
pressure, the more fine the metamorhpic rock becomes
Metamorphic Rock - Answers - A rock whose original (minerology, texture, or
composistion) has been changed in the solid state
Change in minerology - Answers - Same Composistion but different minerology
ex. Graphite after increased temp/pressure = diamond
Change in Composistion - Answers - Usually involves addition or removal of specific
liquids
ex. Clay after increased temp/pressure = Mica
Change in Texture - Answers - Change in Crystal Size or Arrangement
A: Crystal Size (usually increase in size)
ex. Shale (fine grained) after temp and pressure = Schist(course grained)
B: Crystal Arrangement (Grains more interlocked / pore space reduced
ex. Sandstone after temp/pressure = Quartzite
Change in Orientation (also type of texture) - Answers - Caused by two types of
stress
Uniform Stress (Confining Stress) - Answers - Pressure equal on all sides resulting
in random alignment (Non-Foliated)
Differential Stress - Answers - Pressure greater in direction resulting in prefeered
orientation (Foliated)
Foliation - Answers - Parallel alignment of minerals
Causes of Foliation - Answers - Rotation: rotation of exisiting/elongated plate
material
Flattening: Spherical Grains are flattened by slippage alongs planes
Recrystallization: produces new aligned materials that tend to crystallize in perp
direction
ex. Shale (sedimentary) -> Micro Mica Flakes ->Schist ->Gneist
Combo of Micas, Quarts, Feldspars etc.
low grade vs high grade metamorphic rocks - Answers - The hotter and more
pressure, the more fine the metamorhpic rock becomes
