Rocks

Rocks

1. Igenous-from molten rocks

   • Plutonic rocks- from magma at depth (more crystallized)
     • Volcanic rock- from lava at surface (fine-grained,
       • Volcanic Glass- fast cooling at surface prevents crystals

2. Sedimentary- from by deposition of Earth's sediment; formed from mechanical break up of another rock

   • Lithification- compacts sediments together

3. Metamorphic- from heat/pressure

   • Contact Metamorphism- heat from magma chambers changes the adjacent rock
     • Regional Metamorphism- heat/pressure can affect rocks over big area

4. Law of Superposition: theory that strata at bottom are oldest

5. Classifying Rocks:

   • Grain size
     • Coarse= gravel
       • Medium= sand
         • Fine=silt
           • Very Fine= mud
   • Grain shapes
     • Angular
       • Sub-Angular
         • Sub-rounded
           • Rounded
   • Better sorted and rounded rocks traveled further from the surface

6. Rock Cycle:

Images and files in the map