rocks and minerals

rocks

• naturallt occuring aggregates of minerals

• petrology: branch of science that studies rocks

types of rocks:

• igneous:

  • rocks that cooled from molten magma

  • may form beneath of above surface of earth

  • 2 types of igneous rocks:

    • intrusive: formed within the earth, large crystals

    • extrusive: formed at surface of earth, fine grained crystals

• sedimentary:

  • formed from sediments

  • types:

    • clastic: formed from fragments formed from weathering

    • chemical: form by precipitation of minerals

    • organic: form by accumulation of living organisms

• metamorphic:

  • heat, pressure, chemically modified rocks

  • happens deep below the earths surface

  • types:

    • foliated: layers

    • non foliated: no layers