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• Igneous Rock


  Formed from hardening and crystallization of magma or molten material that originates deep within the earth
• Types of Igneous Rock

  • Intrusive or plutonic igneous rocks
  • Extrusive or volcanic igneous rocks
• Intrusive or plutonic igneous rocks


  • Formed from solidification of magma below the surface
  • Have large crystals of minerals that formed over time through slow process crystallization in a magma
  • Have a long cooling time
• Intrusive or plutonic igneous rocks

  • Granite
  • Diorite
  • Gabbro
  • Pegmatite
  • Peridotite
• Extrusive or volcanic igneous rocks

  • Formed through faster rate of solidification of lava on the surface of the Earth
  • Become glassy in appearance due to less crystallization or vesicular like Scoria due to the air that was trapped inside when they solidified and formed on the surface of the Earth
• Extrusive or volcanic igneous rocks

  • Andesite
  • Basalt
  • Dacite
  • Obsidian
  • Pumice
  • Rhyolite
  • Tuff
• Metamorphic Rock

  Forms from pre-existing rocks: either metamorphic, igneous, sedimentary
• Metamorphic Rocks

  • Quartzite
  • Marble
  • Slate
  • Phyllite
• Magmatic Ore Deposits

  Valuable substances are concentrated within an igneous body through magmatic processes such as crystal fractionation, partial melting, and crystal settling
• Magmatic processes that concentrate ore minerals

  1. Partial melting

  2. Crystal fractionation

  3. Crystal settling
• Crystal Settling


  As magma cools down, heavier minerals tend to crystallize early and settle at the lower portion of the magma chamber
• Minerals concentrated through crystal settling

  • Chromite (FeCr204)
  • Magnetite (Fe3O4)
  • Platinum (Pt)
• Fractional Crystallization

  The residual melt contains high percentage of water and volatile substances that are favorable for the formation of pegmatites
• Minerals concentrated through fractional crystallization

  • Lithium
  • Gold
  • Boron
  • Rare elements
  • Heavy metals
• Hydrothermal Ore Deposits


  Concentration of valuable substances by hot aqueous (water-rich) fluids flowing through fractures and pore spaces in rocks
• Hydrothermal solutions


  Hot, residual watery fluids derived during the later stages of magma crystallization and may contain large amount of dissolved metals<|>Can also originate from the ground water circulating at depth that is being heated up by a cooling and solidifying igneous body or along depths with known geothermal gradient
• Precipitation of dissolved substances from hydrothermal solutions

  As the metal enriched hot waters move into cooler areas in the crust, the dissolved substances may start to precipitate
• Examples of Hydrothermal Deposits

  • Vein type deposits
  • Disseminated deposits
  • Massive sulfide deposits
  • Stratabound Ore deposits
• Metamorphism

  Transformation of one rock to another
• Types of Metamorphism

  • Regional due to changes in pressure and temperature over large region of the crust
  • Contact mainly by heat due to contact with magma
• Sedimentary Rock

  These rocks often start as sediments carried in rivers and deposited in lakes and oceans. When buried, the sediments lose water and become cemented to form rock.
• Classification of Sedimentary Rocks

  • Clastic sedimentary rock
  • Chemical sedimentary rock
  • Organic sedimentary rock
• Clastic sedimentary rocks

  • Breccia
  • Conglomerate
  • Sandstone
  • Siltstone
  • Shale
• Chemical sedimentary rocks

  • Rock salt
  • Iron ore
  • Chert
  • Flint
  • Dolomites
• Rock Cycle

  The continuous process of the formation, breakdown, and reformation of rocks
• Types of Mineral Resources

  • Metallic mineral deposits
  • Non-metallic mineral deposits
• Metallic mineral deposits

  • Gold
  • Silver
  • Copper
  • Platinum
  • Iron
• Non-metallic mineral deposits

  • Talc
  • Fluorite
  • Sulfur
  • Sand
  • Gravel
• Ore Deposits

  The geologic processes involved in the rock cycle play major role in the accumulation and concentration of valuable elements / minerals
• Types of Ore Deposits

  • Magmatic ore deposits
  • Hydrothermal ore deposits
  • Sedimentary ore deposits
  • Placer ore deposits
  • Residual ore deposits