ELS Week 6 - Rocks - Earth's Material

• Rock


  is any naturally occurring solid mass or aggregate of minerals or mineraloid matter.
• Types of Rocks

  • Igneous Rock
  • Sedimentary Rock
  • Metamorphic Rock
• Igneous Rock


  (derived from the Latin word ignis meaning fire) is formed through the cooling and solidification of magma or lava.
• Two Types of Igneous Rock

  • Extrusive Rock
  • Intrusive Rock
• Extrusive Rock


  formed on the surface
• Intrusive Rock


  formed underground or plutons.
• Intrusive Igneous Rock (Plutonic)


  is formed when magma penetrates existing rock,

  crystallizes, and solidifies underground to form intrusions, for

  example, plutons, batholiths, dikes, sills, laccoliths, and volcanic

  necks.
• Extrusive Igneous Rock (Volcanic)


  refers to the mode of igneous volcanic

  rock formation in which hot magma from inside the Earth flows

  out (extrudes) onto the surface as lava or explodes violently

  into the atmosphere to fall back as pyroclastic or tuff.
• Sedimentary Rock


  are types of rock that are formed by the

  accumulation or deposition of small particles and subsequent

  cementation of mineral or organic particles on the floor of oceans

  or other bodies of water at the Earth's surface.
• Metamorphic Rock


  arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form".
• The Rock Cycle is a concept used to explain how the three basic rock types are related and how Earth processes, over geologic time, change a rock from one type into another.