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Rock types - Coggle Diagram

- - - - Metamorphic rocks that have their grains arranged in parallel layers or bands are said to be foliated.
      - Foliated rocks form when minerals in the original rock flatten under pressure.
    - - The mineral grains in these rocks are arranged randomly and do not form layers.
- - - - Masses of intrusive igneous rocks are named for their size and shape.
      - Large intrusive bodies, termed plutons, tend to cool slowly and make coarse grained textures.
      - Large intrusive bodies, termed plutons, tend to cool slowly and make coarse grained textures.
      - Types of plutons
        
        Dikes and sills, forming from thin sheets of magma pushing along cracks, cool much more quickly.
        
        Pegmatites also cool fairly quickly, but their high water content promotes rapid crystal growth and thus very coarse textures.
    - - Extrusive igneous rock is formed by magma that reaches Earth’s surface along deep cracks and at volcanic vents.
      - This magma that flows onto the surface is called lava.
      - Most types of lavas cool rapidly on the Earth surface, resulting in the formation of rocks composed of very small crystals or no crystals at all.
- - - - Clastic sedimentary rocks are made of broken fragments of plants, animals, and other rocks. These loose sediments are compacted and cemented together to form solid rock.
      - Erosion moves sediment to a different location, where they are then deposited. Here, layer upon layer, of sediment builds up. Pressure from the upper layers pushes down on the lower layers. If the sediments are small, they can stick together and form solid rock. This is called compaction.
      - If sediments are large, pressure alone can't make them stick together. Larger sediments have to be cemented together. As water moves through soil and rock, it picks up materials released from minerals during weathering. The resulting solution of water and dissolved materials move through open spaces between sediment. Cementation, occurs when minerals such as quartz, calcite, and hematite are deposited between the pieces of sediment.
      - If the sediment is rounded, the rock is called conglomerate. If the sediments have sharp angles, the rock is called Limestone forms in the oceans, where many living things, such as coral, clams, and oysters, have hard shells or skeletons made of calcite. When these animals die, their shells pile up on the ocean floor..
    - - Chemical sedimentary rocks form when dissolved minerals come out of solution and crystallize. Minerals collect when seas or lakes evaporate. The deposits of minerals that fall out of solution form rocks.
      - Chemical rocks can also form from mineral deposits left when seas or lakes evaporate (For example, rock salt)
    - - Organic sedimentary rock forms where the remains of plants and animals are deposited in thick layers.
      - Coal forms from the remains of swamp plants buried in water.
      - Limestone forms in the oceans, where many living things, such as coral, clams, and oysters, have hard shells or skeletons made of calcite. When these animals die, their shells pile up on the ocean floor.