Although a few rocks are made up of one mineral, most rocks are made up of a solid mixture of minerals. Therefore the basic definition of a rock is any solid mass of mineral or mineral like material that occurs naturally on Earth. There are three types of rocks: igneous rocks, sedimentary rocks, and metamorphic rocks. The rock cycle consists of the processes that cause rocks to change forms.  Interactions between water, air, and land cause the rock cycle to take place.

• Rock Transformations:
  • Igneous rock:
    • Can be transformed into metamorphic rock under extreme pressure and high temperature
    • May be transformed into sediment (weathered pieces of Earth materials) as a result of weathering (the process of rocks being broken down by water, air, and living things) and erosion. Sediment may later undergo compaction, dewatering, and lithification to form sedimentary rock.
    • Can melt to form magma (molten rock that forms underneath the Earth’s surface) under high temperature conditions.
      • Magma hardens and cools beneath the Earth’s surface to form igneous rocks.
  • Metamorphic rock:
    • May be transformed into sediment as a result of weathering and erosion. Sediment may later undergo compaction, dewatering, and lithification to form sedimentary rock.
    • Can melt to form magma under high temperature conditions
  • Sedimentary rock:
    • Can be transformed into metamorphic rock under extreme pressure and temperature
    • May be transformed into sediment as a result of weathering and erosion. Sediment may later undergo compaction, dewatering, and lithification to again form sedimentary rock.

Any of the three types of rock can be transformed into any of the other three types of rock.  The series of changes that take place to change one rock into another type of rock is called the rock cycle.  It is a continuous process.

 

 

 

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