Rock Cycle

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Rock Cycle
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There are three major types of rocks

• Igneous
• Sedimentary
• Metamorphic

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Igneous rocks

• Igneous rocks are formed when molten rock (magma)
  from within Earth cools and solidifies.
• There are two types
• intrusive igneous rocks solidify beneath Earth's
  surface
• extrusive igneous rocks solidify at the surface.
• Examples Granite, basalt, obsidian

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Volcanoes lava or magma forms new igneous rocks
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Sedimentary rocks

• Sedimentary rocks are formed when sediment (bits
  of rock plus material such as shells and sand)
  gets packed together by cementation and
  compaction.
• They can take millions of years to form.
• Most rocks that you see on the ground are
  sedimentary.
• Examples Limestone, sandstone, shale

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Sedimentary
The sand at the beach is made of little pieces of
rock that broke off larger rocks. These little
broken pieces are called sediment. There are many
types of sediment including sand, mud, pebbles,
and even dust. It takes a very long time,
thousands and thousands of years, but sediments
can form a rock if they become stuck
together.(cementation compacted)
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Metamorphic rocks

• Metamorphic rocks are sedimentary or igneous
  rocks that have been transformed by heat, and
  pressure (or both).
• Metamorphic rocks are usually formed deep within
  Earth, during a process such as mountain
  building.
• Examples Schist, marble, slate

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Metamorphic Rock
Heat and pressure change the previous sedimentary
rock into a metamorphic rock.
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The Rock Cycle

• The rock cycle explains how the different types
  of rock form.
• The three types of rock at Earths mantle melt
  into magma.
• Magma that cools and hardens underground forms
  intrusive igneous rock.
• Weathering breaks the rock into sediment. Erosion
  causes the sediment to move to other locations.
  These sediment are glues together by cementation.
• Pressure squeezes and compacts the sediment
  together, forming sedimentary rock.
• Heat and pressure change igneous and sedimentary
  rock into metamorphic rock

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Rocks can change into other rocks! The stuff that
rocks are made from stays the same, but the rocks
do not. Over time rocks are recycled into new
rocks. Moving parts of Earth's surface layer help
rocks recycle!