Rocks

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Rocks

• Notes

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Processes that form rocks

• Melting
• Heating in the Earth causes rocks to melt forming
  magma (melted rock beneath the Earths surface).
• Cooling Hardening
• Magma rises to the surface, cools and hardens.
• Weathering, Erosion and Deposition
• Weathering breaks down rocks into sediment.
• Erosion is the movement of that sediment.
• Deposition is the process where the sediment is
  dropped off.

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Processes that form rocks

• Compacting Cementing
• Cementation is when sediments are glued together
  to form a rock. Pressure packs sediment
  together, cementing minerals together.
• Compaction is when sediments are pressed together
  through pressure
• Heat Pressure
• Heat from magma and pressure from overlying rock
  squeezes minerals changing rocks.

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Types of Rocks
Igneous Rock Forms from magma or lava (melted
rock on the Earths surface), melted rock.
Granite Diorite

• When it cools above ground it cools faster
  forming extrusive igneous rock (ex. granite).
• When it cools underground, it cools slower,
  forming intrusive igneous rock

Pumice Obsidian
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Types of Rocks

• Sedimentary Rock
• Formed from sediment that has become compacted
  and cemented together.
• Sediments are small pieces of material broken off
  rocks.
• When rocks are deposited in layers and they are
  compacted and cemented together, they form strata
  (a layered/striped look).
• Examples - Limestone, conglomerate and
  sandstone.

Conglomerate
Sandstone
http//www.physicalgeography.net/fundamentals/10f.
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Types of Rocks

• Metamorphic Rock
• Form from other rocks being heated and put under
  pressure.
• Rocks undergo metamorphosis, not melting.
• Example - Marble

Gneiss
Marble
http//www.physicalgeography.net/fundamentals/10f.
html
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Rock Cycle
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Rock Cycle
http//rst.gsfc.nasa.gov/Sect2/rock_cycle_800x609.
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Rock Cycle
http//www.victoria-sponge.com/media/ROCK20CYCLE
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