Composition of the Earths Crust

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Composition of the Earths Crust

• Rock Forming
• Minerals

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• There are about 4000 minerals found on Earth
• Only 30 are common
• Most (diamonds, gold, ) are rare
• A handful (8-11) make up most of the rocks found
  in the Earths crust

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Composition of the Earths Crust
8 Elements Make Up 97 of the Earths Crust
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High Temperature
Low Temperature
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Families of Rock Forming Minerals

• Silicates
• Most common minerals
• Composed mainly of silicon (Si) and oxygen (O)
• 90 of the Earths Minerals are silicates
• Feldspars (KAlSi3O8 ) (make up 60 of RFM)
• Quartz (SiO2)
• Micas (Al2O3, K2O, )

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Families of Rock Forming Minerals

• Silicates
• Silicon-Oxygen Tetrahedron basic structure for
  silicate minerals (SiO4)

O
Si
O
O
O
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Families of Rock Forming Minerals

• Carbonates
• 2nd most abundant mineral group
• Composed mainly of carbonate (CO3)
• Common mineral is Calcite (CaCO3)

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Families of Rock Forming Minerals

• Oxides
• Basic composition is iron oxide (Fe2O3)