rocks by: paxton pennington. rock types igneous sedimentary metamorphic
Post on 18-Jan-2016
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ROCKS
By: Paxton Pennington
Rock Types
• Igneous• Sedimentary• Metamorphic
Igneous(From Fire)
• Formed form magma and molten rocks
• They can be formed in volcanoes • Crystal size is determined by
cooling time such as Extrusive or Intrusive
• Long cooling time indicates large crystals
• Short cooling time indicates small crystals
• Examples of igneous rocks are Obsidian, Pumice, Basalt
Features of Igneous Rocks
•Usually black In color Glassy texture
• Intrusive has large crystals and extrusive has coarse grain
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Sedimentary
• These rocks are formed from weathering and eroding• Rivers, creeks, oceans, and, Lake cause the formation
of sedimentary rocks• There are even organic ones such as Coal and
Limestone • Compaction, compression, cementation help form
theses rocks• Examples of Sedimentary rocks are limestone
Pebbles, Breccia
Metamorphic
• Formed under heat and Pressure• Mountains are metamorphic
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