Subject II. Igneous Rocks

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SubjectII. Igneous Rocks

• Mr. Mathews Earth Science 6th Grade

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Main Idea Details

• A. Classification of Igneous Rock

• Classified according to their _______ (where they
  formed),
• ______ (how they feel in terms of grain size,
  shape, and pattern),
• mineral _________ (the minerals that make up the
  rock).

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Main Idea Details

• 1. Origin (where they form)

• a. Extrusive Rock
• -forms from ____ that has exited the volcano or
  earths crust
• Example Basalt most common extrusive, forms
  most of crust beneath ocean floor.

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Main Idea Details

• 1. Origin (where they form)

• b. Intrusive Rock
• - forms when ______ cools and hardens inside the
  Earth.
• Example Granite most abundant intrusive,
  forms most of continental crust.

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Main Idea Details

• 2. Texture

• a. depends on ____ of crystals/grains
• b. The faster the lava cools, the _______ the
  crystals
• c. The slower the magma cools, the _____ the
  crystals.

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Summarize

• Igneous rocks are formed from lava or magma.
  Intrusive Igneous rocks are formed from magma and
  have large crystals/grains. Extrusive Igneous
  rocks are formed from lava and have small or no
  crystals/grains.

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B. Uses of Igneous Rocks

• Obsidian used to be used to make sharp tools
• Granite used for statues, bridges, buildings, and
  decoration
• Basalt used to make gravel
• Pumice used for cleaning and polishing