2. Igneous Rocks By: Ana 4B

3. How the rock is formed? Igneous rocks are those that form by cooling from a melt. If they erupt from volcanoes as lava, they are called extrusive rocks. If they cool underground but near the surface, they are called intrusive and often have visible, but tiny mineral grains. If they cool very slowly deep underground, they are called plutonic and have large mineral grains. Igneous rocks are those that form by cooling from a melt. If they erupt from volcanoes as lava, they are called extrusive rocks. If they cool underground but near the surface, they are called intrusive and often have visible, but tiny mineral grains. If they cool very slowly deep underground, they are called plutonic and have large mineral grains.

4. Where do the Igneous Rocks fit into the rock cycle? Igneous rock forms when magma cools and makes crystals. Magma is a hot liquid made of melted minerals. The minerals can form crystals when they cool. Igneous rock can change into sedimentary or metamorphic rock. Igneous rock forms when magma cools and makes crystals. Magma is a hot liquid made of melted minerals. The minerals can form crystals when they cool. Igneous rock can change into sedimentary or metamorphic rock.

5. The Rock Cycle

6. Properties The two major properties used to classify igneous rock are: 1. Crystal Size Small crystals are indicative of rapid above ground cooling of lava into what is classified as extrusive igneous rock such as basalt. Large crystals are indicative of slow cooling magma underground, resulting in what is called intrusive igneous rock such as granite.

7. Properties 2. Chemistry or Mineralogy Igneous rock, whether intrusive or extrusive, that is high in silica is classified as felsic. Igneous rock that is low in silica, is classified as mafic. Rocks falling between the two are classified as intermediate.

8. Uses of Igneous Rocks Jewelry Jewelry Lava Soap Lava Soap Building Materials Building Materials Landscaping Landscaping Gravestones Gravestones Decoration on Buildings. Decoration on Buildings.

9. Where can this type of rock be found? Igneous rock can be found on the surface in areas of current or past volcanism or in uplifted and eroded areas of past plutonic intrusions, deep underground nearly anywhere, or in areas of past or present glaciation, where igneous rock has been eroded and deposited. Igneous rock can be found on the surface in areas of current or past volcanism or in uplifted and eroded areas of past plutonic intrusions, deep underground nearly anywhere, or in areas of past or present glaciation, where igneous rock has been eroded and deposited.

10. Types of Igneous rocks? There are many types here are some : There are many types here are some : Basalt Basalt Granite Granite Obsidian Obsidian Dunite Dunite Tuff Tuff

11. Quiz 1.The Mount Rushmore National Monument is carved from the granite of South Dakota's Black Hills. What type of rock is granite? a. Igneous b. Metamorphic c. Sedimentary d. None of the above

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13. Quiz What type of igneous rock makes up most of the ocean floor? What type of igneous rock makes up most of the ocean floor? a. Basalt a. Basalt b. Granite b. Granite c. Lucite c. Lucite d. Shale d. Shale

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15. Quiz What rock type is formed from the slow cooling of magma under the earth's surface What rock type is formed from the slow cooling of magma under the earth's surface a. Extrusive igneous a. Extrusive igneous b. Intrusive igneous b. Intrusive igneous c. Metamorphic c. Metamorphic d. Sediment d. Sediment

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17. Quiz Which characteristic is common to extrusive igneous rocks? Which characteristic is common to extrusive igneous rocks? A. Crystals A. Crystals B. Fossils B. Fossils C. Glassy surface C. Glassy surface D. Ribbonlike layers D. Ribbonlike layers

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19. Quiz (Easy one) Quiz (Easy one) The interrelationship among the three rock types is identified as which of the following? The interrelationship among the three rock types is identified as which of the following? A. The rock cycle A. The rock cycle B. The rock formation B. The rock formation C. The rock helix C. The rock helix D. The rock metamorphosis D. The rock metamorphosis

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