1. Igneous Rocks

2. Geo Facts Started in 1948 and located in SD The head is 26 m tall, his arm more than 70 m long Made of feldspar, diorite, and quartz Crazy Horse video segment

3. What is a ROCK? A rock is a group of minerals bound together In the picture you can see hornblende, feldspar, mica, and quartz

4. Rocks are found in Earth’s crust and mantle Rocks are classified according to how they were formed: – Igneous – Sedimentary – Metamorphic

5. Lava vs. Magma Magma is molten rock below Earth’s surface Lava is magma that flows out onto Earth’s surface Magma is often a slushy mix of rock, dissolved gases, and mineral crystals

7. The common elements present in magma are the same major elements that are found in Earth’s crust: – Oxygen, silicon, aluminum, iron, magnesium, calcium, potassium, and sodium Composition of Magma

8. Magma Classification Felsic magma – thick and slow moving Contains large amounts of silica Hardens into rocks of light-colored minerals (quartz and feldspar)

9. Mafic magma – hot, thinner and more fluid Contains small amounts of silica Hardens in to rocks of dark-colored minerals (hornblende, auguite, biotite) Magma Classification

10. Volcano Lava NatGeo volcano lava video segment

11. IGNEOUS Rocks are formed by the cooling and hardening of hot, molten rock, or magma, from inside the Earth. Igneous rock is slowly broken down by weathering and erosion.

12. Igneous Rock Formation Igneous rocks are classified by their mineral composition and texture. Intrusive igneous rocks form from underground magma. Extrusive igneous rocks form at Earth’s surface.

13. Texture Refers to the size, shape, and distribution of the crystals and grains that make up a rock Extrusive rock – small crystal size; lava cools very quickly Intrusive rock – large crystal sizes; lava cools very slowly

14. Intrusive RockExtrusive Rock