Rock Cycle Homework: Read 75-85 Do Cornell notes (key terms and Vocab)

1. Rock CycleHomework: Read 75-85Do Cornell notes (key terms and Vocab) Bell Ringer quiz: What is a mineral? What is a rock? What powers the Earth’s rock cycle? How do fine grained igneous rocks form?

2. Rocks • A rock is any solid mass of mineral or mineral-like matter that occurs naturally as part of our planet. • Some rocks are a single mineral, but most rocks are combinations of minerals. • Rocks are classified into three major groups: • Igneous • Sedimentary • Metamorphic

3. Rocks Igneous rock is formed by the crystallization of molten magma. Sedimentary rock is formed from the weathered products of rocks that have been transported, deposited, compacted, and cemented. Metamorphicrock is formed by the alteration of pre-existing rock deep within Earth (but still in the solid state) by heat, pressure, and/or chemically active fluids.

4. Rock Cycle Interactions among Earth’s water, air, and land can cause rocks to change from one type to another. This continuous process is called the rock cycle. Shows the interrelationships among the three rock types

6. Rock Cycle • Magma is molten material that forms deep beneath the Earth’s surface. • When magma cools and hardens beneath the surface or from volcanic eruptions, igneous rocks form. • Lava is magma that reaches the surface. • Weathering is a process in which rocks are physically and chemically broken down by water, air, and living things.

7. Continued Sediment is weathered pieces of Earth elements. Eventually sediments are compacted and cemented to form sedimentary rocks. If the sedimentary rocks get buried deep under the Earth it would be subjected to extreme temperature and pressure. It will then change into metamorphic rocks.

8. Power for the Rock Cycle Processes driven by heat from the Earth’s interior are responsible for forming both igneous rock and metamorphic rock. Weathering and the movement of weathered materials are external processes powered by energy from the sun. External processes produce sedimentary rocks.

9. Continued • Journey through the Rock Cycle. • How might a sedimentary rock become an igneous rock? • The rock could become buried at depths where temperatures and pressures were great enough to cause melting. When the melted material (magma) cooled and hardened, an igneous rock would form. • What processes change sedimentary rock into another sedimentary rock? • Weathering, transportation, deposition, compaction, and cementation

10. Igneous Rocks • Fire! • Intrusive igneous rocks are formed when magma hardens beneath Earth’s surface. • Erosion exposes these rocks. • Magma has many elements and gases. As magma rises, it cools allowing elements to bond and form minerals, • Granite is a common intrusive igneous rock. • Extrusive igneous rocks are formed when lava hardens.

11. Classification • Classified by texture and composition Texture • Coarse-grained texture is caused by slow cooling resulting in larger crystals. • Fine-grained texture is caused by rapid cooling resulting in smaller, interconnected mineral grains. • Glassy texture is caused by very rapid cooling. • Porphyritic texture is caused by different rates of cooling resulting in varied sized minerals.

12. Classification Composition • Granitic composition rocks are made mostly of light-colored quartz and feldspar. • Basaltic composition rocks are made mostly of dark-colored silicate minerals and plagioclase feldspar. • Andesitic composition rocks are between granitic light-color minerals and basaltic composition dark-colored minerals. • Ultramafic composition rocks are made mostly from iron and magnesium-rich minerals.