1. Rocks Rock!

2. What is a rock?
Any solid mass of minerals that occur naturally

3. The Rock Cycle
Interactions among Earth’s water, air, & land cause rocks to change from one type to another.

4. Major Types of Rocks
Classified by their chemical composition & texture
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks

5. Igneous Rock Forms when magma cools and hardens
Can occur beneath the surface or as a result of volcanic eruptions

6. Igneous Composition Minerals: Granitic Andesitic Basaltic Quartz
Feldspar
Biotite Mica
Granitic
Andesitic
Basaltic

7. Igneous Texture Coarse-Grained Fine-Grained Glassy Porphyritic
SLOW COOLING
LARGE crystals
Fine-Grained
RAPID COOLING
SMALL crystals
Glassy
Cools so fast no crystals can form
Porphyritic
Crystals do not cool at same rate
Large crystals surrounded by small
crystals

8. Sedimentary Rock
Exposed igneous or metamorphic rocks undergoes weathering
This means the rock is physically and chemically broken down (by water, air, & living things) into sediments
Clastic Sedimentary Rock = physically broken
Chemical Sedimentary Rock = chemically broken
Sediments are compacted and cemented together to form sedimentary rock

9. Clastic Sedimentary Rocks
Grouped according to SIZE of sediments in the rock
Conglomerate
Rounded, gravel-size or larger
Breccia
Angular sediments
Sandstone
Sand sized sediments
Shale
Very fine-grained sediments (most common type)
Siltstone
Fine-grained rock

10. What are these?

11. (Bio)Chemical Sedimentary Rocks
Usually occurs when water evaporates off leaving a solid product
Limestone (from shells)
Chalk
Coquina (cemented shells)
Rock Salt
Chert
Flint
Rock Gypsum

12. Chalk
Limestone
Coquina
Flint
Chert
Rock Salt
Rock Gypsum

13. Metamorphic Rock
Under extreme pressure & temperature sedimentary or igneous rock will change into metamorphic rock

14. Foliated Metamorphic Rock
Have a layered or banded appearance
Gneiss & schist

15. Non-foliated Metamorphic Rock
Does not have a banded texture
Marble (calcite)
Quartzite
Anthracite

16. Magma
Metamorphic rock can melt to form magma if it is subject to additional pressure and temperature changes