1. Rocks, Rocks, and More Rocks

2. Types of Rocks Igneous rock Forms when magma cools and hardens
Can form underground or above ground
Types of igneous rock:
Granite
Scoria
Pumice
Obsidian
Pumice
Obsidian
Scoria

3. Types of Rocks Wind and water can break igneous rock into sediments.
When the sediments are cemented into a layer over time, igneous rock becomes sedimentary rock.
What causes the cementation?
Sediments
Igneous Rock
Sedimentary Rock
Wind and Water
Cementation
Cementation is caused by pressure from added sediments on top. The pressure squeezes the sediment into layered solids in a process called lithification.

4. Types of Rocks Sedimentary Rock
Common types include chalk, limestone, and clay
Often contains fossils
Types of Sedimentary rocks
Clastic: made up of different rock fragments
Biogenic: contain materials from organisms such as corals
Precipitate: rocks formed when water evaporates such as halite (rock salt left behind after sea water evaporates)

5. Weathering and Erosion
Types of Rocks
Weathering and erosion will revert sedimentary rocks back to sediments.
Heat and pressure change sedimentary rock to metamorphic rock.
Sediments
Sedimentary Rock
Metamorphic Rock
Weathering and Erosion
Heat and Pressure

6. Types of Rocks Metamorphic Rock
Make up a large part of the Earth’s crust
Common examples include slate, shale, and mudstone
Can go through foliation, a process where the randomly distributed minerals in the rock become organized in a parallel manner
Foliation can cause cleavage or breakage of the rock at weak cracks

7. The disorganized minerals become more organized.
Foliation
The disorganized minerals become more organized.

8. Weak areas are prone to breakage.
Cleavage
Weak areas are prone to breakage.

9. Weathering and Erosion
Types of Rocks
Very high heat melts metamorphic rock into magma.
Weathering and erosion will change metamorphic rock back to sediments.
Sediments
Metamorphic Rock
Magma
Weathering and Erosion
Melting

10. Magma (molten rock) A hot liquid made of melted minerals
Called lava when it appears on Earth’s surface, usually from volcanic vents
The temperature of magma can range from 650 to 1200 °C
Created by heating rock under extreme temperatures
Cooling magma creates igneous rock

11. Rock Cycle Igneous Rock Magma Sediments Metamorphic Rock
Cooling
Weathering and Erosion
Magma
Sediments
What do weathering and erosion do to all types of rock?
What does melting metamorphic rock create?
Which rock becomes metamorphic rock under heat and pressure?
What do heat and pressure to do sedimentary rock?
What does cooling magma create?
What do compaction and cementation do to sediments?
What do weathering and erosion do to this type of rock?
What does the melting of igneous rock create?
Melting
Cementation
Metamorphic Rock
Sedimentary Rock
Heat and Pressure

12. Minerals Rocks are made up of one or more types of minerals.
True minerals have the following characteristics:
Solid
Have a crystal structure
Inorganic and naturally occuring
Defined chemical composition

13. Minerals Ways to classify minerals: Hardness: how hard the material is
Luster: how the surface interacts with light
Metallic: metallic qualities such as reflectivity
Color: what color the material is
Magnetism: the rock’s ability to attract other metals
Fluorescence: appearance under UV light

14. Erosion
Erosion is the movement of particles by wind, water, ice, or gravity.
Erosion is a natural process that can be increased by human land use.
Steep slopes, lack of vegetation, and land use can increase the rate of erosion.
How does erosion differ from weathering?
Weathering-If a rock is mechanically or chemically loosened but does not move, it is called weathering.
Erosion-If the sediments that were loosened due to weathering are actually moved from one location to another, it is called erosion.

15. Erosion

16. Erosion Types of erosion include:
Gravity erosion
Water erosion
Shoreline erosion
Ice erosion
Wind erosion
Can you explain what occurs in each of these types of erosion?
Gravity erosion is usually caused by steep slopes that pull gravel and dirt downhill. Water erosion is caused by rivers moving sediments and rain, sometimes ending in mudslides. Shoreline erosion is caused by the tide and constant bombardment of waves. This washes away sediment, degrading the coast. Ice erosion is caused by movement of ice such as glaciers scraping down rock and carrying it elsewhere. Wind erosion is caused by the wind, both constant weak winds and strong coastal winds.