1. Earth Science: Rocks and Minerals (20:00 min)
Minerals & Rocks
Earth Science: Rocks and Minerals
(20:00 min)

2. Minerals
Minerals are pure substances made up of only one type of matter through the process of crystallization.
Crystallization is the process by which atoms are arranged to form a material with a crystal structure.
melted materials (magma or lava)
Deep Magma = slow cooling & large crystals
Shallow Magma = faster cooling & small crystals
Lava = fastest cooling & no crystals
materials dissolved in water
Calcite – weathering from carbon dioxide.

3. Characteristics of Minerals
Are naturally occurring
Cannot be man made
Inorganic
Cannot come from something once living
Definite chemical composition
Element = single atom.
Gold (Au), Silver (Ag), Iron (Fe)
Compound = two or more elements combined.
Calcite (CaCO3), Talc (Mg3Si4O10(OH)2)

5. Identifying Minerals
Each mineral has its own specific property used to identify it:
Hardness
The resistance of a mineral to being scratched.
Mohs Hardness Scale:
1 = softest (Talc), 10 = hardest (Diamond)

6. Porcelain Streak Plate (6.5-7)
selenite
Fingernail (2-3)
Copper Strip (3)
Glass Plate (5.5-6)
microline
Porcelain Streak Plate (6.5-7) 9

7. Identifying Minerals 2. Streak
The color of the powder left after being rubbed on a tile.

8. Identifying Minerals 3. Luster
The ability of a mineral to shine or reflect light.
Metallic
Dull
Pearly
Vitreous

9. Identifying Minerals 4. Cleavage
The tendency of a mineral to break along regular surfaces in one or more specific directions.

10. What is a Rock? A mixture of minerals and other materials.
Granite = quartz, feldspar, mica and hornblende.
Geologists study and classify rocks based on:
Color
Texture
Mineral composition

11. Texture Texture is look and feel of the rock’s surface.
Grains give a rock its texture.
Grain Size: coarse, fine or no visible grains
Grain Shape: Rounded, jagged
Grain Pattern: Banded or non-banded.

12. Rock Types 3 Major groups of rocks: Igneous Rock
Come from the cooling and crystallization of extremely hot liquid rock (lava or magma)
Slow cooling = large crystals
Rapid cooling = small crystals
Extra-fast cooling = no crystals
First rock type to have formed on Earth
“Igneous” = Greek for “fire”

13. Classifying Igneous Rocks
Origin
Extrusive – lava cooling at Earth’s surface
Intrusive – Magma cooling within Earth’s crust.
Texture
Fine grained – rapid cooling
coarse grained – slow cooling
Mineral Composition
Mafic (Iron & Magnesium)
dark colored
Felsic (Aluminum)
light colored

15. Rock Types 2. Sedimentary Rock
Particles of rocks or remains of plants and animals that are compacted and cemented together.
Deposited in layers by water, wind and ice.
Classified into 3 groups based on how they were made:
Organic – formed from remains of living things; plants and animals
Chemical – formed when elements dissolved in water came out of solution.
Clastic – formed when particles that were weathered from other rocks were cemented together.

16. Shell Limestone

17. Rock Types 3. Metamorphic Rocks – “Changed Rock” Two texture groups:
When existing rock; sedimentary, igneous or metamorphic, has its texture, structure and composition changed by heat, pressure or chemical reactions.
Two texture groups:
Foliated – platy or leaf-like minerals (mica or chlorite) are nearly aligned parallel to one another.
Splits along well-oriented, parallel lines
Non-foliated – randomly oriented platy minerals, massive.
Break into angular pieces

19. The Rock Cycle Plate Tectonics
A series of processes on Earth’s surface and inside the planet that slowly change rocks from one kind to another = rock cycle.
Builds, destroys and changes the rocks in the crust.
What process drives the rock cycle?
Plate Tectonics

20. The Rock Cycle

21. The Rock Cycle Igneous Rock Sedimentary Rock Metamorphic Rock
Rock formed from the cooling of melted rock is called:
Rock formed by weathering and erosion is called:
Rock formed by heat and pressure is called:
Igneous Rock
Sedimentary Rock
Metamorphic Rock