Buildings

Roads

Bridges

Concrete

Extract minerals – like iron (Fe) to make steel

Toothpaste

Salt

Sandpaper

Decorations

Jewelry

1. Why is it important to have a basic 1. Why is it important to have a basic understanding of the rock cycle?understanding of the rock cycle?

Rocks contain clues about the environment. Helps us understand the formation of the earth.

2. Rock2. RockAny solid mass of minerals or mineral-like matter

3. Do most rocks occur as one 3. Do most rocks occur as one mineral or as a mixture of minerals?mineral or as a mixture of minerals?

4. Some rocks are made of non-4. Some rocks are made of non-mineral material, can you name one?mineral material, can you name one?

Coal - begins as layers of plant matter accumulate at the bottom of a body of water. For the process to continue the plant matter must be protected from biodegradation and oxidization, usually by mud or acidic water. This trapped atmospheric carbon in the ground in immense peat bogs that eventually were covered over and deeply buried by sediments under which they metamorphosed into coal. Over time, the chemical and physical properties of the plant remains (believed to mainly have been fern-like species antedating more modern plant and tree species) were changed by geological action to create a solid material.

Coal, a fossil fuel, is the largest source of energy for the generation of electricity worldwide.

5. Explain the rock cycle.5. Explain the rock cycle.A continuous process that causes rock to change from one form to another

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The Rock Cycle is a group of changes, this change does not necessarily have to be a chemical change. Igneous rock can change into sedimentary rock or into metamorphic rock. Sedimentary rock can change into metamorphic rock or into igneous rock.Metamorphic rock can change into igneous or sedimentary rock. Almost all of rock today that we have on earth is made up of all the same stuff as the rocks that dinosaurs and other ancient life forms walked, crawled, or swam overWhile the stuff that rocks are made of has stayed the same, the rocks themselves, have notOver time rocks are recycled into other rocksMoving tectonic plates are responsible for destroying and forming many types of rocks

6. List the 3 types of rocks6. List the 3 types of rocks

Igneous rock forms when magma cools and makes crystals. Magma is a hot liquid made of melted minerals. When magma pours onto the earth’s surface it is called lava. The minerals can form crystals when they cool. Igneous rock can form underground, where the magma cools slowly. Or, igneous rock can form above ground, where the magma cools quickly. The crystals grow together and form one igneous rocks.

7. Igneous Rocks7. Igneous Rocks

8. What kind of igneous rocks form when molten lava cools and hardens?

Extrusive = forced out while molten through cracks in the earth's surface

9. What is the Latin word that the word igneous comes from and what does it mean? ignis = fire

10. Intrusive Igneous Rocks10. Intrusive Igneous RocksForm from magma below the earth’s surface

11. Extrusive Igneous RocksFormed by lava on the Earth’s surface

12. What is the difference 12. What is the difference between magma and lava?between magma and lava?

Magma = molten rock below the earth’s surface

Lava = molten rock flowing on the earth’s surface

13. What are the 8 elements that 13. What are the 8 elements that make up magma?make up magma?

Silicon, oxygen, aluminum, iron, calcium, sodium, potassium, magnesium

14. In what ways are the two rocks similar? 14. In what ways are the two rocks similar?

Look at the granite rock (A on age 71) and the rhyolite rock (B on page 71)

Granite Rhyolite

Both are from melted rock

Their composition is the same

15. In what ways are the two rocks different?15. In what ways are the two rocks different?Granite Rhyolite

Granite – coarse texture, made from magma

Rhyolite – fine texture, made from lava

16. What causes the two rocks to be different?16. What causes the two rocks to be different?Granite Rhyolite

Granite – Slow cooling below the earth’s surface

Rhyolite – Quick cooling on the earth’s surface

17. Why do you think some rocks are 17. Why do you think some rocks are heavier than others?heavier than others?

Some are denser – less air space between particles

Which rock would have greater density?Which rock would have greater density?

Pumice Granite

Classifying RocksClassifying Rocks

Rocks can be classified, or put into groups with similar characteristics, by looking at the rocks texture, mineral composition, and color.

18. What is texture?The size, shape, and pattern of the rock’s grain

(nice)

Glassy

The minerals that make up the different parts of a rock

19. Composition (what’s it made of?)19. Composition (what’s it made of?)

Examples:QuartzFeldsparMagnesiumIron

ADDADD

Rock ColorRock ColorThe apparent color of the rock, on the inside and the outside

20. Slow cooling magma will form 20. Slow cooling magma will form rocks with arocks with a

a. coarse grained texture.a. coarse grained texture.b. fine grained texture.b. fine grained texture.c. glassy texture.c. glassy texture.d. porphyritic texture.d. porphyritic texture.

21.21. Rapid cooling magma will form Rapid cooling magma will form rocks with arocks with a

a. coarse grained texture.a. coarse grained texture. b. fine grained texture.b. fine grained texture. c. glassy texture.c. glassy texture. d. porphyritic texture.d. porphyritic texture.

22. When lava spews onto the earth’s 22. When lava spews onto the earth’s surface rocks will form with asurface rocks will form with aa. coarse grained texture.a. coarse grained texture.b. fine grained texture.b. fine grained texture.c. glassy texture.c. glassy texture.d. porphyritic texture.d. porphyritic texture.

23. Magma that is located deep 23. Magma that is located deep within the earth may take tens of within the earth may take tens of thousands of years to harden.thousands of years to harden.The rocks that form in this case The rocks that form in this case will have awill have a

a. coarse grained texture.a. coarse grained texture.b. fine grained texture.b. fine grained texture.c. glassy texture.c. glassy texture.d. porphyritic texture.d. porphyritic texture.

24. Which 2 minerals are granitic 24. Which 2 minerals are granitic rocks composed of?rocks composed of?

Quartz

Feldspar

25. Which 2 minerals are basaltic 25. Which 2 minerals are basaltic rocks composed of?rocks composed of?

Magnesium

Iron

Metamorphic rocks are rocks that have "morphed" into another kind of rock. These rocks were once igneous or sedimentary rocks. How do sedimentary and igneous rocks change? The rocks are under tons and tons of pressure, which fosters heat build up, and this causes them to change. If you exam metamorphic rock samples closely, you'll discover how flattened some of the grains in the rock are.

Rock divisions occur in three major families based on how they formed: igneous, sedimentary, and metamorphic. Each group contains a collection of rock types that differ from each other on the basis of the size, shape, and arrangement of mineral grains.Just remember 3 types of rocks=3 divisions. (igneous, sedimentary, and metamorphic)

When classifying a rock sample geologists observe the rock’s color and texture and determine its mineral composition.Texture: the size, shape, and pattern of the rock’s grain.Color: the apparent color of the rock, on the inside and the outside.Mineral composition: The minerals that make up the different parts of a rock.

Texture: Grain Size

Often, the grains in a rock are large and easy to see. Such rocks are said to be coarse-grained. In other rocks, the grains are so small that they can only be seen with a microscope. These rocks are said to be fine-grained. Notice the difference in texture between the fine-grained slate and the coarse-grained diorite to the right.

Texture: Grain Shape

• The grains in a rock vary widely in shape• Some grains look like tiny particles of fine sand• Others look like small seeds or exploding stars• In some rocks, such as granite, the grain results from the

shapes of the crystals that form the rock• In other rocks, the grain shape results from fragments of

other rock• These fragments can be smooth and rounded, like the

fragments in conglomerate, or they can be jagged, like the fragments in breccia

• You can compare conglomerate and breccia one the next slide

Texture : Grain Pattern

• The grains in a rock often form patterns. Some grains lie in flat layers that look like a stack of pancakes.

• Other grains form wavy, swirling patterns. Some rocks have grains that look like rows of multicolored beads, as in the sample of gneiss shown above.

• Other rocks, in contrast, have grains that occur randomly throughout the rock.

Different Types of Texture

Fine-Grained, Coarse-Grained, Rounded Grain, Jagged Grain, Nonbanded, Banded

INTRUSIVE IGNEOUS ROCKS – When igneous rocks are formed by magma that cools BENEATH Earth’s surface, they are called intrusive igneous rocksEXTUSIVE IGNEOUS ROCKS – When igneous rocks are formed by LAVA ON Earth’s surface, they are called extrusive igneous rocks

2 Types of Igneous Rocks

• The process by which sediment becomes sedimentary rock

• 1st step : erosion• 2nd step : deposition• 3rd step : compaction• 4th step : cementation

Lithification

Sedimentary Rocks : Erosion

Destructive forces are constantly breaking up and wearing away all the rocks on Earth’s surfaceThe forces include heat and cold, rain, waves, and grinding iceErosion occurs when running water or wind loosens and carry away the fragments of rock.

Sedimentary Rocks: Deposition  Eventually, the moving water or wind slows and deposits the sediment. If water is carrying the sediment, rock fragments and other materials sink to the bottom of a lake or ocean. Deposition is the process by which sediment settles out of the water or wind carrying it. After sediment has been deposited, the processes of compaction and cementation change the sediment into sedimentary rock. In addition to particles of rock, sediment may include shells, bones, leaves, stems, and other remains of living things. Over time, any remains of living things in the sediment may slowly harden and change into fossils trapped in the rock.

Sedimentary Rocks: Compaction

 At first the sediments fit together loosely. But gradually, over millions of years, thick layers of sediment build up. These layers are heavy and press down on the layers beneath them. Then compaction occurs. Compaction is the process that presses sediments together. Year after year more sediment falls on top, creating new layers. The weight of the layers further compacts the sediments, squeezing them tightly together. The layers often remain visible in the sedimentary rock.

 While compaction is taking place, the minerals in the rock slowly dissolve in the water. The dissolved minerals seep into the spaces between particles of sediment. Cementation is the process in which dissolved minerals crystallize and glue particles of sediment together. It often takes millions of years for compaction and cementation to transform loose sediments into solid sedimentary rock.

Sedimentary Rocks: Cementation

Point A: water or wind deposits sedimentsPoint B: The heavy sediments press down on the layers beneathPoint C: Dissolved minerals flow between the particles and cement them together

Sedimentary Transformations

Metamorphic Rock Pictures

Granite, Gneiss, Shale, Slate, Sandstone, and Quartzite are good examples of metamorphic rocks.

Bet Cha’ Weren’t Expecting A….POP QUIZ!!!!!*

1. What are the three types of rock?2. Which type of rock has been formed by

magma or lava?3. What do we classify rocks by?4. How do sedimentary rocks form (in order)?5. Metamorphic rocks are rocks that have

?(fill in the blank)6. What is the process of sediments forming a

sedimentary rock? 7. What does “ignis” mean in the word igneous?

*Answers are on next slide!

ANSWERS!!!!

1. Igneous, Sedimentary, and Metamorphic2. Igneous3. Texture, Color, and Mineral Composition4. Erosion, Deposition, Compaction,

Cementation5. Morphed6. Lithification7. “ignis” means fire

www.dlese.com

Earth Science TextbookGoogle Images ( I KNOW THIS DOESN’T COUNT IM JUST TELLING YOU!!)http://www.rocksandminerals.com/rockcycle.htm

Sedimentary rocks form from particles deposited by water and windIf you have ever walked along a beach (which I am sure you have) you may have noticed tiny sand grains, mud, and pebbles.These are some sediments that eventually form into sedimentary rocksSedimentary Rocks can form in 4 ways by:ErosionDepositionCompactionCementation