1. Granite is a mixture of:
Rocks
Granite is a mixture of:
Feldspar
Quartz
Mica
Hornblende
Combinations of
different minerals

2. Rocks Rocks are made up of a mixture of minerals:
1. They can be formed in many different ways.
2. Rocks come in many different shapes and colors.
3. The components are not in any fixed proportion.

3. Types of Rocks
Igneous
Sedimentary
Metamorphic

4. The Rock Cycle
Model that shows how one kind of rock changes into another kind of rock.
The diagram of the rock cycle shows how the earth's rocks are changed again and again.
Has no beginning and no end, rocks are continually changing from one form to another.
The changes that take place in the rock cycle never destroy or create matter. The elements are just distributed in other forms.

7. Heat and Pressure
Weathering, Erosion, and Deposition
Compaction and Cementation
Cooling and Crystallization
Melting
Heat and
Pressure
Sedimentary Rock
Metamorphic Rock
Igneous Rock
Sediment
Magma

8. Rocks are changed by processes such as:
Weathering
Erosion
Deposition
Compaction
Cementation
Crystallization
Heat and Pressure
Melting

9. Weathering
The breaking down of solid rock by chemical or physical forces.
Results in small particles and/or new chemicals.
Example:
- Physical change – Some of the mineral matter in mountains is broken off by wind, water, or ice but otherwise remains the same.
- Chemical change – Some of the mineral matter is carried away in streams as individual particles we cannot see. These particles are free to react with other particles to produce new minerals.

10. Erosion
When weathered particles are carried (transported) by agents of erosion, such as wind, water, ice, or gravity.

11. Deposition
When weathered material is laid down, generally in layers, in a new location.

12. Compaction
When deposited particles are compressed into smaller volume.

13. Cementation
When the deposited particles are “glued” together by a cementing agent or by pressure.

14. Crystallization
When liquid rock (magma or lava) freezes into a solid form.

15. Heat and pressure
Created by deep burial or by close contact with molten rock (lava or magma).

16. Melting
Changing a solid into a liquid by heat/pressure.

18. Igneous Rocks The most abundant type of rock on Earth.
Most igneous rocks are produced deep underground by the cooling and hardening of magma.

19. Classification of Igneous Rocks
Classified according to how the magma cools and hardens (crystallizes).
Composition-refers to the minerals that make up the rock.
Texture-shape, size, arrangement and distribution of minerals that make up the rock.

20. Composition Extrusive- Formed from lava; volcanic
Intrusive- Formed deep within the earth; plutonic
Obsidian
Pumice
Granite

21. Intrusive vs. Extrusive Rocks
Intrusive – Magma solidifies deep within the earth. The slow cooling causes large crystals to form and the texture is coarse-grained.
Think: INside. Formed inside the earth.
Extrusive – Magma flows to the surface (now called lava) and cools very rapidly. This rapid cooling causes small or no crystals to form and the texture is fine-grained.
Think: EXit. These rocks exited the Earth

22. Textures Coarse-grained Glassy Porphyritic Fine-grained Obsidian
Granite
Basalt
Granite

23. Gabbro vs. Basalt
Diorite vs. Andesite
Granite vs. Rhyolite

24. Sedimentary Rocks
Forms from cementing together of Earth’s materials called sediment (clay, sand, pebbles, gravel, plants or animal remains).
75% of the rocks at Earth’s surface are sedimentary rocks.
Sedimentary rocks can be categorized into three groups based on sediment type.

25. Clastics
Clastic rocks are composed of grains or fragments of rocks and minerals that have been eroded, transported, deposited, and cemented together.
During the transport process, the particles that make up these rocks often become rounded due to abrasion or can become highly sorted.

26. Non-clastics
Non-clastic rocks are created either from chemical precipitation and crystallization, or by the lithification of once living organic matter.
Identification of non-clastics requires identification of the primary mineral.

27. Classification of Sedimentary Rocks
Clastic (fragmental) – formed from the broken pieces of other rocks (clastics).
Organic – forms from accumulation of dead plants and animals.
Chemical – form when dissolved minerals precipitate out or are left behind when a solution evaporates.

28. Clastic Rocks
Conglomerate
Sandstone
Shale

29. Organic Rocks Organic rock comes remains of plants and animals
Coquina
Fossiliferous Limestone

30. Chemical Rocks Chemical rocks come from minerals that are dissolved in a solution and crystallize
Limestone

31. Metamorphic Rocks
Formed when high heat and pressure changes the original or parent rock into a completely new rock.
The parent rock can be either sedimentary, igneous, or even another metamorphic rock.

32. Metamorphic Rocks Metamorphic means “change in form”. Two categories:
Regional Metamorphism – the deeper a layer of rock lies within the earth’s crust, the more it will be affected by temp and pressure.
Contact Metamorphism – common in regions of volcanic activity since hot magma may heat the preexisting rock layers.

33. Foliated When mineral grains flatten and line up in parallel layers.
Light and dark bands.

34. Unfoliated The mineral grains change, grow and rearrange but they
don’t form bands.