1. 3 Major Rock Groups

2. 3 Major (Geologic) Rock Groups Igneous Rock Sedimentary Rock Metamorphic Rock

3. Identifying Rocks Igneous pattern Metamorphic patternSedimentary pattern

4. A. Igneous Rock - Forms when hot, liquid, rock crystallizes (cools and solidifies). Magma forms 3 ways: 1. Rock is heated 2. Pressure released 3. Change composition Basalt lava (glowing rock) oozes over basalt lava flow Holt Online Visual: Comparing Int. & Ext Igneous Rocks

5. a. Intrusive Igneous Rock -Forms inside Earth -slow cooling

7. b. Extrusive Igneous Rock -Forms on surface (exterior) of Earth -Fast cooling

8. Felsic Rock -Light colored -made of aluminum, potassium, silicon, and sodium. Mafic Rock -Dark colored -Made of calcium, iron, and magnesium. Course-grained Fine-grained Course-grained Fine-grained a. Composition of Igneous Rock

9. b. Texture of Igneous Rock -Slow cooling forms large crystals. (Coarse-grained Texture) -Fast cooling forms small crystals. (Fine- grained Texture)

10. -Rate of cooling influences crystal size. Fast cooling = small crystals Slow cooling = large crystals Show Holt Visual: Igneous Rock Texture

12. Rock ID practice Use the rock key to identify the various rocks on your table: Igneous Rocks Classified according to two qualities or traits: composition & texture. Glassy- shiny and looks like glass, not organized into crystals. Ex: obsidian

13. Fine-grained-made of interlocking crystals. Ex: basalt BASALT

14. More Igneous Rocks… Course Grained Texture- Granite

15. More Igneous Rocks… Porous- no crystals, cools rapidly, looks like a sponge. Ex: pumice

16. Diffferent size crystals locked together More Igneous Rocks…

18. Igneous Rock Pop Quiz! Answer these in your NB 1. What size crystal forms from extrusive rock? 2. What is one way magma forms? 3. Generally speaking what color are felsic rocks? 4. Quality (trait) of a rock based on the size, shape, and arrangement of grains is shape, and arrangement of grains is referred to as its… ( See slide #12 ) referred to as its… ( See slide #12 ) 5. What are the 2 characteristics that geologists study to classify & identify rocks? study to classify & identify rocks?

19. Sedimentary Rock Strata layers of rock. Stratification The process in which sedimentary rocks are arranged in layers. Holt Visual Sedimentary Rock Cycle

20. 3 Types of Sedimentary Rock 1. Clastic forms when rock or mineral fragments are cemented together.

21. 2. Chemical forms when minerals crystallize out of solution, such as sea water, to become rock.

22. 3. Organic forms from the remains of once-living plants and animals. Ex: Limestone Coal Coal Chalk Chalk

23. Sedimentary Pop Quiz Make 5 questions of your own in your NB Put the answers on the back side of your quiz page 1. 1. 2. 2. 3. 3. 4. 4. 5. 5.

24. Metamorphic Rock -Rocks that have undergone a change in texture, structure, or composition. -Changes in heat and pressure cause rocks to change from one form to another.

26. Origins of Metamorphic Rock

27. Contact Metamorphism Contact Metamorphism Rock undergoes metamorphism when it comes in contact with magma or is heated by nearby magma. Rock undergoes metamorphism when it comes in contact with magma or is heated by nearby magma.

28. Regional Metamorphism -Pressure builds up in rock that is buried deep below rock formations or when large pieces of rock collide.

29. Textures of Metamorphic Rock Foliated the texture of metamorphic rock in which the mineral grains are arranged in planes or bands.

30. Nonfoliated -The texture of metamorphic rock in which the mineral grains are not arranged in planes or bands.

31. Metamorphic Pop Quiz Make 5 questions of your own in your NB Put the answers on the back side of your quiz page 1. 1. 2. 2. 3. 3. 4. 4. 5. 5.