Chapter 4 Rocks: Mineral Mixtures

1. Chapter 4Rocks: Mineral Mixtures Standard S6E5.b Investigate the composition of rocks in terms of minerals

2. Section 1 pp.90, 95, 96 EQ: How are rocks and minerals different? • Rock • Naturally occurring solid mixture of one or more minerals and organic (living) matter

3. 3 Classes of Rocks Igneous Sedimentary Metamorphic EQ: How are rocks classified?

4. Composition Texture The chemical makeup of the rock –the minerals and other materials The size, shape and positions of the rock grains Provides clues as to how and where the rock is formed Rocks are classified by:

5. Summary • Write a paragraph that: • Compares and contrasts minerals and rocks. • Write another paragraph that: • Compares and contrasts composition and texture.

6. Igneous Rocks Igneous means “fire” Begins as magma that contains many minerals Cooled magma hardens and solidifies Section 2 pp.98 – 101EQ: Where do igneous rocks come from?

7. Composition of Igneous Rocks Determined by minerals Light colored ones – less dense– made of aluminum, silicon Dark colored ones – more dense, made of iron, calcium, & magnesium

8. Texture of Igneous Rocks Size of the grains Fast cooling lava on the surface of the volcano -- fine grains or no grains Ex: pumice Slow cooling magma inside the Earth -- large grains Ex: granite

9. Igneous Rock Formation Intrussive igneous rock -- forms inside Earth cools slowly large grains Ex: granite

10. Igneous Rock Formation Extrussive Igneous Rock -- forms on Earth’s surface cools fast fine grains or no grains Ex: pumice

11. Igneous Rock Formation In other words, the faster the magma or lava cools the smaller the grains of the rock The slower the magma or lava cools the larger the grains of the rock

12. Summary • Compare and contrast Stone Mountain’s granite and pumice from a volcano.

13. Draw a Picture of the Formation of Igneous Rocks • Label intrusive, extrusive, magma, lava. • Show the grain size of the developing rocks. • Indicate how fast the rocks cool. • Name rock samples for each class of igneous rocks.

14. Sediment Fragments of weathered rock & minerals Section 3 pp. 102 – 105EQ: What are sedimentary rocks made of?

15. Strata Layers of sed. rock on Earth’s surface that forms when the sed is deposited & cemented together by dissolved clacite & quartz

16. Stratification Process in which sed. Rocks are arranged in layers

17. Clastic Made of rock fragments cemented together by dissolved calcite & quartz May be any grain size Examples: conglomerate, shale, sandstone EQ: What are the 3 classes of sedimentary rock?

18. Chemical From solutions of dissolved minerals in water The dissolved minerals crystallize Ex: halite—salt—NaCl Result of supersaturated salt water

19. Organic Made from the remains of dead organisms Ex: Chalk is made of tiny sea creatures Ex: Coal forms underground when decomposed plant material is changed into coal by heat & pressure Fossil fuels are non-renewable resources

20. Summary • Describe the formation of the 3 classes of sedimentary rock. • Draw a picture of how each sed. rock forms • Show the rock “before” it became a sed. rock and the “after” or the resulting sed. rock. • Label each class of sedimentary rock.

21. Compare and Contrast Igneous and Sedimentary Rocks

22. Metamorphism Metamorphic Rock Change shape The structure, texture or composition of the rock changes because of extreme heat and/or pressure A chemical change occurs Section 4 pp. 106 – 111EQ: What is metamorphism?

23. Deformation Change in the shape of a rock caused by a force, like squeeze or stretch

24. Foliated Non-foliated Mineral grains are arranged in bands Ex: mica, slate Random arrangement of grains Ex: marble EQ: What are the 2 classes of metamorphic rock?

25. Summary • If I needed to make a tool from a rock, should I choose a foliated or a non-foliated metamorphic rock? Explain your answer.