Inside EarthChapter 5RocksReview and Reinforce WorksheetAnswer Keys
Section 5-1 Review and Reinforce(p. 129)1. Coarse-grained2. Very small3. Shape4. Pattern5. Glassy6. Geologists observe the rock’s color and textureand determine its mineral composition.7. Igneous rock forms from the cooling ofmolten rock. Sedimentary rock forms whenparticles of other rocks or the remains ofplants and animals are pressed and cementedtogether.Metamorphic rock forms when anexisting rock is changed by heat, pressure, orchemical reactions.8. Geologists use the scratch test, a test with anacid to determine whether the rock containsthe mineral calcite, and a magnet test.9. texture10. grains
Section 5-2 Review and Reinforce (p. 133) 1. Coarse-grained 2. Porphyritic 3. Glassy 4. Fine-grained 5. Lava that is low in silica usually forms darkcolored rocks; magma that is high in silica usually forms light-colored rocks. 6. Igneous rocks are hard, dense, and durable. 7. Answers may vary. A typical answer might mention granite as a building material, basalt as a construction gravel, and pumice as an abrasive in polishes. 8. extrusive 9. porphyritic 10. intrusive
Section 5-3 Review and Reinforce(p. 137)1. b, d, a, c2. Clastic3. Organic4. Clastic5. Chemical6. Organic7. Clastic8. Chemical9. Clastic10. d11. f12. a13. e14. c15. b16. h17. g
Section 5-5 Review and Reinforce (p. 145)1. mantle2. pressure3. mineral crystals4. Pockets of magma rising the rough Earth’s crustcan provide heat that can produce metamorphic rocks.5. Geologists classify metamorphic rocks by the arrangement of the grains that make up the rocks.6. Quartzite forms when weakly cemented quartzparticles in sandstone recrystallize.7. Marble has a fine, even grain; it is relatively easy to cut into thin slabs; and it can be easily polished.8. Nonfoliated9. Foliated10. Foliated
Section 5-6 Review and Reinforce (p. 149)1. Igneous rock 2. Sedimentary rock 3. Pressure4. Metamorphic rock 5. Magma6. Constructive forces move rock through the rock cycle by making new igneous rock or building up Earth’s surface. Destructive forces move rock through the rock cycle when erosion begins the process of forming sedimentary rock or when subduction causes part of the crust to sink into the mantle.7. Answers will vary. Students might describe any pathway that changes one type of rock into another.8. Water and weather wear away the granite of the mountain, and sand grains from the granite are deposited on the ocean floor, wherecompaction and cementation change them to sandstone. If the sandstone is pushed deeper into the crust, heat and pressure change it into quartzite.9. Plate movements push rocks back into the mantle, where they melt and become magma. They also cause the folding, faulting, anduplift of the crust.10. Answers will vary. Sample answer: The rock cycle is the slow changing of rocks from one kind to another by the constructive anddestructive forces on and below Earth’s surface.