Name: ______________________ Class: _________________ Date: _________

Chapter 6 Review Test Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. ____

1. According to uniformitarianism, how does geologic change happen? a. every few years c. gradually b. suddenly d. after an earthquake

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2. Which of the following events would be a catastrophe? a. an average rainfall c. gradual erosion b. an asteroid hitting the earth d. deposition

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3. What kind of scientist studies the history of plants and animals? a. a paleontologist c. a geologist b. a botanist d. a chemist

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4. What does a paleobotanist study? a. vertebrate animals b. invertebrate animals

c. fossilized insects d. fossil plants

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5. How are rock layers arranged in the geologic column? a. Youngest rocks are in the middle. c. Oldest rocks are on the bottom. b. Youngest rocks are on the bottom. d. Oldest rocks are on the top.

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6. What is a fault? a. molten rock that squeezes into existing rock b. a break in the Earth’s crust c. slanted layers of rock d. a bent and buckled layer of rock

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7. What is the most common type of unconformity? a. a disconformity c. a nonconformity b. an angular unconformity d. a fault

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8. Which of the following are isotopes? a. atoms with the same number of protons and neutrons b. atoms with the same number of neutrons c. atoms with the same number of protons but a different number of neutrons d. atoms with the same number of electrons

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9. What does a scientist need to know to figure out the absolute age of a rock? a. the rate of decay for all elements in the rock b. the rate of decay for a radioactive element in the rock c. the rate of superposition for a radioactive element in the rock d. the rate of decay of the rock’s half-life

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ID: A

Name: ______________________

ID: A

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10. Which two methods of radiometric dating are used for rocks more than 10 million years old? a. rubidium-strontium and uranium-lead b. rubidium-strontium and potassium-argon c. rubidium-strontium and carbon-14 d. rubidium-strontium and carbon-12

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11. What is amber? a. a hard shell b. hardened tree sap

c. an insect’s body d. wet, sticky tree sap

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12. Which of the following is an example of mineral replacement? a. La Brea asphalt c. hardened tree sap b. a frozen mammoth d. petrified wood

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13. Which of the following is an example of a trace fossil? a. preserved footprints c. hardened tree sap b. mold and cast d. a frozen mammoth

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14. Which kind of temperatures will slow down an organism’s decay? a. warm temperatures in a wet climate c. freezing temperatures b. cool temperatures d. hot temperatures

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15. Which era ended with the largest mass extinction in Earth’s history? a. Paleozoic c. Cenozoic b. Mesozoic d. Jurassic

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16. During which era did birds and small mammals begin to evolve? a. Paleozoic c. Cenozoic b. Mesozoic d. Jurassic

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17. Which era are we in now? a. Paleozoic b. Mesozoic

c. Cenozoic d. Jurassic

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18. What does the rock and fossil record represent? a. index fossils c. the Age of Reptiles b. geologic time d. the Age of Mammals

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19. If a trilobite were buried by ocean sediment, it would leave a cavity, or a(n) a. trace fossil. c. cast. b. mold. d. index fossil.

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20. Which of the following is the largest division of geologic time? a. eon c. era b. epoch d. period

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21. Erosion is one of the major causes of the missing rock layers, known as a. superposition. c. the geologic column. b. unconformities. d. tilting.

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Name: ______________________

ID: A

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22. A fossil used to date surrounding rock layers is called a(n) a. index fossil. c. cast. b. mold. d. trace fossil.

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23. To determine the most accurate and precise age of Earth’s oldest rocks, geologists would use a. relative dating. c. the carbon-14 method. b. the uranium-lead method. d. index fossils.

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24. Which of the following is a trace fossil? a. a mark left by a dinosaur’s tail b. a mosquito trapped in amber

c. a mummified plant seed d. a frozen woolly mammoth

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25. How many years of the history of Earth do geologists study? a. 5,000 years c. 2.5 million years b. 1,000 years d. 4.6 billion years

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26. The phrase “younger over older” could be used to remember the principle of a. absolute dating. c. unconformities. b. geologic columns. d. superposition.

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27. What did marine fossils discovered on a Canadian mountaintop tell scientists? a. Marine species once lived on land. b. The rocks on the mountaintop were once below the ocean’s surface. c. The rocks had probably been preserved in amber. d. The rocks had probably eroded.

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28. Which of the following do geologists use to date rock layers? a. trace fossils c. index fossils b. molds d. casts

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29. What is tilting? a. an intrusion b. a form of erosion

c. folding of rock layers d. slanting of rock layers

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30. Which word best describes the geologic column? a. relative c. absolute b. ideal d. complete

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31. What do scientists think may have caused dinosaurs to become extinct? a. climate change c. disappearance of prey b. competition from mammals d. competition between dinosaurs

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32. What happens during radioactive decay? a. Isotopes become radioactive. b. Stable isotopes become unstable isotopes. c. Radioactive isotopes break down into stable isotopes of other elements. d. Radioactive isotopes break down into unstable isotopes.

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Name: ______________________

ID: A

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33. How do geologists use the geologic time scale? a. to divide Earth’s history into manageable parts b. to date rock layers c. to predict future extinction events d. to record catastrophes

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34. What can animal tracks tell about the animal that left them? a. what the animal ate c. its color b. how big it was d. its mating habits

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35. What can a scientist learn from studying the relationships between fossils? a. how paleontology has changed c. how science has changed b. how life has changed d. how the geologic column has changed

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36. What would geologists use to determine the most accurate and precise age of Earth’s oldest rocks? a. relative dating c. the carbon-14 method b. the uranium-lead method d. index fossils

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37. Which of the following processes always occurs at a constant rate? a. erosion c. sediment deposition b. decay of organic matter d. radioactive decay

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38. Global climate change may have caused the extinction of which group of animals? a. birds c. dinosaurs b. mammals d. insects

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39. What process compares one rock layer with others in a sequence? a. radioactive decay c. relative dating b. radiometric dating d. absolute dating

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40. Molten rock that squeezes into existing rock and cools is called what? a. folding c. intrusion b. fault d. tilting

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41. Which of the following is NOT a measure of absolute dating? a. uranium-lead c. carbon-12 b. strontium-rubidium d. potassium-argon

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42. What do scientists know about an undisturbed sequence of rocks? a. Older rocks are on top of younger rocks. b. Younger rocks are on top of older rocks. c. Younger rocks are under older rocks. d. Older rocks have eroded away.

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43. How does the geologic column help geologists? a. It helps them find water. c. It helps them identify rock layers. b. It tells them where to find trace fossils. d. It isn’t much help at all.

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44. Where are most fossils preserved? a. in ice b. in amber

c. in sedimentary rock d. in asphalt

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Name: ______________________

ID: A

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45. Why is the fossil record incomplete? a. Most organisms never became fossils. c. There isn’t enough asphalt. b. Scientists don’t like to work on it. d. There isn’t enough amber.

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46. As long as a sequence of rock layers is undisturbed, what can scientists know about it for certain? a. No one has been there before. b. Older rocks are on top of the sequence. c. Younger rocks are on top of the sequence. d. All of the rocks are the same age.

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47. Which method is most useful in dating the remains of plants and animals that lived within the last 50,000 years? a. uranium-lead c. rubidium-strontium b. potassium-argon d. carbon-14

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48. Which part of an animal is more commonly preserved? a. the eyes c. the shell or bones b. the soft parts d. the organs

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49. How old would rock surrounding a Tropites fossil be? a. about 210 million years old c. nearly 4.6 billion years old b. about 47 million years old d. less than 100,000 years old

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50. Which of the following can scientists NOT interpret by examining fossils? a. how Earth’s environment has changed over time b. how plants and animals have changed over time c. the age of certain layers of rocks d. how the pull of gravity has changed

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