EXAM 1 Review Questions 1. Which of the following statements regarding the scientific method is true? A) A hypothesis must be agreed upon by more than one scientist. B) A theory is a hypothesis that has withstood many scientific tests. C) A theory is proven to be true and therefore may not be discarded. D) A hypothesis cannot predict the outcome of scientific experiments.

2. Which of the following statements about the scientific method is false? A) A scientific theory is never considered finally proved. B) Data used to generate a hypothesis may come from observations, experiments, and chance findings. C) A theory that has accumulated a substantial body of experimental support is called a hypothesis. D) A scientific model represents some aspect of nature based on a set of hypotheses and theories.

3. According to the principle of uniformitarianism, ________. A) geologic processes we observe today have operated in the past B) animals evolved at a uniform rate C) all of the planets formed from a uniform solar nebula D) early Earth was covered by a uniform magma ocean

4. How old is the Earth? A) approximately 4.5 thousand years old B) approximately 4.5 billion years old C) approximately 4.5 million years old D) approximately 4.5 trillion years old

5. The Earth's core is made up primarily of ________. A) iron B) lead C) oxygen D) silicon

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6. Which of the following elements is more abundant in the Earth's crust as compared to the Earth as a whole? A) iron B) magnesium C) nickel D) silicon

7. Which of the following makes up the bulk of the Earth? A) crust B) inner core C) mantle D) outer core

8. Ninety percent of the Earth is made up of which four elements? A) iron, oxygen, silicon, and magnesium B) oxygen, nitrogen, hydrogen, and silicon C) magnesium, aluminum, silicon, and oxygen D) silicon, calcium, aluminum, and iron

9. Approximately 50% of the Earth's crust is made up of which element? A) aluminum B) iron C) oxygen D) silicon

10. What powers the Earth's external heat engine? A) gravitational energy B) radioactive decay C) solar energy D) tidal forces

11. In which of the following subsystems is the Earth's magnetic field generated? A) climate system B) hydrologic system C) geodynamo system D) plate tectonic system

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12. On average, the Earth's lithosphere is approximately ____ km thick. A) 4 B) 20 C) 100 D) 500

13. The asthenosphere is ____________. A) cool and strong B) cool and weak C) hot and strong D) hot and weak

14. What are the plates of plate tectonics made up of? A) asthenosphere B) crust C) lithosphere D) mantle

15. Which of the following relationships is correct? A) asthenosphere = crust B) lithosphere = crust C) asthenosphere = crust + upper mantle D) lithosphere = crust + upper mantle

16. Which of the following statements about convection is true? A) Heat is transferred from hot material to cool material without inducing a flow. B) Hot material flows upward and displaces cool material. C) Cool material flows upward and displaces hot material. D) Random circulation occurs.

17. When did biology's “Big Bang” (evolutionary explosion) occur? A) about 65 million years ago B) about 2.2 billion years ago C) about 540 million years ago D) about 3.5 billion years ago

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18. What caused the mass extinctions 65 million years ago that ended the Age of Dinosaurs? A) major bolide impact B) massive volcanic eruptions C) global glaciation D) all of the above

19. Change in the ground elevation of the Earth's surface is called ________. A) geodesy B) topography C) uniformitarianism D) none of the above

20. The Mohorovicic discontinuity coincides with the __________ boundary. A) mantle-core B) crust-mantle C) lithosphere-mantle D) inner core-outer core

21. Continental crust is ________ oceanic crust. A) less dense than B) the same density as C) more dense than D) Geoscientists have no idea.

22. The Earth's major layers include (from outermost to innermost) ___________. A) inner core, outer core, mantle, crust B) outer core, inner core, mantle, crust C) crust, mantle, outer core, inner core D) crust, outer core, inner core, mantle

23. Magnetic reversals of the Earth's magnetic field are when ____________. A) the Earth's north and south poles flip B) the Earth's magnetic field decreases in intensity C) the Earth's magnetic poles wander D) the Earth's magnetic field increases in intensity

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24. The highest topographic point above sea level on Earth is at ________. A) Mount Himalaya B) Mount Mauna Loa C) Mount Marianas D) Mount Everest 25. The average density of continental crust is ________ g/cm3. A) 2.8 B) 3.4 C) 3.0 D) 4.0

26. Continents float high because they are _______. A) denser than the mantle B) less dense than the mantle C) the same density as the mantle D) thicker than the mantle

27. Which of the following is not an integral part of the scientific method? A) experimentation B) observation C) belief D) criticism

28. The densest part of the Earth is the _______. A) oceanic crust B) continental crust C) mantle D) core

29. Geologist James Hutton advanced the principle of _______. A) uniformitarianism B) uniformity C) conformity D) universalism

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30. The largest jump in density within the Earth is at the _______. A) crust-mantle boundary B) mantle-core boundary C) upper mantle-lower mantle boundary D) outer core-inner core boundary

31. Who proposed the theory of continental drift? A) Charles Darwin B) Harry Hess C) Alfred Wegener D) J. Tuzo Wilson

32. How old are the fossils of the reptile Mesosaurus found in Africa and South America that suggest the two continents were once together? A) about 100 million years old B) about 1.0 billion years old C) about 300 million years old D) about 3.0 billion years old

33. Which of the following is a divergent plate boundary? A) the Andes Mountains B) the Mid-Atlantic Ridge C) the Himalayan Mountains D) the San Andreas fault

34. At what type of plate boundary do the deepest earthquakes occur? A) convergent B) divergent C) transform D) All of these plate boundaries have deep earthquakes.

35. Approximately how deep (below sea level) are the deepest deep-sea trenches? A) 3 km B) 10 km C) 30 km D) 100 km

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36. Which of the following is not associated with convergent plate boundaries? A) earthquakes B) deep-sea trenches C) spreading centers D) volcanoes

37. Which of the following is associated with a divergent plate boundary? A) earthquakes B) volcanism C) rifting D) all of the above

Use the following to answer questions 38-39: Use the following to answer the question(s) below:

38. What type of plate boundary is shown in the diagram? A) a continent collision B) a subduction zone C) a spreading center D) a transform fault

39. Which of the following locations could be represented by the diagram? A) the east coast of Africa B) the west coast of South America C) the east coast of North America D) the west coast of Europe

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40. Which of the following is a type of convergent plate boundary? A) continental rift B) spreading center C) mid-ocean ridge D) subduction zone

41. Which of the following mountain ranges formed as a result of ocean-continent convergence? A) the Andes B) the Appalachians C) the Himalayas D) the Urals

42. When a deep-sea trench is located next to a continent, where would you expect to find active volcanoes? A) on the ocean side of the trench B) in the deep-sea trench C) on the continent side of the trench D) on both the ocean side and continent side of the trench

43. What plate is subducting beneath southwestern Canada and the northwestern United States? A) the Cocos Plate B) the Nazca Plate C) the Juan de Fuca Plate D) the Pacific Plate

44. Which of the following is an example of a transform plate boundary? A) the East African Rift B) the Mid-Atlantic Ridge C) the Marianas Trench D) the San Andreas Fault

45. What type of plate boundary is parallel to the direction of plate movement? A) convergent plate boundary B) transform plate boundary C) divergent plate boundary D) all of the above

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46. Which of the following mountain ranges is the product of continent-continent convergence? A) the Andes B) the Cascade Range C) the Himalayas D) the Japanese islands

47. The North American Plate is bounded by ______ plate boundaries. A) convergent B) transform C) divergent D) convergent, divergent, and transform

Use the following to answer questions 48-49: Use the following to answer the question(s) below: The questions refer to this cross section, which depicts magnetized oceanic crust at a spreading center. The “+” symbol indicates positive (normal) magnetic anomalies; the “–” symbol indicates negative (reverse d) magnetic anomalies.

48. How fast are points C and D spreading apart from each other? A) about 20 millimeters/year B) about 100 millimeters/year C) about 50 millimeters/year D) about 200 millimeters/year

49. “Normal” magnetized crust at the spreading center formed during the ________ epoch. A) Brunhes B) Gauss C) Gilbert D) Matuyama

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50. Modern seafloor spreading rates range from _________. A) 0.2 to 1.5 millimeters per year B) 2 to 15 meters per year C) 2 to 15 centimeters per year D) 2 to 15 kilometers per year

51. What two scientists related the positive and negative magnetic bands on the seafloor to seafloor spreading? A) Charles Darwin and James Hutton B) F.J. Vine and D.H. Mathews C) Harry Hess and Robert Dietz D) Alfred Wegener and Arthur Holmes

52. Which of the following plates is moving the fastest? A) the African Plate B) the North American Plate C) the Eurasian Plate D) the Pacific Plate

53. On a map of the seafloor, the boundaries between normally magnetized oceanic crust and reversely magnetized oceanic crust are called __________. A) dipoles B) isochrons C) isograds D) sutures

54. How old are the oldest rocks on the ocean floor? A) about 20 million years old B) about 600 million years old C) about 200 million years old D) about 4.0 billion years old

55. The oldest continental rocks are __________ than the oldest oceanic rocks. A) much older B) slightly older C) slightly younger D) much younger

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56. Isochrons on the seafloor are roughly __________ the ridge axis along which they were created. A) parallel to and symmetric about B) perpendicular to and symmetric about C) parallel to, but not symmetric about D) perpendicular to, but not symmetric about

57. Why are isochrons on the Pacific seafloor more widely spaced than isochrons on the Atlantic seafloor? A) The Pacific seafloor formed at a faster spreading rate than the Atlantic seafloor. B) The Pacific seafloor formed at a slower spreading rate than the Atlantic seafloor. C) The Pacific seafloor is older than the Atlantic seafloor. D) The Pacific seafloor is younger than the Atlantic seafloor.

58. When did the supercontinent Pangaea begin to break apart? A) about 65 million years ago B) about 570 million years ago C) about 200 million years ago D) about 1.5 billion years ago

59. When did India begin to collide with Asia to form the Himalayas? A) about 50 million years ago B) about 500 million years ago C) about 200 million years ago D) about 2.0 billion years ago

60. What drives plate tectonics? A) magnetic reversals B) mantle convection C) solar energy D) volcanism

61. The Hawaiian volcanoes are __________. A) located at a convergent plate boundary B) located at a divergent plate boundary C) located at a transform plate boundary D) not located at a plate boundary

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62. The Earth's lithosphere is broken up into approximately _____ large plates. A) 5 B) 10 C) 12 D) 20

63. Which of the following locations is least likely to have active volcanoes? A) mid-oceanic ridge B) continental rift valley C) transform fault D) island arc

64. What is limestone made of? A) calcite B) feldspar C) olivine D) quartz

65. Solid materials that do not possess an orderly arrangement of atoms are called _____. A) glasses B) minerals C) crystals D) polymorphs

66. Which of the following substances is not considered a mineral? A) coal B) diamond C) gypsum D) rock salt

67. Isotopes of a given element have __________. A) the same number of protons and the same atomic mass B) the same number of protons but different atomic masses C) different numbers of protons but the same atomic mass D) different numbers of protons and different atomic masses

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68. Which of the following subatomic particles has a positive charge? A) electron B) neutron C) proton D) all of the above 69. Sodium has an atomic number of 11. How many electrons will the sodium ion Na+ have? A) 1 B) 10 C) 11 D) 12

70. Isotopes of an element have different numbers of __________. A) electrons B) neutrons C) protons D) all of the above

71. Carbon has an atomic number of 6 and an atomic weight of 12.011. This means that carbon atoms have __________. A) 6 protons and 12.011 neutrons B) 6 neutrons and 12.011 protons C) 6 protons and a density of 12.011 grams per cubic centimeter D) 6 protons and varying numbers of neutrons

72. The atomic mass of an element is equal to the number of ______. A) protons B) protons plus neutrons C) neutrons D) protons plus neutrons plus electrons

73. What will be the charge of an atom containing 8 protons, 9 neutrons, and 10 electrons? A) –2 B) –1 C) +1 D) +2

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74. How are the elements organized in the periodic table? A) in order of increasing density B) in order of increasing number of electrons C) in order of increasing number of neutrons D) in order of increasing number of protons

75. In order to make a sodium (Na) chlorine (Cl) bond in NaCl, __________. A) one electron is transferred from the chlorine atom to the sodium atom B) one electron is transferred from the sodium atom to the chlorine atom C) two electrons are transferred from the chlorine atom to the sodium atom D) two electrons are transferred from the sodium atom to the chlorine atom

76. What is the dominant type of bonding in minerals? A) covalent bonding B) ionic bonding C) metallic bonding D) nuclear bonding

77. Diamond is an example of what type of bonding? A) covalent B) ionic C) metallic D) nuclear

78. The growth of a solid from a gas or liquid whose atoms can come together in the proper chemical proportions and crystalline arrangement is called ______. A) bonding B) crystallization C) density D) melting

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79. What elements could be represented by the open and solid spheres in the mineral structure depicted below?

A) B) C) D)

carbon and oxygen silicon and oxygen iron and magnesium sodium and chlorine

80. The chemical formula (Mg,Fe)2SiO4 describes which of the following minerals? A) feldspar B) mica C) olivine D) pyroxene

81. Large crystals with well-formed crystal faces tend to form when ____. A) minerals have space to grow B) rocks undergo melting C) molten rock cools quickly D) volcanoes erupt explosively

82. Chemical substances that have exactly the same chemical formula but different crystal structures are called _____. A) electrons B) ions C) isotopes D) polymorphs

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83. Which of the following statements about graphite and diamond is false? A) Graphite and diamond have the same density. B) Graphite and diamond have different mineral structures. C) Graphite and diamond are both made of carbon atoms. D) Graphite is stable in the Earth's crust, whereas diamond is stable in the Earths mantle.

84. What silicate mineral contains tetrahedra linked together as depicted in the diagram below?

A) B) C) D)

amphibole mica pyroxene quartz

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85. Which of the following structures best depicts a silicate ion? (A) (B)

Si

O

Si

O Si

O Si (C)

A) B) C) D)

Si

Si

O (D)

O

O

Si Si

Si O

Si

O

O

O

Si

Si

Diagram A Diagram B Diagram C Diagram D

86. The most common rock-forming minerals in the crust are ______. A) carbonates B) oxides C) silicates D) sulfides

87. The two most common elements in the Earth's crust are _________. A) calcium and carbon B) iron and sulfur C) chlorine and sodium D) oxygen and silicon

88. Which of the following minerals is a common clay mineral used for making pottery? A) feldspar B) kaolinite C) olivine D) pyroxene

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89. Which of the following statements about feldspar is false? A) Feldspar is harder than calcite. B) Feldspar is softer than corundum. C) Feldspar is the most abundant mineral in the Earth's crust. D) Feldspar is a sheet silicate.

90. Which of the following atomic structures represents a carbonate ion?

C

O

O

O

C O

C

C

C O

O

O (B)

(A)

C O

O C

C (C)

A) B) C) D)

C

O

C (D)

Diagram A Diagram B Diagram C Diagram D

91. Which of the following minerals does not contain carbon? A) calcite B) diamond C) dolomite D) gypsum

92. What form of iron is the chief iron ore? A) iron carbonate B) iron oxide C) iron sulfide D) native iron metal

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93. Which of the following minerals fizzes when it comes in contact with hydrochloric acid (HCl)? A) calcite B) halite C) mica D) quartz

94. The mineral property “cleavage” refers to __________. A) the development of crystal faces during mineral growth B) the splitting of a mineral along planar surfaces C) the development of irregular fractures in a mineral D) the density of a mineral

95. Which of the following minerals has two good cleavage planes oriented at right angles to each other? A) amphibole B) calcite C) mica D) pyroxene

96. Which of the following minerals does not exhibit cleavage? A) amphibole B) calcite C) mica D) quartz

97. If hardness is a measure of the strength of chemical bonds, then which of the following minerals has the weakest bonds? A) talc B) mica C) diamond D) graphite

98. Where would you expect to find the largest crystals in a lava flow? A) near the top surface of the flow B) in the center of the flow C) near the bottom surface of the flow D) The crystals would be the same size throughout.

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99. Which of the following properties does not depend on the chemical composition of an igneous rock/magma? A) grain size B) melting temperature C) mineralogy D) viscosity

100. What geologist is credited with figuring out the origin of granite? A) N.L. Bowen B) Charles Darwin C) James Hutton D) Alfred Wegener

101. Which of the following igneous rocks crystallizes at the Earth's surface? A) basalt B) gabbro C) granite D) peridotite

102. What type of volcanic rock contains a large number of vesicles (bubbles) that form when gases escape from the solidifying melt? A) granite B) obsidian C) porphyry D) pumice

103. Which of the following igneous rocks does not consist of volcanic glass? A) ash B) gabbro C) obsidian D) pumice

104. What is the approximate silica content of granite? A) 30% B) 50% C) 70% D) 90%

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105. Which of the following minerals is common in both felsic and mafic igneous rocks? A) olivine B) plagioclase feldspar C) pyroxene D) quartz

106. Which of the following igneous rocks has the lowest silica content? A) felsic B) intermediate C) mafic D) ultramafic

107. Which of the following best describes a rhyolite? A) fine-grained igneous rock rich in silica B) fine-grained igneous rock poor in silica C) coarse-grained igneous rock rich in silica D) coarse-grained igneous rock poor in silica

108. Which of the following minerals is rarely found in felsic igneous rocks? A) olivine B) orthoclase feldspar C) plagioclase feldspar D) quartz

109. Andesite is an example of a(n) __________ igneous rock. A) felsic B) intermediate C) mafic D) ultramafic

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110. Which of the following best describes the igneous rock depicted in the diagram below?

A) B) C) D)

basalt diorite granite rhyolite

111. Which of the following igneous rocks has the same chemical composition as basalt? A) andesite B) diorite C) gabbro D) rhyolite

112. Which of the following pairs of intrusive and extrusive rocks have the same chemical composition? A) diorite and rhyolite B) gabbro and rhyolite C) gabbro and basalt D) granite and andesite

113. Which igneous rock is the most abundant igneous rock of the crust and underlies virtually all of the floors of the ocean? A) andesite B) basalt C) granite D) peridotite

114. Which of the following properties increases in the direction of the arrows in the diagram below?

Felsic A) B) C) D)

Intermediate

melting temperature potassium content silica content viscosity

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Mafic

115. Which of the following statements is true? A) Gabbro has a higher melting temperature than granite. B) Gabbro has a higher potassium content than granite. C) Gabbro has a higher silica content than granite. D) Gabbro has a higher viscosity than granite.

116. Which of the following types of igneous rocks crystallizes deep within the Earth's crust? A) andesite B) basalt C) gabbro D) rhyolite

117. Which of the following lists is in the correct order of increasing silica content? A) diorite → granite → gabbro B) gabbro → diorite → granite C) gabbro → granite → diorite D) granite → diorite → gabbro

118. What composition is the Palisades sill located near New York? A) felsic B) intermediate C) mafic D) ultramafic

119. At approximately what temperature do olivine and calcium-rich plagioclase feldspar crystallize from a magma? A) 300°C B) 600°C C) 1200°C D) 2000°C

120. Which of the following minerals crystallizes from a magma at the lowest temperature? A) calcium-rich feldspar B) olivine C) pyroxene D) quartz

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121. Large igneous bodies that form at depth in the Earth's crust are called ______. A) dikes B) plutons C) sills D) veins

122. Which of the following best describes the gray igneous rock depicted in the crosssection below?

A) B) C) D)

dike lava flow pluton sill

123. How can a sill be distinguished from a lava flow? A) A sill is generally finer-grained than a lava flow. B) Rocks above and below a sill will show evidence of heating, but only the rocks below a lava flow will show evidence of heating. C) Sills generally have vesicles; lava flows generally do not have vesicles. D) Sills generally overlie soils; lava flows do not generally overlie soils.

124. Magma is by definition: A) molten rock ejected into the air B) solid rock ejected into the air C) molten rock below the surface D) molten rock on the surface

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