Oceanography Exam 1: Chapters 1-4

50. At which of these locations is the Earth's crust thickest? a. Beneath Denver, high in the Rocky Mountains. b. Beneath Los Angeles, at the Pacific coast. c. Beneath Washington, D.C., on the trailing edge of the continent. d. Beneath the ocean floor 2,000 kilometers south of Honolulu. e. The crust is about the same thickness all over the Earth.

a. Beneath Denver, high in the Rocky Mountains.

54. Which type of crust comprises the bulk of the continents? a. Granitic rock (sial) b. Basaltic rock (sima)

a. Granitic rock (sial)

26. If we had to make a selection, which of these people would probably be given the title of "first ocean scientist?" a. Matthew Maury b. Captain James Cook c. Christopher Columbus d. Wyville Thompson (of the Challenger expedition). e. Ben Franklin

a. Matthew Maury

64. New crust is being generated: a. In the deep trenches. b. In submarine canyons. c. In the rift valleys of the mid-ocean ridges. d. At the centers of large continents. e. In all of these places.

c. In the rift valleys of the mid-ocean ridges.

93. An analysis of the sequential breaking of transatlantic telephone and telegraph cables led to a better understanding of a. the distribution of submarine trenches. b. the composition of sediments. c. turbidity currents d. hydrothermal vent communities. e. the size of the ocean.

c. turbidity currents

12. About what percentage of the Earth's surface is covered by water? a. 71% b. 90% c. 66% d. 75% e. 82%

a. 71%

98. Underlying the unconsolidated pelagic sediments of the seafloor are: a. Basalt pillows and other mafic basement rocks. b. Granite boulders. c. Glacial deposits left from the Ice Age. d. Ancient remnants of sunken continents.

a. Basalt pillows and other mafic basement rocks.

22. The first life forms on Earth arose: a. More than 3.5 billion years ago. b. At the same time as the formation of the Earth. c. Relatively recently -- about 250,000,000 years ago. d. About 10,000 years ago.

a. More than 3.5 billion years ago.

1. Of all the planets in the solar system, the Earth is the only planet to have large quantities of liquid water on its surface. a. True b. False

a. True

9. The main contributions of Chinese voyaging to marine science was the compass, battened sails, and watertight hull compartmentalization. a. True b. False

a. True

72. Ophiolites are: a. fragments of dense oceanic crust contained in terranes. b. bits of fossilized worms useful in dating marine sediments. c. young, serpent-shaped rocks formed at subduction zones. d. fragments of meteorites lying on the seabed. e. formations comprising more than half the solid ocean floor.

a. fragments of dense oceanic crust contained in terranes.

97. Which of the following metals is also found in manganese nodules: a. iron. b. uranium. c. lithium. d. silver. e. gold.

a. iron.

83. The origin of submarine canyons is not well understood, but most likely a. is erosional, started by streams during periods of sea level lowering. b. is tectonic, and represents down-folds of rock within the continental shelf. c. is organic, resulting from the activities of burrowing organisms. d. is glacial, the work of glaciers depositing rock debris on the shelf.

a. is erosional, started by streams during periods of sea level lowering.

55. Which of these is most abundant on or in the Earth? a. mantle material. b. granite rock c. liquid water d. basalt e. inner core

a. mantle material.

14. In the scientific method, scientific theories a. must be tested and verified by observations. b. must be verified by the leading authorities in the field. c. must be consistent with previous, universally accepted scientific concepts. d. must be consistent with the fact that the ocean is of great age. e. are accepted as absolute fact until proven otherwise.

a. must be tested and verified by observations.

16. The condensation theory proposes that our solar system formed from a: a. single accreting disc (flat cloud) of debris, dust and gas. b. set of individual, separate discs. c. larger star that split into sections. d. larger planet that split into fragments.

a. single accreting disc (flat cloud) of debris, dust and gas.

82. The great heaps of unconsolidated sediment at the base of the continental slope are known as: a. the continental rise. b. the abyssal hills. c. the abyssal plains. d. the mid-ocean mountains. e. the mid-ocean ridge.

a. the continental rise.

10. Earth is about a. 6,000 years old. b. 4.6 billion years old. c. 4.6 million years old. d. 40 billion years old. e. 400,000 years old.

b. 4.6 billion years old.

51. Which type of crust is made largely of silicon, magnesium, and iron? a. Granitic rock (sial) b. Basaltic rock (sima)

b. Basaltic rock (sima)

52. Which type of crust makes up the actual deep seafloor (beneath the sediments)? a. Granitic rock (sial) b. Basaltic rock (sima)

b. Basaltic rock (sima)

53. Which type of crust is the denser of the two? a. Granitic rock (sial) b. Basaltic rock (sima)

b. Basaltic rock (sima)

56. Why is the inner core a solid? a. Because it is so hot. b. Because it is under tremendous pressure. c. Because of a chemical reaction with the outer core. d. Because it is composed mainly of iron and nickel. e. It is not a solid.

b. Because it is under tremendous pressure.

46. Why is the inside of the Earth still hot? a. Because the outer layers have prevented the escape of heat trapped during the planet's initial formation, and no new heat has been formed. b. Because the decay of large radioactive elements is creating heat in the Earth's inner layers. c. Because a nuclear process like that found in stars is at work in Earth's interior. d. Because huge quantities of oil and natural gas occasionally burn deep within the Earth. e. Actually, the inside of the earth is quite cool; it's only the outer layers that are still hot, and this heat is caused by the sun.

b. Because the decay of large radioactive elements is creating heat in the Earth's inner layers.

58. A "mystery" in our understanding of plate tectonics has been, until recently, the nature of the power source capable of moving the plates and the continents embedded within them. Recent evidence indicates the power source to be: a. The readjustment of the surface to continual shrinking of the whole Earth. b. Convection currents within the Earth's mantle is moving the plates. c. The action of ocean currents is dragging along the seafloor, causing the seafloor and the continents to move. d. the continual vibration from earthquakes and volcanoes slowly moves the continents equatorward under the influence of centrifugal force. e. The whole business is quite new, actually, having been triggered by H-bomb tests in the Pacific in the mid-1950s.

b. Convection currents within the Earth's mantle is moving the plates.

2. The average height of the continents above sea level is greater than the average depth of the ocean. a. True b. False

b. False

3. The Earth has always had an atmosphere with the composition as it has today. a. True b. False

b. False

4. The Earth has always had an atmosphere about as dense as it has today. a. True b. False

b. False

5. Humanity did not spread to virtually all the inhabitable areas of the Earth until after the European voyages of discovery in the late 1400s and early 1500s. a. True b. False

b. False

6. The first awareness of the spherical shape of the Earth developed in Europe around 1450 with the work of Henry the Navigator. a. True b. False

b. False

7. Radiometric dating works by measuring the rate of decrease in the radioactivity of naturally radioactive materials. a. True b. False

b. False

8. Most of the future deep-ocean research being planned by oceanographers involves sending human pilots and observers to the greatest ocean depths in vehicles like Alvin, Trieste, and Shinkai-6500. a. True b. False

b. False

21. Our position within the galaxy is: a. At the center. b. In a spiral arm, surrounded by dust and gas. c. Above the polar axis. d. At a vast distance from the galaxy itself. e. We're not in a galaxy.

b. In a spiral arm, surrounded by dust and gas.

48. When a substance is resting in buoyant equilibrium, moving neither up nor down: a. It weighs less than the water surrounding it. b. It displaces a volume of water equal in weight to its own weight. c. It displaces a volume of water which weighs slightly more than its own weight. d. It displaces a volume of water which weighs slightly less than its own weight. e. It weighs more than the water surrounding it.

b. It displaces a volume of water equal in weight to its own weight.

69. Analysis of plate motion suggests: a. California is going to sink into the Pacific any day now. b. Part of California west of the San Andreas Fault is moving northward. c. Part of California and Baja California are moving southward into the Peru Trench. d. Southern California is being subducted into the Malibu Trench.

b. Part of California west of the San Andreas Fault is moving northward

23. Which hemisphere of the Earth contains the greater proportion of ocean surface? a. Northern. b. Southern. c. Both about equal.

b. Southern.

28. If selections were to be made, which of these voyages would qualify as the first 100% pure scientific oceanographic expedition? a. Columbus' 1496 trip. b. The Challenger expedition. c. Benjamin Franklin's first voyage across the Atlantic to take up his post as American Ambassador to France. d. Captain Cook's voyage to Tahiti in the ship Endeavour. e. The Chinese voyages undertaken during the Ming Dynasty.

b. The Challenger expedition.

71. The rigid outermost layer of the Earth is called: a. The asthenosphere. b. The lithosphere. c. The mantle. d. The Mohorovicic discontinuity. e. The outer core.

b. The lithosphere.

78. Which of the following statements accurately describes passive continental margins? a. They are regions of bordered by oceanic trenches. b. They are characteristic of the margins of the Atlantic Basin. c. They are areas of frequent earthquakes and volcanoes, where crustal plates are converging or are in collision. d. They are areas where crustal plates are actively moving apart. e. They are usually different in topography from the adjoining coast.

b. They are characteristic of the margins of the Atlantic Basin.

67. Which of the following statements does not correctly describe subduction zones? a. They are belts of deep-focus earthquakes. b. They are sites where crustal plates are diverging or pulling apart. c. They are marked by the presence of deep-sea trenches. d. They are zones where old seafloor descends into the crust and mantle.

b. They are sites where crustal plates are diverging or pulling apart.

73. Although 99% of the ocean floor is unexplored, have people reached essentially the deepest spot in the ocean and returned safely to the surface? a. Yes, and just recently (in 1997). b. Yes, but it was some while ago, in the 1950s. c. Yes, and it was a French expedition led by Jacques-Yves Cousteau's son Jean-Michel. d. No, not yet, though a trip is now being planned. e. No, and such a trip is not considered possible.

b. Yes, but it was some while ago, in the 1950s.

91. Hydrothermal springs seem to be located near: a. passive continental margins. b. active areas of seafloor spreading. c. the edges of the deep sea trenches. d. the margins of the Hawaiian chain. e. on the abyssal plains.

b. active areas of seafloor spreading.

35. Matthew Maury is known primarily for: a. his co-discovery of gold at Sutter's Mill in California, triggering the gold rush and subsequent large-scale use of shipborne passenger transportation. b. being the first person to sense the worldwide pattern of surface winds and currents, and to base sailing directions on this knowledge. c. interpreting the scientific information coded in Captain Cooks private notebooks. d. founding the United States Naval Academy at Annapolis, Maryland. e. co-writing, with Alfred Thayer Mahan, The Influence of Sea Power Upon History (1890).

b. being the first person to sense the worldwide pattern of surface winds and currents, and to base sailing directions on this knowledge.

57. Would you agree that the position of the true geological edge of a continent is almost always the same as the position of its shoreline? a. agree (yes) b. disagree (no)

b. disagree (no)

15. Life on Earth most probably evolved a. on land. b. in the ocean. c. in space.

b. in the ocean.

40. What is the name of the outermost solid layer of the Earth? a. hydrosphere b. lithosphere c. asthenosphere d. outer core e. none of the above

b. lithosphere

61. The youngest seafloor rocks are found: a. nearest the continental slopes. b. near the rift valleys of the mid-ocean ridges. c. beneath the deep sea trenches. d. evenly distributed over the ocean basins. e. underlying the continental shelves.

b. near the rift valleys of the mid-ocean ridges.

81. The origin of deltas is related to: a. glacial deposition and the formation of moraines. b. river deposition of sediments eroded from continents. c. glacial erosion and the formation of troughs and fjords. d. volcanic activity in coastal regions. e. biological activity of corals, cyanobacteria, and small shelled organisms.

b. river deposition of sediments eroded from continents.

94. Which is greater, the average height of the continents or the average depth of the ocean? a. the average height of the continents. b. the average depth of the ocean.

b. the average depth of the ocean.

79. The transition between the shelf and the deep seafloor is a. the littoral zone. b. the continental slope and rise. c. the abyssal plain. d. the mid-ocean ridge. e. the submarine canyon.

b. the continental slope and rise.

95. Which is greater, the height of the world's tallest mountain or the depth of the world's greatest trench? a. the height of the mountain (Mt. Everest). b. the depth of the trench (Challenger Deep).

b. the depth of the trench (Challenger Deep).

33. Who discovered North America? a. Columbus b. the native Americans c. The Chinese Admiral Zheng d. Bjarni Herjulfsson e. Eratosthenes of Cyrene

b. the native Americans

87. The characteristics of deep trenches indicate a. they are erosional features similar to the Grand Canyon in Arizona. b. they are deep, elongated creases in the seafloor where oceanic crust is being subducted. c. they are glacial troughs dating back to the Ice Age. d. they are erosional canyons cut by turbidity currents.

b. they are deep, elongated creases in the seafloor where oceanic crust is being subducted.

66. Oceanographers believe the breakup of Pangaea occurred about: a. 1 million years ago. b. 10 - 25 million years ago. c. 190 to 225 million years ago. d. 750 million years ago. e. 2 billion years ago.

c. 190 to 225 million years ago.

17. The ocean originated from: a. Volcanic gases. b. Radioactive heating of the Earth's interior, and the heating of the surface by meteorites striking and melting the outer icy layers of the Earth. c. Capture by the Earth's gravity of water from space via comets. d. a and c only.

c. Capture by the Earth's gravity of water from space via comets.

45. As you know, Earth is layered inside. The layers have different sizes and densities. How do geologists knows this? a. From drilling and digging down into the various layers. b. From observing the characteristics of lava and gas issuing from volcanic vents. c. From observing the transit times through the Earth of waves generated by large earthquakes. d. From comparisons with drill cores taken by robot spacecraft on Mars and Venus. e. None of these.

c. From observing the transit times through the Earth of waves generated by large earthquakes.

11. Other than the hydrogen atoms that are found in water, where were the atoms thatmaker up seawater formed? I don't mean where were they stored through the Earth's early "childhood," I mean where were the atoms heavier than hydrogen actually constructed? a. In the Earth's upper atmosphere. b. Deep within the Earth while it was forming. c. In a star or stars before there even was an Earth. d. At the instant of the "big bang". e. At the junction between the atmosphere and space.

c. In a star or stars before there even was an Earth. Hydrogen and Helium was due to the Big Bang. Medium Elements-star fusion Heavy Elements- Star(super) Novas

24. What will happen to the Earth? a. Any day now, it will disappear as the sun becomes a supernova. b. In about 5 billion years, the sun will become a supernova, and our descendants (if any) will fry. c. In about 5 billion years, the sun will gradually begin to swell, and our descendants (if any) will be roasted. d. In about 5 billion years the sun will cool and our descendants (if any) will all freeze to death.

c. In about 5 billion years, the sun will gradually begin to swell, and our descendants (if any) will be roasted.

76. Submarine canyons occur: a. At the part of an ocean basin nearest the poles. b. At the part of an ocean basin nearest the equator. c. Near the edges of ocean basins associated with continental shelves and slopes. d. At the center of an ocean basin, at the edges of the mid-ocean ridge. e. On the edges of trenches.

c. Near the edges of ocean basins associated with continental shelves and slopes.

100. Carbonate sediments are rare in deep sea sediments because: a. The organisms providing shells do not live in the deep sea. b. The abundance of muds and clays cover the carbonate shells. c. The carbonate shells dissolve in deep water. d. The organisms do not live beyond the edge of the continental shelf.

c. The carbonate shells dissolve in deep water.

29. The future of oceanographic research appears to lie: a. With single, isolated individuals working alone. b. With epic voyages. c. With the great private, institutional, and national oceanographic institutions. d. With the navies of the world.

c. With the great private, institutional, and national oceanographic institutions.

88. Mid-ocean ridge mountain systems, like that running down the middle of the Atlantic, a. are similar in origin to the Alps, the Rockies, and the Appalachians. b. are composed of folded and faulted marine sedimentary rocks. c. are constructed of normal fault-bounded blocks of volcanic basalt. d. are similar in size and composition to most continental mountains.

c. are constructed of normal fault-bounded blocks of volcanic basalt.

18. Evidence suggests the universe began about 15 billion years ago in a a. slow accretion of atoms. b. very large galaxy. c. cataclysmic explosion of energy and matter. d. protostar. e. supernova.

c. cataclysmic explosion of energy and matter.

68. The mid-ocean ridges are recognized as: a. subduction zones. b. transform or lateral plate boundaries. c. divergent plate boundaries. d. convergent plate boundaries.

c. divergent plate boundaries.

27. John Harrison's invention of the chronometer was important because: a. it enabled sailors to calculate local time. b. it allowed the calculation of latitude after weeks at sea. c. it allowed the calculation of longitude after weeks at sea. d. it was used to calibrate navigational tools. e. the devices were very valuable and were considered works of art.

c. it allowed the calculation of longitude after weeks at sea.

85. Active continental margins are located a. along the east coast of the United States. b. along the east coast of South America. c. on the west coasts of both North and South America. d. all around Africa.

c. on the west coasts of both North and South America.

42. Here are five lists of elements. Which list represents the main components of the Earth's crust? a. oxygen, uranium, thorium b. oxygen, silicon, uranium c. oxygen, silicon, aluminum d. iron, aluminum, carbon e. iron, hydrogen, oxygen

c. oxygen, silicon, aluminum

25. The ocean continues to grow slowly in volume. Most of the 0.1 cubic kilometer (0.025 cubic mile) of new water being added annually to the ocean comes from: a. outer space. b. conversion of seafloor rocks into water by bacteria. c. within the Earth as volcanic steam. d. from the combustion of oil and natural gas.

c. within the Earth as volcanic steam.

75. The average width of the continental shelves is about ____ kilometers (____ miles). a. 16 (10) b. 35 (22) c. 67 (42) d. 100 (160) e. 800 (1,280)

d. 100 (160)

41. About how many kilometers (miles) is it from the Earth's center to the outer edge of the outer core? a. 12,523 kilometers (7,827 miles) b. 3,486 kilometers (2,167 miles) c. 1,264 kilometers (790 miles) d. 2,880 kilometers (1,800 miles) e. 35 - 72 kilometers (22 - 45 miles)

d. 2,880 kilometers (1,800 miles)

13. About what percentage of the water on or near the Earth's surface is contained in the ocean? a. 55% b. 75% c. 85% d. 97% e. 100%

d. 97%

70. Roughly how fast do most lithospheric plates move? a. About 3 kilometers per hour. b. About 3 kilometers per thousand years. c. About 3 centimeters per hour. d. About 3 centimeters per year. e. About 3 centimeters per million years.

d. About 3 centimeters per year.

19. Until recently, many scientists were tentative in their acceptance of the theory of the chemical evolution of life on Earth. What has changed their minds? a. The discovery of organic molecules in space. b. The discovery of organic molecules at geothermal vents on the deep seafloor. c. Experiments in which organic molecules were synthesized in chambers replicating a hypothetical early Earth environment. d. All of the above.

d. All of the above.

20. Life could almost certainly not originate anew on this planet today. This is because: a. Green plants have filled the atmosphere with oxygen, a compound that can disrupt unprotected large molecules. b. Ozone now blocks much ultraviolet radiation from reaching the Earth's surface, depriving molecules one of the sources of energy needed for polymerization. c. Micro-organisms present on the Earth and in the ocean would gladly scavenge any large organic molecules that might form. d. All of the above.

d. All of the above.

92. In general, continental shelves tend to be wider in the a. Pacific ocean, because its margins tend to be active. b. Atlantic ocean, because its margins tend to be active. c. Pacific ocean, because its margins tend to be passive d. Atlantic ocean, because its margins tend to be passive.

d. Atlantic ocean, because its margins tend to be passive.

59. If two oceanic plates collide at a relatively fast speed, and one is much older and cooler (therefore denser) than the other, what will probably happen? a. A trench will form. b. Continental mountains will form. c. Large earthquakes will occur. d. a and c. e. b and c.

d. a and c.

34. In the original Greek conception, oceanus was: a. Earth. b. the Mediterranean Sea. c. an imaginary concept. d. a great flowing river. e. none of the above.

d. a great flowing river.

38. At the present time, oceanographic research is primarily the province of: a. private individuals, privately funded. b. private individuals, funded through national or local grants. c. private corporations, privately funded. d. academic institutions or governmental agencies, publicly funded. e. private corporations, publicly funded.

d. academic institutions or governmental agencies, publicly funded.

89. The islands bordering the deep-sea trenches a. result from a series of quiet, continuous basaltic eruptions. b. are accumulations of sediments on the margins of the trenches. c. are formed from the activities of coral and other organisms. d. are explosive volcanoes that emit andesite lavas.

d. are explosive volcanoes that emit andesite lavas.

36. The first scientific expedition to use an echo sounder occurred during the: a. late 1700's b. early 1800's c. late 1800's d. early 1900's e. late 1900's

d. early 1900's

86. The landscape of the deep seafloor would best be described as a. a featureless plain. b. a smooth descent with the deepest portions farthest from land. c. similar in rock type, sediment thickness, and erosional processes to those found on the land. d. having ridges, trenches, seamounts, and other features different from those found on land.

d. having ridges, trenches, seamounts, and other features different from those found on land.

43. The core of the Earth is composed primarily of: a. uranium b. nickel c. metallic hydrogen d. iron e. lead

d. iron

77. The continental shelf a. is very narrow on the East Coast of the United States. b. is a steeply dipping zone dropping off to the deep seafloor. c. is a featureless plain unlike the neighboring continent. d. is a gently sloping platform with a variable landscape, including submarine canyons. e. all of the above.

d. is a gently sloping platform with a variable landscape, including submarine canyons.

96. The oozes on the seafloor mostly consist of: a. boulders and cobbles from glaciers oozing off the land. b. bones and teeth of bottom-dwelling fishes. c. fine muds washed down the continental slope to the seafloor. d. microscopic hard parts of single-celled surface living organisms. e. treated sewage from urban areas.

d. microscopic hard parts of single-celled surface living organisms.

90. The deepest parts of the Pacific Basin are located: a. in the center, surrounding the island of Hawaii. b. in the eastern part of the basin, off North America. c. in the rift valley of the East Pacific Rise. d. near the margins of South America, Japan, and the Mariana's Islands.

d. near the margins of South America, Japan, and the Mariana's Islands.

84. The trailing edge of a moving continental mass is most likely to exhibit features associated with a. frequent earthquake activity. b. active continental margins. c. widespread volcanism. d. passive continental margins.

d. passive continental margins.

62. The magnetic striping of the seafloor is considered evidence of seafloor spreading and a. subduction down the rift valleys. b. spreading centers in the trenches. c. changes in the Earth's axis of rotation. d. periodic reversals in the polarity of the Earth's magnetic field. e. periodic collapses of the Earth's gravitational field.

d. periodic reversals in the polarity of the Earth's magnetic field.

37. Glomar Challenger is known mainly for: a. being the first modern scientific survey ship to circumnavigate the globe. b. being the first nuclear powered scientific research vessel. c. being owned and operated simultaneously by four governmental agencies. d. taking the first complete cores of deep-sea sediments. e. sinking in 1983 under mysterious circumstances.

d. taking the first complete cores of deep-sea sediments.

99. Large volumes of bottom sediments may be transported long distances by a. storm waves. b. icebergs. c. tidal action. d. turbidity currents.

d. turbidity currents.

63. The Earth's oldest rocks are found: a. In the deepest part of the flat ocean bottom. b. At the mid-ocean ridges. c. On volcanic islands like Hawaii. d. In the trenches. e. At the cores of the continents.

e. At the cores of the continents.

65. The force driving the crustal plates is believed to be: a. Magnetism. b. Gravity. c. The pull of the sun and the moon. d. Deep water currents pulling on the ocean basins. e. Convection cells in the upper mantle and the tug of the descending plates.

e. Convection cells in the upper mantle and the tug of the descending plates.

32. Captain James Cook accomplished all of these tasks except: a. First European to contact the Hawaiian Islands. b. First to circumnavigate the world near Antarctica. c. Made three major voyages of discovery. d. Mapped the coasts of Australia and New Zealand. e. First European to explore the South Pacific.

e. First European to explore the South Pacific.

74. A turbidity current is: a. A fast surface current of water that runs parallel to beaches and that causes a rapid decrease in water clarity. b. The cause of mid-ocean maelstroms (whirlpools). c. A phenomenon associated with violent atmospheric storms at sea. d. Something that always occurs at river mouths in shallow water, but does not extend into water more than 50 meters (165 feet) deep. e. None of the above.

e. None of the above.

30. Long-range ocean travel was first under taken by the _________, later by the _________, and last by the _________. (Select the proper chronological order.) a. Europeans/Polynesians/Scandinavians (=Vikings) b. Europeans/Scandinavians/Polynesians c. Polynesians/Europeans/Scandinavians d. Scandinavians/Polynesians/Europeans e. Polynesians/Scandinavians/Europeans

e. Polynesians/Scandinavians/Europeans

47. What do these things have in common: Paleomagnetism, seafloor spreading, Pangaea, Wadati-Benioff zones, transform faults, fracture zones, seamount chains, Pacific hotspots. a. They are all used to study earthquakes. b. They were discovered in the Challenger expedition. c. They are used to investigate the potential for undersea mining and mineral resource exploitation. d. They are used to predict earthquake activity and warn people of imminent danger. e. They are involved with the theory of plate tectonics.

e. They are involved with the theory of plate tectonics.

39. TOPEX/Poseidon is: a. the name of a Greek ocean god. b. an agency within NOAA. c. the code name for the U. S. Navy's ocean research program. d. a federal program to fund oceanographic research. e. a joint French - U.S. satellite (and associated consortia) devoted to oceanic research.

e. a joint French - U.S. satellite (and associated consortia) devoted to oceanic research.

49. An example of an object in buoyant (or isostatic) equilibrium would be: a. An ice cube floating in a glass of water. b. A continent "floating" on heavier material below. c. A table standing on a concrete floor. d. A person standing on a gravel driveway. e. a. and b. above.

e. a. and b. above.

31. Polynesian navigators depended on _____________ for accurate navigation. a. luck. b. stars, clouds, and the flight direction of birds. c. the appearance and taste of seawater. d. wave direction and shape. e. all of these things, and more.

e. all of these things, and more.

60. Land-based evidence for plate tectonics can be seen in: a. the distribution of Glossopteris flora and fauna. b. evidence of ancient glaciations. c. the alignment of mountain ranges. d. the correlation of rocks in now widely separated continents. e. all of these.

e. all of these.

80. Submarine canyons are a. found worldwide, on all kinds of shelves. b. steep-walled and narrow. c. cut into firm rock. d. cut into the shelf and may extend almost to the shore. e. all of these.

e. all of these.

44. One cubic meter of which of is the most dense? a. seawater b. granite rock c. basaltic rock d. seabed sediment e. mantle

e. mantle