Ch07 Plate Tectonics Underlies All Earth History Test.docx

The Earth Through Time Chapter 7—Plate Tectonics Underlies All Earth History Multiple Choice Questions Select the best answer. 1. Which seismic wave propagates a pull-push motion? a. T - wave b. S - wave c. Love wave d. P - wave e. Rayleigh wave 2. What wave travels the fastest? a. T - wave b. S - wave c. Love wave d. P - wave e. Rayleigh wave 3. Which layer of the Earth inhibits the propagation of the S-wave? a. Inner core b. Outer core c. Mantle d. Sub mantle e. Crust 4. What is it called when an abrupt change in seismic wave velocity take place at the base of the crust? a. Gutenberg discontinuity b. Newton c. Low velocity zone d. Reflection e. Moho discontinuity 5. What evidence is sighted for the outer core being liquid? a. Disappearance of the S-wave b. Marked slowdown in the P-wave c. Both A and B d. Neither A or B e. Changes in the Z-wave 6. Which of the following is evidence that the Earth’s core is metallic? a. lab experiments with iron-nickel mixtures b. Magnetic field c. Earth’s density d. Meteorites e. All the above 7. Which rock type is inferred to make up the mantle? a. peridotite b. iron c. magnesium d. silicon e. oxygen 8. The _____________ serves as a slip plain for the lithosphere. a. upper mantle b. asthenosphere c. lower mantle d. outer core e. inner core 9. The ocean’s crust is primarily composed of ______________. a. mafic igneous rocks b. felsic igneous rocks c. metamorphic rocks d. intermediate igneous rocks e. granite 10. Continental crust has an average density of ____. a. 10 g/cm3 b. 5.5 kg/cm3 c. 2.7 g/cm3 d. 1.7 mg/cm3 e. 2.7 µg/m3 11. On what layer of the Earth do the tectonic plates float? a. Mantle b. Crust c. Inner core d. Asthenosphere e. Outer core 12. If you could take one cubic foot of the ocean crust and one cubic foot of continental crust and float each in a tube of molasses, which would float higher? a. Neither, they would float at the same level b. Ocean crust c. Continental crust d. Neither, both would sink e. None of the above 13. Wegener postulated the existence of a supercontinent named _______________. a. the supercontinent b. Laurasia c. Ozeane d. Pangea e. Gondwanaland. 14. Which of the following is paleoclimatological evidence for continental drift? a. Magnetic reversals b. Lack of annual tree rings in fossilized trees c. Orientation of mountain ranges d. The fit of the continental margins e. Apparent polar wandering 15. In what modern region do evaporites tend to form? a. 60° North and South of the Equator b. 30° North and South of the Equator c. At the equator d. Near the Prime Meridian e. Antarctic 16. What plant fossil did Wegener use to line up the continents? a. Lystrosaurus b. Glossopteris c. Mesosaurus d. Cynognathus e. Guyots 17. The magnetic field of the Earth is recorded by the mineral _________________. a. magnetite b. quartz c. feldspar d. mica e. olivine 18. The idea of apparent polar wandering is that the magnetic poles _____________. a. move locations b. are stationary c. are at different locations for the stationary continents d. at the equator e. None of the above 19. The plates in plate tectonics are composed of _____________________. a. mantle b. crust and part of the mantle c. inner core d. asthenosphere e. outer core 20. What is the predominate force associated with a divergent plate boundary? a. Compression b. Fictional c. Shear d. Tensional e. Stressful 21. Hess recognized that guyots were _____________________. a. volcanoes formed at midoceanic ridges b. mounds of sediments c. narrow bays d. submarine valleys e. trenches 22. What is the name of the faults that connects offset ridges? a. double faults b. transform faults c. lateral faults d. normal faults e. thrust faults 23. Transform boundaries unlike divergent or convergent boundaries do not generate _________________? a. offset b. earthquakes c. seismic waves d. border between plates e. intense igneous activity 24. What is responsible for partially melting the mantel in subduction zone regions? a. the addition of nitrogen b. the release of nitrogen c. the addition of water d. the release of water e. the addition of a flammable liquid 25. Which type of convergent margin does not have subduction? a. ocean - ocean b. continental - continental c. transform plate boundaries d. divergent plate boundaries e. continental - ocean 26. What is the name of a sequence of rocks that represent ocean crust? a. granite b. tonolite c. ophiolite d. blueschists e. red beds . 27. What is the name of a metamorphic rock produced in a subduction zone? a. granite b. tonolite c. ophiolite d. blueschists e. red beds 28. What is it called when a continent splits apart forming an ocean than later re- converges? a. Hess Event b. Gutenberg Formation c. Wilson Cycle d. Mohorovi?i? Cycle e. Levin Event 29. Plates move in part by mantle rocks slowly circulating in large ___________. a. convection cells b. subduction cells c. conduction cells d. figure eights e. volcanoes 30. Which of the following models for driving plate motion operate at the subduction zones? a. Slab push b. Ridge pull c. Plate pull d. Plate push e. Slab pull 31. Which of the following is responsible for the magnetic strips in the sea floor? a. Slab push b. Ridge pull c. Magnetic reversals d. Pangea e. Slab pull 32. The age of the sea floor basalts was measured by ____________________. a. radiometric dating of seafloor basalts b. radiometric dating of land vertebrates c. Principle of superpostion d. Matching the magnetic reversed pattern with those of continental basalt of known age e. None of the above 33. Plates with large continents on them tend to travel ________ than plates without large continents a. closer to the poles b. more to the west c. more to the east d. faster e. slower 34. Where should the youngest and thinnest seafloor sediments be found? a. The center of the Earth b. The surface of the ocean c. Continental crust d. The midoceanic ridge e. The nearest hot spot 35. What is the name of the line of earthquakes that descend into the mantle at subduction zones? a. Hess - Gutenberg seismic zone b. Wadati - Benioff seismic zone c. Wilson - Levin seismic zone d. Mohorovi?i? Cycle e. Gravity anomaly 36. The Hawaii Islands have been formed by a stationary source of magma call an ____________. a. lateral faults b. subduction zone c. hot spots d. midoceanic ridge e. continental rifting 37. Much of Alaska was built by microcontinents slamming into North America. The newly added land masses are called _______________. a. hot spot b. exotic terrane c. guyot d. Wadati-Benioff zone e. ophiolite 38. In normal faults the hanging wall moves ______________. a. up b. down c. diagonally d. to the right e. to the left 39. Which of the following fault types shorten the crust? a. reverse b. thrust c. strike-slip d. normal e. Both a. and b. 40. You are standing in the center of a fold and start walking perpendicular to the axis of the fold. If the rocks become older, what type of fold is it? a. basin b. monocline c. syncline d. dome e. anticline Answers to Questions 1. d 11. d 21. a 31. c 2. d 12. c 22. b 32. d 3. b 13. d 23. e 33. e 4. e 14. b 24. d 34. d 5. c 15. b 25. b 35. b 6. e 16. b 26. c 36. c 7. a 17. a 27. d 37. b 8. b 18. c 28. c 38. b 9. a 19. b 29. a 39. e 10. c 20. d 30. e 40. e TEST 2 Multiple Choice Questions 1. The location, thickness, and some properties of the Earth's internal zones may be determined using: seismic waves. crustal structures. paleomagnetism. thermal convection cells. hot spots. Ans: a Feedback: See page 170 2. The fastest of the three types of seismic waves is called: primary waves. secondary waves. surface waves. tsunamis. magnetic waves. Ans: a Feedback: See page 170 3. Plate tectonic theory explains or has helped to explain: the global pattern of earthquakes and volcanoes. the locations of mountain systems. ancient climatic patterns and ocean circulation. the geographic distribution, evolution, and extinction of life. all of the above. Ans: e Feedback: See pages 179-182 4. Secondary earthquake waves generated on one side of the Earth failing to appear on the other side of the Earth is the principle observational evidence for what layer within the Earth? crust mantle liquid outer core solid inner core asthenosphere Ans: c Feedback: See page 172 5. Plate tectonic movement of the lithospheric plates may be based in part on large thermal convection cells in the Earth’s: crust. asthenosphere. liquid outer core. solid inner core. lithosphere. Ans: b Feedback: See page 194 6 .The igneous rocks that make up much of the oceanic crust is: granite and andesite. shale and siltstone. limestone and chert. basalt and gabbro. e) peridotite and gabbro. Ans: d Feedback: See page 175 7. The lower density of the continental crust results from its composition, which approximates this rock type: schist. andesite. limestone. peridotite. basalt. Ans: b Feedback: See page 176 8. Regions of the Earth’s crust with folded rocks and this type of fault are likely to have been compressed at some time in the geologic past: thrust faults. left-lateral strike-slip faults. right-lateral strike-slip faults. oblique normal faults. normal faults. Ans: a Feedback: See pages 189 and 193 9. What type of fold consists of uparched rocks in which the oldest rocks are in the center and the youngest rocks are on the flanks? anticline syncline basin monocline archways Ans: a Feedback: See pages 206 and 208 10. What is (or was) Pangea? a fossil found on widely separated continents a portion of the oceanic ridge system a German word for plate tectonics a supercontinent that broke up an island in the Indian Ocean Ans: d Feedback: See pages 178-179 11. Midocean ridges are what type of plate boundary? convergent divergent transform subduction convection Ans: b Feedback: See page 185 12. Where tectonic plates collide, one slab may slip and plunge below the other, thus producing: a folded mountain range. Earth's magnetic field. a midocean ridge. convection cells. a subduction zone. Ans: e Feedback: See page 188 13. The magnetic stripes on the seafloor: record reversals of the Earth's magnetic field. show a symmetrical pattern with respect to the midoceanic ridge. are created as lava or magma crystallizes and cools past the Curie point. relate to all of the above. relate to none of the above. Ans: d Feedback: See page 197 14. A plot of earthquake location with depth shows that deeper earthquakes occur along a narrow zone tilted at about a 45-degree angle beneath an island arc or a continent, either of which may be adjacent to an oceanic trench. This inclined seismic zone is good evidence for the presence of: a molten outer core. a subduction zone. the Mohorovic discontinuity. a continental rift zone. the Gutenberg discontinuity. Ans: b Feedback: See pages 200-201 15 .The Hawaiian islands are ancient or currently active volcanoes because they lie: on a hot spot. on a plate boundary. adjacent to a mid-oceanic ridge. on continental crust. on a deep sea trench. Ans: a Feedback: See page 202 TEST 3 Multiple-Choice Questions 1. Seismic waves where the rock segments vibrate at right angles to the travel directions of energy and cannot pass through liquids or gases. a. primary waves c. longitudinal waves b. secondary waves d. density waves 2. Which wave reaches a seismographic station first when compared with others? a. secondary c. surface b. primary d. longitudinal 3. Boundaries where seismic waves experience an abrupt change in velocity or direction are called a. discontinuities. c. anticlines. b. shadow zones. d. synclines. 4. The feature located nearly halfway to the center of the Earth, at a depth of 2900 kilometers whose location is marked by an abrupt decrease in P-wave velocities and the disappearance of S-waves is the a. Mohorovicic discontinuity. c. lower mantle. b. Gutenberg discontinuity. d. upper mantle. 5. This zone on the side of the Earth opposite the Earth focus (rupture point of an earthquake) which begins 105 degrees from the earthquake’s location. a. shadow zone c. P-wave shadow zone b. mantle zone d. L zone 6. Which of the following is an iron and magnesium rich rock? a. granite c. hornfel rhyolite b. limestone andesite d. peridotite 7. The Earth’s mantle is composed primarily of a. oxygen, silicon, iron, and magnesium. c. silicon, potassium, and sedimentary rocks. b. iron, magnesium, and calcium. d. iron and nickel. 8. The outer shell of the Earth lying above the asthenosphere and comprising the crust and upper mantle is called a. low velocity zone. d. lithosphere. b. monocline. e. surface zone. c. Laurasia. 9. Breaks in crustal rocks along which there has been a displacement of one side relative to the other are a. folds. d. domes. b. faults. e. strata. c. synclines. 10. In normal faults, the mass of rock that lies above the shear plane is called the a. fault scarp. c. thrust fault. b. foot wall. d. hanging wall. 11. A fault in which the hanging wall moves downward in relation to the footwall is called a a. lateral fault. c. reverse fault. b. normal fault. d. strike-slip fault. 12. Reverse faults in which the shear zone is inclined only a few degrees from horizontal are termed a. normal faults. c. reverse lateral faults. b. lateral faults. d. thrust faults. 13. Downwardly folded rocks that have the youngest beds in the center and the oldest rocks on the flanks are called a. anticlines. c. folds. b. synclines. d. basins. 14. The characteristic of anticlines and domes in relation to the instability of folds is a. a down-folded strata with the basin being more or less circular. b. strata that dips for an indefinite length in one direction and returns to its former horizontal attitude. c. an up-arched strata with beds dipping more or less equally away from a central point. d. a downward hanging wall relative to a foot wall. 15. Gondwanaland included which three present day continents? a. Africa, Asia, Australia c. India, South America, Southern Africa, Australia b. North America, India, Europe d. Australia, Africa, India 16. Deposits of poorly sorted clay, sand, cobbles, and boulders that are associated with glaciers are called a. suturites. c. drifts. b. tillites. d. magnalites. 17. What is a small aquatic reptile whose fossil is found in the southern hemisphere? a. Glossopteris c. Panthalassa b. Gondwanaland d. Mesosaurus 18. The study of the Earth’s magnetic field and magnetic properties in the geologic past is known as a. magnetology. c. gravitational anomalies. b. paleomagnetism. d. magnetizationism. 19. When basalt’s temperature falls below 580 degrees Celsius, the crystals become magnetized in the Earth’s magnetic field. This point is called a. magnetic point. c. Curie temperature. b. peak temperature. d. magnetization. 20. The type of boundary that occurs when plates move sideways past one another, such as the San Andreas Fault in California, is called a. convergent boundary. c. divergent plate boundary. b. shear (transform) boundaries. d. trailing edge. Fill in the Blank 1. A compressional seismic body wave is called . 2. The seismic body wave that does not pass through fluids is called . 3. The discontinuity that marks the boundary between the mantle and the outer core is the ____________ . 4. The mantle is composed predominantly of iron and magnesium silicate minerals represented by the igneous rock . 5. Shear stress will often result in the formation of . 6. The temperature above which a substance is no longer magnetic is called the ________ _____________. The type of fault in which the relative motion of the hanging wall with respect to the foot wall is down is called a . 8. Splinters of the oceanic plate that are scraped off the upper part of a descending oceanic plate and welded onto the forward edge of the overriding continental plate is called _____________ . 9. Plate movement is on a weak, partially molten region of the upper mantle called the . . 10. In Alfred Wegener’s theory of continental drift, the supercontinent included in all of present day major continental masses is called . 11. That portion of the supercontinent that separated and formed North America and Eurasia came to be called . 12. Large-motion waves that travel through the outer crust of the Earth are called _________ ________. 13. _________________ is a condition of vertical balance or “floating depth.” 14. _________________ are uparched rocks (think of McDonald’s “Golden Arches”). 15. Plates move apart at _____________ _______________ _______________ which may manifest as mid-oceanic ridges complete with tensional geologic structures. True/False 1. Primary and secondary waves (body waves) pass deep within the Earth and are responsible for most of the destructive effects. 2. The seismic boundary that separates the mantle from the overlying crust is the Mohorovicic discontinuity. 3. Sudden changes in earthquake wave velocities are termed unconformities. 4. The Wadati Benioff Seismic Zone is associated with frequent earthquake activity and marks the location of the plunging forward edge of the lithosphere. 5. Below the Curie temperature, magnetic characteristics of the mineral are altered. 6. The approximate age of the oldest sediments on the seafloor are approximately 500 million years old. 7. The underlying surface of an inclined fault plane is called the hanging wall. 8. In general the rocks of the ocean floor are younger and less complex than those found on the continents. 9. The great Permo-Carboniferous southern hemisphere continent Gondwana comprised the assembled continents of South America, India, Australia, Africa, Arabia and Antarctica. 10. The velocity of plate movement is uniform round the world. Answer Key Multiple Choice a b a b a d a d b d b d b c c b d b c b Fill Ins P-wave S-wave Gutenburg discontinuity peridotite strike-slip-faults Curie point normal fault ophiolite suites asthenosphere Pangea Laurasia surface waves Isostasy Anticlines divergent plate boundaries True/False F T F T F F F T F F RESPONSES TO QUESTIONS ACCOMPANYING SELECTED FIGURES FIGURE 7–1 (p. 170) Surface waves are most likely to cause the most damage. FIGURE 7–5 (p. 173) The Gutenberg discontinuity marks the boundary between the outer core and the mantle. The average density of the layers of the Earth increases from the crust to the mantle, to the outer core to the inner core. FIGURE 7–6 (p. 173) Seismograph stations located in Buenos Aires would not receive secondary waves from an earthquake with an epicenter at the North Pole. FIGURE 7–7 (p. 174) Meteorites are easier to collect in Antarctica than in warmer parts of the Earth because the dark-colored meteorites are easier to see against the white background of snow and ice. FIGURE 7-12 (p. 177) Because of seafloor spreading, volcanoes far from the ridge have been transported from their place of origin and subsided as they were being conveyed away. The oceanic crust itself slowly subsides as it is conveyed away from the spreading center. Because they are older than volcanoes currently forming at the spreading center, volcanoes far from the ridge have experienced more erosional loss. FIGURE 7–31 (p. 190) The San Andreas Fault is a right lateral fault. It can also be termed a transform fault. FIGURE 7-39 (p. 196) The southward-trending arm known as the East African rift is the aulacogen in the Afar Triangle. FIGURE 7–41 (p. 197) The oldest magnetically reversed bands are the outermost bands on either side. FIGURE 7–45 (p. 199) The ocean floor was conveyed about 580 kilometers along line A-A’ between 81 and 53 million years ago. FIGURE 7–46 (p. 199) The Pacific Ocean region generally has faster moving plates. FIGURE 7–57 (p. 206) Normal faults are not the result of compressional forces. FIGURE 7–58 (p. 207) Movement across the fault line on the opposite block shows that the movement has been to the right. FIGURE 7–59 (p. 207) It is a normal fault. Note the yellow bed marker has moved down. FIGURE 7–63 (p. 208) A structural dome (the Ozark Dome) underlies southern Missouri. Other nearby uparched structures (colored purple) include the Cincinnati Arch to the northeast of Missouri and the Nashville Dome centered in Tennessee. FIGURE 7–65 (p. 209) From the outermost limbs of the anticline to the axial plane, strata would be increasingly younger in age. FIGURE 7–66 (p. 211) Streams are confined to the beds of less resistant rock (probably shales) areas exposed between ridges composed of resistant strata.