KEY CHAPTERS 9-11 TAKE-HOME QUIZ INTERNAL STRUCTURES AND PROCESSES Score Part A = / 88 PART A

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1 GEOLOGY 12 KEY CHAPTERS 9-11 TAKE-HOME QUIZ INTERNAL STRUCTURES AND PROCESSES Score Part A = / 88 PART A Read each question carefully and chose the BEST answer. Mark and correct your answers before asking for the workbook for this unit. CHAPTER 9 Plate Tectonics 1. All of the following are characteristic of divergent boundaries EXCEPT: a. transform faults b. rifting c. volcanic activity d. island arcs 2. The Red Sea a. formed from continental rifting. b. is a shallow sea that is slowly disappearing due to convergence. c. was formed following the Pleistocene due to a dam consisting of ice-deposited sediment. d. Is an intraplate sea. 3. Iceland is an example of a(n) a. above sea-level expression of a divergent boundary. b. stalled convergent boundary. c. intraplate hot spot. d. extinct volcano. 4. The best possible explanation for the driving force for plate movement is a. convection in the asthenosphere. b. convection deep in the mantle. c. the downward pull of gravity on down-going slabs of lithosphere in subduction zones. d. a combination of all of the above. 5. Mountain ranges are produced at a. divergent plate boundaries. b. convergent plate boundaries. c. parallel plate movement. d. intraplate fault zones. 6. If the age of rock samples were found to be at increasing distance from spreading centers, we would find the a. older rocks closer to the spreading center. b. younger rocks closer to the spreading center. c. older rocks farther from the spreading center. d. both b and c. 7. Supporting evidence for continental drift includes all of the following EXCEPT: a. matching of continental edges b. the existence of transform faults c. finding equatorial fossils in northern regions d. polar-wander curves

2 The average thickness of the oceanic lithosphere is kilometers. (a) 5 (b) 50 (c) 500 (d) 5, The weak or plastic zone just below the brittle plates is the (a) asthenosphere (b) lithosphere (c) crust (d) mantle 10. Magnetic minerals in a magma a. tend to align themselves parallel to the earth s magnetic field b. all have the same Curie temperature c. cause magma to flow toward the magnetic poles d. all of these choices 11. The magnetic stripes of the seafloor a. record the recent reversal history of the earth s magnetic field b. show a symmetric pattern on either side of a spreading ridge c. are created as magma crystallizes at ridges d. all of these choices 12. The oldest rocks recovered from the seafloor are about years old. a. 200 b. 200,000 c. 200 million d. 2 billion 13. All of the following are characteristic of convergent plate boundaries EXCEPT a. subduction zones b. earthquakes c. transform faults d. island arcs 14. A hot spot is a. an isolated area of active volcanism, especially one away from a plate boundary b. an area of intensive earthquake activity c. an area in which subduction is causing partial melting d. a zone of continent-continent collision 15. The rate and direction of plate movements can be determined using a. ages of seafloor rocks at various distances from a spreading ridge b. polar-wander curves c. hot spots d. all of these choices. 16. A possible driving force for plate tectonics is a. magnetic reversals b. convection in the asthenosphere c. convection in the lithosphere d. polar wandering 17. Studies of past plate motions indicate that a. any two adjacent plates must move in the same direction, to avoid plates breaking up b. once they begin to move, plates always continue to move in the same direction c. plate movements have occurred for hundreds of millions, probably billions, of years d. all of these choices

3 The rocks of the continents are recycled into the mantle by a. continent-continent collision b. weathering and subduction of sediments c. metamorphism in the lithosphere d. seafloor subduction 19. The orientation of the Hawaiian Island group a. shows the direction of movement of the Pacific Plate b. is a function of a rift zone c. is defined by the edge of the Pacific Plate d. has no significance 20. Two centimeters of continental drift per year for 100 million years a. would amount to 2,000 kilometers b. would amount to 4,000 kilometers c. is highly unlikely to have occurred in the geologic past d. would be an insufficient amount of plate movement to allow reconstruction of Pangaea. 21. Rates of plate movement can be determined by using a. radiometric dating of seafloor rocks around spreading ridges b. mantle hot spots c. mantle hot spots and radiometric dating of seafloor rocks around spreading ridges d. none of these choices 22. Which of the following are associated with subduction zones? a. earthquakes b. volcanoes c. island arcs d. all of these choices 23. The San Andreas Fault is an example of a a. subduction fault b. rotating fault c. divergent margin d. transform fault 24. The Curie temperature of a magnetic mineral is a. above the melting point of that mineral b. the same as the melting point of that mineral c. the temperature above which magnetic properties are lost d. the same for all magnetic minerals 25. Magma escaping from a rift valley eventually cools and forms basaltic rock, which is a. reversely magnetized b. normally magnetized c. magnetized in the prevailing direction of the earth s magnetic field d. magnetized 90 degrees from the prevailing direction of the earth s magnetic field 26. The average depth of the asthenosphere is about a. 250 kilometers b. 25 kilometers c. 5,000 kilometers d. 50 kilometers

4 27. The layer above the asthenosphere is the a. upper mantle b. stratosphere c. lithosphere d. ionosphere 28. Climatic evidence for continental drift a. includes the fact that ancient climates appear to have been very different from the current climate of the same region b. is, in part, based on the types of sedimentary rocks that formed in the past c. considers types of plant fossils found in sedimentary rocks d. all of these choices 29. Polar-wander curves indicate a. the apparent movement of the magnetic poles relative to a continent through time b. the actual movement of the magnetic poles through time c. the predicted movement of the magnetic poles in future years d. none of these choices A mid-ocean spreading ridge is associated with a. a divergent plate margin b. a convergent plate margin c. a transform boundary d. intraplate mantle hot spots 31. Evidence for seafloor spreading includes a. the age distribution of seafloor rocks b. magnetic stripes on the ocean floor c. magnetic stripes on the ocean floor and the age distribution of seafloor rocks d. none of these choices 32. Rates of spreading at seafloor ridges are usually in the range of a a. few meters per year b. centimeter per million years c. few centimeters a year d. centimeter per thousand years CHAPTER 10 Earthquakes 33. The elastic rebound theory: a. explains folding of rocks. b. explains the gradual accumulation and release of stress and strain in rocks. c. explains the origins of earthquakes. d. none of these. 34. The point within the Earth where seismic waves originate is: a. the epicenter. b. the fault scarp. c. the origin. d. the focus.

5 P-waves are: a. transverse surface waves. b. compressional body waves. c. tensional surface waves. d. shearing body waves. 36. The minimum number of seismic stations needed to locate an earthquake is: a. 8 b. 2 c. 3 d The Richter Scale is used to determine: a. intensity of earthquakes. b. the magnitude of earthquakes. c. the damage from earthquakes. d. the number of casualties in an earthquake. 38. Benioff Zones are associated with: a. mid-ocean ridges b. ancient mountain chains c. subduction zones d. all of these. 39. Most earthquakes at divergent plate boundaries are: a. shallow focus b. intermediate focus c. deep focus d. all of these. 40. Most earthquakes at convergent boundaries are: a. shallow focus. b. intermediate focus. c. deep focus. d. all of these. 41. Shallow earthquakes along the faults of a fracture zone are typical of: a. divergent plate boundaries. b. convergent plate boundaries. c. transform plate boundaries. d. none of these. 42. Which of the following is characteristic of a tsunami? a. very long wavelength. b. very fast moving. c. very low amplitude in the open ocean. d. all of these. 43. The fastest seismic waves are: a. P-waves b. S-waves c. Love Waves d. Rayleigh Waves

6 The first seismic waves to arrive at a seismic station are: a. P-waves b. S-waves c. Love waves d. Rayleigh waves 45. Analysis of seismograph records cannot provide information on: a. the magnitude of the earthquake. b. the location of the earthquake. c. the number of fatalities in an earthquake. d. the depth of the earthquake. 46. The behavior of water-saturated soil during an earthquake is known as: a. liquefaction. b. quick sand. c. gelatinization. d. none of these. 47. Among the secondary effects of large earthquakes are: a. tsunamis. b. fires. c. landslides. d. all of these. 48. Which of the following areas is most likely to experience a large magnitude earthquake? a. Western Canada. b. Arctic Canada. c. Eastern Brazil. d. Southern Australia. 49. Stress that tends to pull material apart is a. compressive b. tensile c. shear d. brittle 50. Material that ruptures under stress before it has undergone much deformation is described as a. brittle b. plastic c. elastic d. weak 51. Slow, continuous movement along a fault zone is termed a. elastic rebound b. creep c. dilatancy d. stress 52. Earthquakes occur a. when rocks rupture under stress b. when rocks deform plastically under stress c. only when large faults at plate boundaries move d. all of the above

7 A seismic gap is a. an area that has no faults in it b. a fault that has not been active in historic times c. a locked section along an active fault zone d. an earthquake-prone region well away from a plate boundary 54. The concept that in stressed rocks, cracks and pores open up, then fluids seep in before the rocks slip in an earthquake, is termed a. fluid injection b. dilatancy c. precursors d. liquefaction 55. The magnitude of an earthquake is the measurement of the a. ground motion b. ground displacement c. ground shaking d. energy released 56. Most earthquakes are - focus. a. shallow b. deep 57. Deep-focus earthquakes occur only a. at transform faults b. in subduction zones c. at spreading ridges d. all of the above 58. Earthquake epicenters are located using the a. time of first arrival of P-waves after an earthquake b. time of first arrival of S-waves c. time of first arrival of surface waves d. difference in arrival times of P-waves and S-waves 59. The distance to the epicenter of an earthquake can be measured by the Travel-Time Curve. This is the measurement of the a. time of arrival of the P-wave to a seismograph. b. time of arrival of the S-wave to a seismograph. c. difference in the time of arrival of the P-wave and S-wave d. a and b CHAPTER 11 Earth s Interior 60. Earthquakes generate P and S waves. A seismograph located on the opposite side of the earth from a major earthquake will detect only one of these types of waves. This is because a. P waves will not pass through the core b. S waves will not pass through the core c. P and S waves interfere with each other d. S waves are refracted by the dense interior

8 The fact that there is a zone that receives no P and no S waves indicates an internal layer of the earth where a. both the P and S waves are absorbed b. both the P and S waves are refracted c. the P waves are refracted and the S waves are absorbed d. the P waves are absorbed and the S waves are refracted. 62. Xenoliths in volcanic rocks provide samples of a. the deep crust b. the upper mantle c. the lower mantle d. all the above 63. Information on the relative cosmic abundance of the rarer elements is obtained primarily from analysis of a. the earth b. the sun c. meteorites d. other stars 64. The overall mass and density of the earth indicate that a. it is homogeneous in chemical composition throughout b. there must be very dense material in the interior c. there are three major zones in the interior d. all the above 65. The Moho discontinuity is the boundary between the a. P-wave and S-wave shadow zones b. core and mantle c. lithosphere and asthenosphere d. crust and mantle 66. The low-velocity layer is in the (see Fig p.231) a. outer core b. crust c. asthenosphere d. lower mantle 67. The internal structure of the Earth can best be determined by a. test drilling into the core b. taking samples from volcanoes c. studying the refraction of earthquake waves d. looking at cross sections of sedimentary rocks 68. Which of the following is NOT true of the outer core? a. it is molten b. the earth's magnetic field can be explained by fluid motions in it c. it size is estimated from the size of its seismic shadow d. it is similar in composition to the mantle, but is slightly less dense 69. The speed of earthquake waves as they cross the Moho a. increases b. decreases c. falls to zero d. does not change

9 Information about the core of the earth is gained from analyzing a. drill hole samples b. earthquake waves c. uplift fault blocks d. magma composition 71. Proceeding towards the centre of the earth, rock material becomes a. hotter b. less mafic c. less dense d. more brittle 72. The layer of the earth which is the most solid and brittle is the a. core b. mantle c. lithosphere d. asthenosphere 73. Which of the following is the most common element in the Earth's crust a. iron b. silicon c. oxygen d. aluminum 74. Body waves travel faster deep within Earth than near the surface. In which layer of the Earth would earthquake waves travel the fastest? a. Moho b. oceanic crust c. lower mantle d. asthenosphere 75. Which of the following elements is a major component of the earth's core a. aluminum b. potassium c. oxygen d. iron 76. The average thickness of the Earth's mantle as compared to the average thickness of the continental crust is approximately a. ten times thicker (~300 vs ~3000km) b. one hundred times thicker c. two times thicker d. one thousand times thicker 77. The asthenosphere behaves a. plastically b. elastically c. as a liquid d. rigidly 78. The lower mantle is not believed to contain any sharp compositional changes because seismic velocities (see Fig p. 233) a. are uniform in this zone b. decrease abruptly in this zone c. increase gradually in this zone d. none of these choices

10 A core that consists mostly of iron may account for the earth's magnetic field because a. a magnetic field could be generated by flow of the molten iron within the outer core b. the temperature of the earth's interior is beyond the Curie temperature of iron. d. the earth's gravitational forces would disorient the poles at the equator d. none of these choices 80. Kimberlites a. are diamond-bearing ultramafic rocks b. originate at depths of approximately 200 kilometers c. occur as volcanic pipes on some continents d. all of these 81. The correct sequence of the Earth's internal structure is a. crust, mantle, Moho, core b. Moho, crust, mantle, core c. mantle, Moho, crust, core d. crust, Moho, mantle, core 82. Complete the following questions in the space provided. (7 marks) Label the parts of the earth's interior layers indicated by the arrows in the drawing below. The question marks indicate the possible pathways of seismic waves through the Earth. Does A or B indicate the Primary Wave pathway? B Crust Mohorovicic discontinuity Mantle Gutenberg discontinuity Outer core Inner core

11 GEOLOGY 12 KEY CHAPTERS 9-11 TAKE-HOME QUIZ INTERNAL STRUCTURES AND PROCESSES Score Part A = / 88 PART A PART B CHAPTER 12 Isostacy and Structural Geology 1. Using the terms below, label the following diagrams and place arrows on the drawings that show relative movement of the hanging wall and footwall. normal fault reverse fault thrust fault Normal Fault Thrust Fault Reverse Fault 2. Brittle rocks tend to _RUPTURE_ in response to stress. 3. Fractures in rock along which there is no movement or displacement are called JOINTS. 4. Fractures in rock along which movement has occurred are known as FAULTS. 5. When geologist talk about the STRIKE of a rock layer, they refer to a compass direction measured parallel to the earth's surface. 6. When geologist talk about the DIP of a rock layer, they mean the tilt or angle of the layer, measured down from the horizontal plane. 7. If a geologist said that a dike was oriented N35 E, s/he would be telling you the STRIKE of the dike. 8. Which type of faulting commonly occurs as a result of tensional (pulling apart) stresses. a. reverse fault b. normal fault c. thrust fault d. strike-slip fault 9. Faults which show vertical motion are described as a. dip-slip faults b. oblique faults c. thrust faults d. strike-slip faults

12 From the view of an observer facing a strike-slip fault, the displacement across the fault is such that features appear to have shifted to the left. What specific type of fault is this? a. reverse fault b. normal fault c. right-lateral fault d. left-lateral fault 11. If the hanging wall has moved up relative to the footwall, the fault is REVERSE. 12. If the hanging wall has moved down relative to the footwall, the fault is NORMAL. 13. A reverse fault with a very low angle plane is called a THRUST fault. Use Figures 1-4 below to answer questions #14 to Referring to Fig. 1 feature "A" is called the STRIKE 15. Referring to Fig. 1 feature "B" is called the DIP 16. Referring to Fig. 2, which side of the fault is the hanging wall? A 17. Referring to Fig. 2, which side of the fault is the footwall? B 18. Referring to Fig. 2, which side of the fault moved UP relative to the other? A 19. Referring to Fig. 2, what specific type of dip-slip fault is shown? _REVERSE FAULT_ 20. Referring to Fig. 3, which side of the fault is the hanging wall? B 21. Referring to Fig. 3, which side of the fault is the footwall? A 22. Referring to Fig. 3, which side of the fault moved down relative to the other? B 23. Referring to Fig. 3, what specific type of dip-slip fault is shown? NORMAL FAULT

13 Referring to Fig. 4, what type of fault is pictured? STRIKE-LIP FAULT 25. Referring to Fig. 4, is this a left or right lateral fault? LEFT-LATERAL FAULT 26. Which of the following could be produced by compressional forces? a. reverse faults b. thrust faults c. overturned folds d. all of the above 27. Which one of the following faults would most likely be formed by tensional forces a. thrust b. normal c. reverse d. strike-slip 28. A transform fault is also a a. joint set b. strike-slip fault c. dip-slip fault d. oblique-slip fault 29. In a reverse fault the a. older rock may be pushed over younger rock b. hanging wall move down relative to the footwall c. blocks slip horizontally d. forces involved are in tension rather than compression 30. A fault along which there is only horizontal movement is called a a. thrust b. normal c. reverse d. strike-slip 31. A fault along which there is movement in both the horizontal and vertical directions is called a. transform fault b. strike fault c. reverse fault d. oblique-slip fault 32. Crustal thickening can be caused by all of the following except a. thrust faulting b. recumbent folding c. reverse faulting d. normal faulting 33. A continent is in isostatic equilibrium. A large mountain range on the continent erodes away. In response, the base of the continental crust will a. rise b. sink c. not move d. melt 34. A folded structure which dips away from the centre in all directions is called a. a dome b. a basin

14 c. a syncline d. an anticline 35. By definition, in an anticline a. the limbs dip towards each other and the oldest rock are at the centre b. the limbs dip towards each other and the youngest rocks are at the centre c. the limbs dip away from each other and oldest rocks are at the centre d. the limbs dip away from each other and the youngest rocks are at the centre 36. In a syncline, the a. oldest rocks are in the core of the fold b. oldest rocks overlie younger units c. youngest rocks are in the core of the fold d. limbs dip away from each other 37. The mountain belt that forms the western part of North America is called the: a. Appalachian Mountains. b. Himalayas. c. North American Cordillera. d. Ouachita Mountains. 38. The craton: a. is the portion of a continent with the highest mountains. b. is the geologically stable portion of continents. c. is the youngest portion of continents. d. none of these. 39. Precambrian shields: a. are very ancient rocks representing the central cores of continents. b. have been destroyed by subduction over time. c. were once divergent plate margins. d. were in existence at the time Earth formed. 40. Folds and reverse faults in a mountain range suggest: a. compressional stresses. b. tensional stresses. c. deep-water deposition of sediments. d. all of these. 41. Which is not a type of terrane? a. exotic. b. suspect. c. accreted. d. accumulated. 42. Which of the following is a source of terranes? a. micro-continents. b. fragments of distant continents. c. ocean crustal fragments. d. all of these 43. A mountain belt formed through ocean-continent convergence may contain: a. fold and thrust belts.

15 b. thick accumulations of marine sedimentary rocks. c. high-grade metamorphic rocks. d. all of these. 44. The Himalayas, Appalachians, Alps and Ural Mountains formed as a result of: a. continent-continent convergence. b. ocean-continent convergence. c. ocean-ocean convergence. d. none of these. 45. The Andes Mountains of South America and the Cascade Range of North America formed as a result of: a. ocean-ocean convergence. b. continent-continent convergence. c. ocean-continent convergence. d. none of these. 46. It would appear that most mountain ranges form as a result of: a. some form of convergent tectonics. b. some form of divergent tectonics. c. some form of transform tectonics. d. none of these. Refer to the diagram below to answer questions #47 to What is the name of the type of fault labeled L? NORMAL FAULT 48. What type of forces (compressional, tensional or sheer) would have produced a fault of this type? TENSIONAL 49. What is the name of fold type K? SYNCLINE 50. At which type of PLATE BOUNDARY would fold type K most likely have been produced? CONVERGENT

16 In the space provided below, sketch and clearly label a cross section that contains an anticline cut by a reverse fault. (3 marks)