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GEOLOGY 12
CHAPTERS 9-11 TAKE-HOME QUIZ
INTERNAL STRUCTURES AND PROCESSES
PART A
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KEY
Score Part A = _______ / 88
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
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8.
The average thickness of the oceanic lithosphere is _______ kilometers.
(a) 5
(b) 50
(c) 500
(d) 5,000
9.
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
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18.
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
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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
30.
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.
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35.
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. 1
37.
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
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44.
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
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53.
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
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61.
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
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
(see Fig. 11.7 p.231)
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70.
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. 11.9 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
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79.
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
GEOLOGY 12
CHAPTERS 9-11 TAKE-HOME QUIZ
INTERNAL STRUCTURES AND PROCESSES
PART A
KEY
Score Part A = _______ / 88
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
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10. 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 25.
14. 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
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24. 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
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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.
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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 50.
47. 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____
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51. In the space provided below, sketch and clearly label a cross section that contains an anticline
cut by a reverse fault.
(3 marks)