Geol 101: Physical Geology
EXAM 4
Spring 2002
Write your name out in full on the scantron form and fill in the corresponding ovals to spell out
your name. Also fill in your student ID number in the space provided. Do not include the dash and
do not leave any spaces.
There are 55 questions (8 pages). For each question, select the correct answer and fill
in your choice on the scantron form.
1. The average density of the Earth is 5.5 g/cm 3 whereas the average density of surface
rocks is 2.5-3.0 g/cm3. This tells us that:
A. the Earth is comprised of many layers with different densities
B. the deep interior of the Earth must have a density greater than 5.5 g/cm 3
C. the deep interior of the Earth must have a density less than 5.5 g/cm 3
D. the deep interior of the Earth must have a density less than 2.5 g/cm3
E. measurements of surface rock densities must be inaccurate
2. As seismic waves pass from a rock layer of a certain density to an adjacent rock layer with
a different density, the following is true:
A. the waves vanish at the interface between the two rock layers
B. the direction the wave is traveling changes
C. the wave rays get refracted
D. both B and C above
E. all of the above
3. The process whereby seismic waves bounce off a layer boundary back towards the surface is:
A. wave reflection
B. wave refraction
C. wave rays
D. wave interference
E. wave shadowing
4. A consequence of the outer core being liquid is:
A. the inner core is liquid
B. S-wave velocities decrease suddenly at the edge of the outer core
C. P-waves are unable to pass through the outer core
D. an S-wave shadow zone at greater than 103° away from an earthquake focus
E. a P-wave shadow zone at greater than 143° away from an earthquake focus
5. Which of the following statements is TRUE?
A. the boundary between the crust and the mantle is called the Moho
B. the boundary between the lithosphere and the asthenosphere is called the Moho
C. the average thickness of the crust under the oceans is 35 km
D. oceanic crust is thicker than continental crust
E. continents stand higher than ocean basins because of the principle of insanity
6. The Earth has
A.
B.
C.
D.
E.
a magnetic field because:
the liquid outer core creates an electric current which induces a magnetic field
magnetic minerals are common at temperatures above the Curie point
it has a magnetic iron-nickel core
all planets have magnetic fields when they form
magnetic minerals align themselves when they crystallize out of magma
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7. The difference between magnetic north and true north is called (1) ___________ whereas the
the angle between Earth’s magnetic field lines and the Earth’s surface is the (2) __________.
A. (1) magnetic deviation (2) magnetic inclination
B. (1) magnetic declination (2) magnetic reversal
C. (1) magnetic error (2) magnetic declination
D. (1) magnetic declination (2) magnetic inclination
E. (1) magnetic inclination (2) magnetic declination
8. The oldest oceanic crust beneath the oceans today is:
A. 4.6 billion years old
B. 3.5 billion years old
C. 180 million years old
D. 600 million years old
E. 6000 years old
9. The reason for the answer in question 8 is:
A.
B.
C.
D.
E.
there was no oceanic crust before that time
the ocean crust has not been studied in enough detail
all older oceanic crust long ago subducted back into the mantle
new crust is created at mid-ocean ridges
plate tectonics is a relatively recent geologic phenomenon on Earth
10. The correct order of features on the continental margins in the direction of increasing water
depth is:
A. continental shelf; continental rise; continental slope
B. continental slope; continental shelf; continental rise
C. continental slope; continental rise; continental shelf
D. continental rise; continental slope; continental shelf
E. continental shelf; continental slope; continental rise
11. Which of the
A.
B.
C.
D.
E.
following statements about ocean margins is FALSE?
the continental shelf width varies from place to place
the boundary between the continental shelf and slope is at a water depth of 135m
the continental slope is very stable and is not prone to underwater landslides
the edge of continental crust is somewhere below the continental slope
the average dip of the continental slope is about 4
12. Which of the
A.
B.
C.
D.
E.
following portion of the ocean floor is the flattest?
abyssal plains
ocean trenches
ocean ridges
continental slope
continental rise
13. The first line of evidence used to promote continental drift was that…
A. paleomagnetic fields are not consistent with the modern day magnetic field
B. the magnetic field underwent numerous reversals throughout Earth’s history
C. the continents seems to fit together like pieces of a jigsaw puzzle
D. lines of islands on moving plates formed above hotspots
E. scientists could tell that the continents are still moving today
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14. Plate tectonics theory suggests that the continents were once all combined into a supercontinent
called (1) _____, with the southern part called (2) _____ and the northern part called (3) ____.
A. (1) Pangea; (2) Laurasia; (3) Gondwana
B. (1) Pangea; (2) Gondwana; (3) Laurasia
C. (1) Laurasia; (2) Gondwana; (3) Pangea
D. (1) Gondwana; (2) Laurasia; (3) Pangea
E. (1) Gondwana; (2) Pangea; (3) Laurasia
15. Which of the following is NOT one of the lines of evidence that South America and Africa
were once joined together?
A. they both show evidence of tropical climates in the south during the
Carboniferous
B. the shapes of their coastlines are very similar
C. they have similar distributions of rocks that are about 550 million years old
D. they both contain fossils of a type of plant species called Glossopteris
E. they have similar-aged glacial evidence and consistent glacier flow directions
16. Modern day northern hemisphere continents have a lot of coal that is Carboniferous in age.
Keeping this in mind, which of the following statements is FALSE?
A. there were a lot of swampy areas during the Carboniferous
B. there was an ice age during the Carboniferous
C. the northern hemisphere continents were closer to the equator in the Carboniferous
D. the coal could have formed with the continents at their current latitudes
E. Laurasia and Gondwana had very different climates during the Carboniferous
17. Africa and South America both show fossil evidence of a type of freshwater reptile called:
A. Cynognathus
B. Glossopteris
C. Tyrannosaurus
D. Mesosaurus
E. Kattenhornus
18. We see bands of oceanic crustal rocks alongside mid-ocean ridges with alternating magnetic
polarity (paleomagnetism) because…
A. seafloor spreading occurs at mid-ocean ridges
B. Earth’s magnetic field reverses about every half million years
C. plate tectonics causes continents and ocean crust to slowly drift away from ridges
D. new ocean crust is constantly being created at mid-ocean ridges
E. all of the above
19. The oldest oceanic crust beneath the ocean basins occurs:
A. as ophiolites
B. along the continental margins
C. at mid-ocean ridges
D. in rift valleys
E. in the fastest spreading basins
20. Tectonic plates are made up of (1) ______ that floats on the underlying (2) _________.
A. (1) basalt (2) gabbro
B. (1) lithosphere (2) asthenosphere
C. (1) continental crust (2) mantle
D. (1) continental and oceanic crust (2) lithosphere
E. (1) lithosphere (2) outer core
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21. The three types of tectonic plate boundaries are:
A. normal, reverse, and strike-slip
B. active, passive, and extinct
C. divergent, convergent, and transform
D. seismic, volcanic, and subducting
E. ocean-ocean, ocean-continent, and continent-continent
22. An example of where a new ocean basin is trying to form is:
A. the East Africa Rift Valley
B. the mid-Atlantic ridge
C. Iceland
D. the Eastern Snake River Plain
E. the Himalayas
23. An island arc is a chain of volcanoes associated with (1) ______. An example is (2) _______.
A. (1) ocean-continent plate boundaries (2) the Phillipines
B. (1) ocean-continent plate boundaries (2) the Cascades
C. (1) ocean-ocean plate boundaries (2) the Cascades
D. (1) ocean-ocean plate boundaries (2) Japan
E. (1) hotspots (2) Hawaii
24. An example of a transform fault is:
A. the Cascadia subduction zone
B. the Seattle fault
C. the San Andreas fault
D. the New Madrid fault
E. the mid-Atlantic ridge
25. Which of the
A.
B.
C.
D.
E.
following resources is nonrenewable?
groundwater
coal
wind
solar energy
wood
26. How much of the world’s energy is obtained using nonrenewable resources?
A. 10%
B. 30%
C. 50%
D. 75%
E. 90%
27. Which of the
A.
B.
C.
D.
E.
following is NOT a type of hydrocarbon?
oil
coal
natural gas
tar
kerogen
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28. The correct sequence of events during the process of coalification is:
A. peat - lignite - bituminous coal - anthracite
B. lignite - peat - bituminous coal - anthracite
C. anthracite - lignite - bituminous coal - peat
D. peat - bituminous coal - lignite - anthracite
E. bituminous coal - lignite - anthracite - peat
29. The most viable source of energy that is an alternative to fossil fuels is:
A. solar energy
B. nuclear energy
C. biomass energy
D. hydroelectric energy
E. geothermal energy
30. Which of the following forms of harnessing energy does NOT involve driving a turbine?
A. nuclear power stations
B. hydroelectric power plants
C. geothermal power stations
D. tidal dam power plants
E. photovoltaic power technology
31. Which of the
A.
B.
C.
D.
E.
following statements about nuclear power is FALSE?
nuclear power is far more efficient than oil for generating energy
nuclear power plants create controlled fusion reactions to generate power
the radioactive decay of uranium-235 is the basis for producing nuclear energy
nuclear power supplies about 17% of the world's energy needs
a by-product of nuclear power generation is hazardous radioactive waste
32. What type of
A.
B.
C.
D.
E.
mineral deposits form as a result of weathering of existing deposits?
hydrothermal
placer
metamorphic
residual
sedimentary
33. “Any physical phenomenon that may impact on the surface of the planet, regardless of
whether or not it has a likelihood of causing damage or threatening society in any way”
refers to:
A. geologic risk
B. either geologic risk or geologic hazard
C. geologic hazard
D. rapid onset hazards only
E. slow geologic hazards only
34. Which of the following geologic phenomena does NOT constitute a geologic hazard?
A. avalanches
B. slumps
C. lahars
D. weathering
E. floods
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35. Which of the
A.
B.
C.
D.
E.
following examples constitutes the GREATEST geologic risk?
a tsunami along the coastline of the Pacific Northwest
a backcountry forest during peak fire season
a volcanic eruption on an uninhabited volcanic island
an earthquake in the middle of the Sahara desert
an avalanche in central Greenland
36. Which of the following actions is NOT considered to be a part of a geologic hazard
assessment?
A. creating a geologic hazard map
B. determining the history of a particular type of geologic hazard in a region
C. determining what the hazard would be like if it were to happen today
D. determining how often the hazard is likely to occur
E. determining how many people would be affected by the hazard
37. Which of the
A.
B.
C.
D.
E.
planets does NOT revolve in a counter-clockwise direction around the sun?
Venus
Earth
Mars
Jupiter
all planets revolve around the sun counter-clockwise
38. Which of the following statements is FALSE?:
A. all planets except Pluto revolve around the Sun in the plane of the ecliptic
B. Uranus is the only planet with a rotational axis pointing towards the Sun
C. the asteroid belt occurs between the planets Mars and Jupiter
D. all planets rotate in a counterclockwise direction when viewed from above
E. the Terrestrial planets consist of Mercury, Venus, Earth, and Mars
39. The meteorite impact that caused the extinction of the dinosaurs was the Chicxulub meteorite
that hit the (1) ______ about (2) _______ years ago.
A. (1) Arizona desert, USA (2) 49,000
B. (1) Arizona desert, USA (2) 66 million
C. (1) Yucatan Peninsula, Mexico (2) 66 million
D. (1) Yucatan Peninsula, Mexico (2) 49,000
E. (1) Tunguska region, Siberia (2) 66 million
40. About 93% of all meteorites fall into the category:
A. stony-iron
B. stony
C. iron
D. chondrites
E. carbonaceous chondrites
41. Which of the
A.
B.
C.
D.
E.
following planets does not have a core, mantle, and crust?:
Earth
Mercury
Neptune
Venus
Mars
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42. The largest meteorite impact crater, the largest volcano, and the largest rift valley in the solar
system can all be found on the planet:
A. Mercury
B. Mars
C. Venus
D. Io
E. Earth
43. The most volcanically active body in the solar system is:
A. Earth
B. Triton
C. the Moon
D. Io
E. Mars
44. Which of the following statements accurately accounts for why there were no advanced life
forms on Earth early in its geologic history?
A. initially the atmosphere contained mostly water vapor, CO 2 and nitrogen
B. oxygen is required but it was not abundant until about 2 billion years ago
C. eukaryotic cells are required but they could not develop until enough O was present
D. prokaryotic bacteria first needed to create enough O through photosynthesis
E. all of the above
45. The explosion of advanced life forms on Earth began about ________ years ago.
A. 4.6 billion
B. 3.5 billion
C. 2 billion
D. 600 million
E. 60 million
46. The evolutionary process called punctuated equilibrium supposes that:
A. creatures adapt to their environment and evolve through natural selection
B. evolutionary changes are ongoing and impercebtibly slow
C. sudden evolutionary changes are caused by rapid changes in the environment
D. different types of species interbreed to form a newer, more evolved species
E. most evolutionary changes are not adequately preserved in the fossil record
47. Which of the following is in the correct geologic order for the Palouse area (from oldest to
youngest)?
A. Idaho Batholith granite /Belt rocks /Columbia River flood basalts /loess deposits
B. Belt rocks /Idaho Batholith granite /Columbia River flood basalts /loess
deposits
C. Belt rocks /Columbia River flood basalts /Idaho Batholith granite /loess deposits
D. Columbia River flood basalts /Idaho Batholith granite /Belt rocks /loess deposits
E. loess deposits /Columbia River flood basalts /Idaho Batholith granite /Belt rocks
48. At Granite Point, relative age relationships between the gneiss and the basalt indicate that:
A. the basalt flowed over gneiss at the surface, forming a nonconformity
B. granite intruded into basalt and then both got metamorphosed
C. granite intruded into hot basalt, causing the granite to change into gneiss
D. basalt flowed over hot gneiss, creating an aureole in the basalt
E. the relative ages of the basalt and the gneiss cannot be determined
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49. The Missoula floods flowed in the (1) _______ direction along the Snake River and happened
(2) _______ the Bonneville flood.
A. (1) downstream; (2) before
B. (1) upstream; (2) after
C. (1) downstream; (2) after
D. (1) upstream; (2) before
E. it is not known which flood happened first
50. The Lewiston
A.
B.
C.
D.
E.
fold affects (1) _________ rocks and so must have formed (2) __________.
(1) Missoula and Bonneville flood deposits (2) less than 10,000 years ago
(1) Missoula and Bonneville flood deposits (2) at the end of the last ice age
(1) Columbia River flood basalt (2) less than 16 million years ago
(1) Columbia River flood basalt (2) more than 16 million years ago
(1) Columbia River flood basalt (2) along the Cretaceous subduction zone
BONUS QUESTIONS
51. A compass spins at the north pole because:
A. it is too cold for a compass to work properly
B. the magnetic declination changes through time
C. the magnetic field direction constantly reverses
D. the magnetic field is inclined vertically with respect to the surface
E. there is probably a UFO hovering overhead
52. The deepest point in all the world’s oceans is:
A. the mid-Atlantic ridge
B. the East Pacific Rise
C. the Marianas trench
D. the Cascadia subduction zone
E. off the coast of Hawaii
53. What can be found right at the top of Mt. Everest that supports the concept of plate tectonics?
A. fossil sea shells
B. ophiolites
C. mid-ocean ridge basalt
D. Glossopteris fossils
E. old oxygen cannisters
54. It would be difficult to have manned missions to Venus and Mars because:
A. neither planet has a magnetic field so it would be too easy to get lost
B. both planets are so small that there is only a small amount of gravity
C. both planets are extremely tectonically active, making it very dangerous
D. there is absolutely no indication of water being present on either planet
E. the surface of Venus is extremely hot and the surface of Mars is extremely cold
55. Attendance based question for those of you who were present in class on the day I told you
this. The answer to question 55 is:
A. ?
B. ?
C. ?
D. ?
E. ?
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