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Geol 101: Physical Geology
EXAM 3
Fall 2002
Write your name out in full on the scantron form and fill in the corresponding ovals to spell out
your name. Use a pencil! Fill in your student ID number in the space provided. Do not include
the dash and do not leave any spaces. Make sure you have all 8 pages of the exam.
1. Which of these geologic sequences is in the correct order for Palouse area (from oldest to
youngest)?
A. Idaho Batholith granite - Belt rocks - Columbia River flood basalts - Lewiston fold
B. Belt rocks – Lewiston fold - Columbia River flood basalts - loess deposits
C. Belt rocks - Columbia River flood basalts - Idaho Batholith granite - Missoula flood
D. Columbia River flood basalts – Lewiston fold - Bonneville flood - Missoula flood
E. loess deposits - Columbia River flood basalts - Idaho Batholith granite - Belt rocks
2. Granite Point, along the Snake River, is actually not granite but (1) _________ and contains
the minerals (2) ____________.
A. (1) basalt; (2) feldspar and pyroxene
B. (1) basalt; (2) feldspar and biotite
C. (1) gneiss; (2) quartz, feldspar, and olivine
D. (1) gneiss; (2) quartz, feldspar, and orthoclase
E. (1) gneiss; (2) quartz, feldspar, and biotite
3. Columns formed inside Columbia River Basalt lava flows because:
A. they erupted underwater
B. they have been exposed to weathering for 16 million years
C. the lava contracted as it cooled, forming joints
D. the lava dried out, just like mudcracks
E. the formation of the Lewiston fold disrupted the lava flows
4. Which evidence below proves that the Missoula flood happened after the Bonneville flood?
A. Bonneville flood deposits formed an island that sits high above the waterline
B. the Missoula flood happened because an ice dam burst
C. Missoula flood deposits are still unconsolidated
D. the Missoula flood flowed upstream along the Snake River
E. Bonneville flood deposits are underneath the Missoula flood deposits
5. During the Cretaceous, plate motions and subduction along the west coast of North America
resulted in:
A. microcontinents colliding with North America, forming Oregon and Washington
B. intrusion of the Idaho batholith due to partial melting of subducting oceanic crust
C. eruption of the Columbia River flood basalts
D. both A and B above
E. all of the above
6. 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 waves pass across the boundary unchanged
C. some of the waves get reflected
D. some of the wave rays get refracted
E. both C and D above
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7. We know that the outer core is a liquid because:
A. an S-wave shadow zone is produced by the S-waves being stopped dead
B. a P-wave shadow zone is formed
C. S-waves get refracted through the outer core
D. P-waves get reflected off of the inner core boundary
E. S-waves pass into the outer core but cannot get out again
8. The Moho is the boundary between:
A. the inner core and the outer core
B. the mantle and the outer core
C. the lithosphere and the asthenosphere
D. the crust and the mantle
E. the lithosphere and the low-velocity zone
9. The reason the Earth is able to have plate tectonics is:
A. the asthenosphere is soft and gooey so the plates can move around on top of it
B. the lithosphere is brittle so it has been able to break apart to form the plates
C. convection in the mantle provides a driving force to move the plates around
D. subduction of old crust makes room for new crust forming at mid-ocean ridges
E. all of the above
10. The Earth has a magnetic field because:
A. the liquid outer core creates an electric current which induces a
magnetic field
B. magnetic minerals are common at temperatures above the Curie point
C. it has a magnetic iron-nickel core
D. all planets have magnetic fields when they form
E. something about a giant domino
11. How old is the oldest oceanic crust currently found under the oceans?
A. as old as the Earth itself
B. 10 million years
C. 180 million years
D. 3.8 billion years
E. 4.6 billion years
12. The reason for the age of the oldest oceanic crust in your answer to question 11 is:
A. oceanic crust has been forming since the Earth first formed
B. oceanic crust has only been forming for 4% of Earth history
C. all older oceanic crust got subducted back into the mantle long ago
D. continents plowed through all the older oceanic crust because of plate tectonics
E. we haven’t looked hard enough for older oceanic crust
13. Moving away from a continent, the order of features comprising the continental margins is:
A. shelf – slope – rise
B. shelf – rise – slope
C. slope – shelf – rise
D. slope – rise – shelf
E. rise – slope – shelf
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14. The edge of the continental shelf:
A. is somewhere beneath the continental slope
B. is the true edge of the continents
C. is always about the same distance away from the coastline
D. is marked by an almost vertical drop-off into the deep ocean basin
E. is consistently at a water depth of about 135 meters
15. The west coast of North America is a/an (1) __________ continental margin because
(2) ___________.
A. (1) active (2) it is right along a tectonic plate boundary
B. (1) active (2) it is far from a tectonic plate boundary
C. (1) passive (2) it is right along a tectonic plate boundary
D. (1) passive (2) it is far from a tectonic plate boundary
E. (1) passive (2) it is characterized by earthquakes and volanoes
16. The deepest
A.
B.
C.
D.
E.
part of all ocean basins is:
the continental shelf
the abyssal plains
the ocean trenches
the ocean ridges
somewhere beneath the continental slope
17. 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) Pangea (2) Gondwana (3) Eurasia
D. (1) Gondwana (2) Laurasia (3) Pangea
E. (1) Gondwana (2) Pangea (3) Laurasia
18. Which of the following is good evidence that South America and Africa were once joined
together?
A. they both show evidence of an ice age during the Carboniferous Period
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. all of the above
19. Evidence that North America used to be connected to Europe is given by the fact that the
following two mountain chains seem to match up from one continent to the other:
A. Rockies and Caledonides
B. Appalachians and Caledonides
C. Rockies and Himalayas
D. Appalachians and Himalayas
E. Appalachians and Alps
20. Africa and South America both show fossil evidence of a type of freshwater reptile called:
A. Simonsaurus
B. Glossopteris
C. Tyrannosaurus
D. Mesosaurus
E. Barney
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21. North America and Europe seem to show different paleomagnetic north pole locations for similaraged rocks. The reason for this is:
A. there was more than one north pole when these rocks formed
B. the pole was wandering around so the paleomagnetic record is inaccurate
C. North America and Europe used to be together, so the poles are actually the same
D. the rocks on each continent cannot be similar in age, as was originally thought
E. the true edge of the continents is somewhere beneath the continental slope
22. As a result of seafloor spreading at a mid-ocean ridge, the following is true:
A. rocks on one side of the ridge have the opposite magnetic polarity to the other side
B. Earth’s magnetic field reverses about every half million years
C. older oceanic crust is slowly pushed away from ridge
D. continents plow through the oceanic crust
E. all of the above
23. The oldest oceanic crust occurs (1) ________ and the youngest occurs (2) __________.
A. (1) at mid-ocean ridges (2) along subduction zones
B. (1) at mid-ocean ridges (2) along the continental margins
C. (1) along the continental margins (2) at mid-ocean ridges
D. (1) along the continental margins (2) along subduction zones
E. (1) somewhere beneath the continental slope (2) at mid-ocean ridges
24. The fastest moving mid-ocean ridge spreading center is:
A. the mid-Atlantic ridge
B. the East Pacific Rise
C. the Juan de Fuca ridge
D. the Cascadia subduction zone
E. the Himalayas
25. 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
26. Which of the following locations would be expected to exhibit normal faults?
A. the East African Rift Valley
B. the mid-Atlantic ridge
C. divergent plate boundaries
D. all of the above
E. none of the above
27. The three types of convergent 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
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28. What type of plate boundary may be associated with a suture zone?
A. ocean-ocean boundary
B. ocean-continent boundary
C. continent-continent boundary
D. transform boundary
E. all plate boundaries have suture zones
29. The top of Mt. Everest exhibits (1) __________ which indicates that (2) ___________.
A. (1) metamorphism (2) it must be a continent-continent plate boundary
B. (1) isostacy (2) it must be less dense than the underlying mantle
C. (1) slow upward motion through time (2) it sits on top of a hot spot
D. (1) sea shell fossils (2) it used to be the ocean floor but got uplifted
E. (1) glacial features (2) it used to be near the south pole
30. An example of a transform fault that comes partly on-land is:
A. the San Andreas fault
B. the Lost River fault
C. the mid-Atlantic ridge
D. the Denali fault
E. Baja California
31. Which of the following are effective agents of erosion?
A. water
B. gravity
C. wind
D. ice
E. all of the above
32. What is meant by saltation?
A. where evaporation of water causes salt crystals to grow
B. it is a type of erosion caused by rivers
C. when particles of sand slide down the front of a ripple or dune
D. where sediment particles bounce along the ground due to wind or water
currents
E. it is a type of erosion caused by wind blowing sediment against a rock surface
33. The cohesiveness of sediment is defined as:
A. the steepest angle of slope that the sediment is able to maintain
B. the resistance to downslope motion of sediment
C. the degree to which the sediment has been lithified into rock by diagenesis
D. how well the sediment particles stick together
E. how much water is present within the sediment
34. The steepest slope that can be produced by a pile of unconsolidated sediment is called the:
A. angle of criticality
B. angle of concern
C. angle of repose
D. angle of mass wasting
E. angle of cohesion
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35. All air-saturated sediment flows are called (1)______ whereas all water-saturated sediment
flows are called (2)_________:
A. (1) granular flows (2) slurry flows
B. (1) unconsolidated flows (2) slurry flows
C. (1) debris flows (2) mudflows
D. (1) slurry flows (2) viscous flows
E. (1) slurry flows (2) granular flows
36. Which of the
A.
B.
C.
D.
E.
following processes describes water seeping into the ground?
infiltration
evaporation
condensation
transpiration
precipitation
37. About 99% of all liquid fresh water on Earth is stored:
A. in the oceans
B. in swamps
C. in the ice caps
D. underground
E. in rivers
38. Which of the following reservoirs has the shortest residence time for water molecules?
A. oceans
B. rivers
C. ice sheets
D. atmosphere
E. the human body
39. Which of the following features or processes is NOT associated with a meandering stream?
A. anastomosing flow
B. point bars
C. oxbow lakes
D. cut banks
E. lateral accretion
40. All sediment
A.
B.
C.
D.
E.
deposited by rivers is called:
regolith
point bar deposits
bed load
alluvium
delta deposits
41. Which of the following features or processes would NOT be associated with a floodplain?
A. natural levees
B. distributaries
C. stream terraces
D. point bars
E. vertical accretion
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42. The type of delta that forms the classic delta shape () when viewed from above is called a:
A. bird’s foot delta
B. tide-dominated delta
C. stream-dominated delta
D. wave-dominated delta
E. tri-delt
43. Rivers that flow into larger rivers are called (1)________ whereas rivers that flow across the
surface of a delta are called (2)________.
A. (1) distributaries (2) tributaries
B. (1) distributaries (2) natural levees
C. (1) tributaries (2) distributaries
D. (1) tributaries (2) stream-dominated
E. (1) drainage divides (2) distributaries
44. Which of the following is NOT a local base level along a river?
A. lake
B. sea level
C. waterfall
D. dam
E. all of the above are local base levels
45. A drop in ultimate base level can produce _______ on a floodplain.
A. downcutting
B. incised meanders
C. stream terraces
D. headward erosion
E. any of the above
46. The average
A.
B.
C.
D.
E.
amount of time between floods of a certain discharge level is called the:
repeat time
flood interval
recurrence interval
100-year flood
disaster preparedness allocation
47. Sediment near the Earth’s surface only has air inside the pores, so it is called the:
A. vadose zone
B. unsaturated zone
C. zone of aeration
D. all of the above
E. none of the above
48. The amount of water that a rock can store is determined by the (1) ________ whereas the
ability of a rock to transmit water through it is called the (2) _________.
A. (1) density (2) head gradient
B. (1) permeability (2) porosity
C. (1) permeability (2) infiltration capacity
D. (1) porosity (2) infiltration capacity
E. (1) porosity (2) permeability
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49. A well dug into an unconfined aquifer will:
A. fill up with water to the level of the water table
B. dry up during the dry season
C. immediately develop into an artesian well
D. develop a cone of depression around the well
E. need to pierce through an aquicude to reach the aquifer
50. Which of the following is NOT associated with overpumping of a well?
A. artesian well
B. saltwater incursion
C. compaction
D. subsidence
E. cone of depression
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. because of the UFOs hovering above
52. If you are standing in an arid or semi-arid region looking at the features around you
produced by running water, which of the following features might you see?
A. braided streams
B. bars
C. bajadas
D. alluvial fans
E. all of the above
53. What type of mass wasting is the Lewiston slide?
A. mudflow
B. slump
C. rockfall
D. debris avalanche
E. creep
54. Island arc volcanoes form:
A. whenever subduction occurs
B. when a continent subducts underneath another continent
C. at ocean-ocean plate boundaries
D. along the Cascadia subduction zone
E. somewhere beneath the continental slope
55. Where did a
A.
B.
C.
D.
E.
M7.9 earthquake occur in the United States 10 days ago?
Missouri
California
Alaska
Utah
Washington
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