Geol 101: Physical Geology
Summer 2007
EXAM 2
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. Make sure you
have all 8 pages of the exam. There are 55 questions. For each question, select
the correct answer and fill in your choice on the scantron form. You MUST use
pencil on the scantron form!
1.
Metamorphism differs from diagenesis only in temperature and pressure.
Diagenesis occurs at _________ temperature and pressure.
A. very high
B. high
C. intermediate
D. low
E. all of the above
2.
Regional metamorphism of the granulite-amphibolite facies occurs deep in the
crust at ________ margins.
A. convergent
B. divergent
C. translational
D. intracontinental
E. none of the above
3.
When a rock melts, it is no longer a rock, it becomes a magma, and when it
cools, an igneous rock. The melting point of rock is partially controlled by
the amount of water in the rock, which is why upper mantle rocks melt so
easily near __________________.
A. translational faults
B. mid-ocean ridges
C. subduction zones
D. arctic islands
E. all of the above
4.
Differential stress has a direction of maximum stress which tends to flatten
minerals such as __________ on planes of foliation.
A. quartz
B. feldspar
C. mica
D. calcite
E. none of the above
5.
Slaty cleavage is along planes perpendicular to:
A. the original bedding
B. the normal to the original bedding
C. the maximum stress direction
D. the minimum stress direction
E. both A and C
6.
Quartz and _______________ form the light colored bands in gneiss.
A. biotite
B. amphiboles
C. pyroxenes
D. feldspar
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E.
7.
8.
all of the above
When limestone is metamorphosed into marble, no foliation occurs but the
__________ crystals increase in size.
A. quartz
B. biotite
C. calcite
D. amphibole
E. pyroxene
Dynamic metamorphism is also called ____________ metamorphism.
A. catatonic
B. cataclastic
C. catastrophic
D. calamatic
E. catablastic
9.
Contact metamorphism occurs adjacent to igneous intrusions, commonly
resulting in a metamorphic _______.
A. aureole
B. oreo
C. extrusion
D. subduction
E. pediment
10.
Which principle of stratigraphy states that any horizontal sedimentary bed
is younger than the bed below it but older than the bed above it?
A. principle of chronological sequences
B. principle of cross-cutting relationships
C. principle of original horizontality
D. principle of stratigraphic superposition
E. principle of biostratigraphy
11.
If a tilted sedimentary bed is cut by a vertical intrusive dike (i.e., the
dike is not tilted in any way), the sequence of events in this case must have
been:
A. the dike intruded, then the bed formed around it, then the bed got
tilted by tectonic stresses
B. the bed got intruded, then the dike got deposited, then the bed
got tilted by tectonic stresses
C. the region got tilted by tectonic stresses, then the bed got
deposited, then the dike intruded
D. the bed got deposited, then the dike intruded, then the region got
tilted by tectonic stresses
E. the bed got deposited, then the region got tilted by tectonic
stresses, then the dike intruded
12.
Which of the following is NOT a type of unconformity?
A. bedding plane
B. disconformity
C. angular unconformity
D. nonconformity
E. all of the above are unconformities
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13. The correct arrangement of the different types of geologic time divisions,
from longest to shortest, is:
A. epochs, periods, eras, eons
B. periods, eons, epochs, eras
C. eons, eras, periods, epochs
D. eons, epochs, eras, periods
E. eras, periods, epochs, eons
14. Which of the following lists shows the youngest time division in each of
the four categories mentioned in question 13?
A. Hadean, Paleozoic, Cambrian, Paleocene
B. Phanerozoic, Cenozoic, Quaternary, Holocene
C. Phanerozoic, Mesozoic, Tertiary, Holocene
D. Hadean, Cenozoic, Jurassic, Pleistocene
E. Precambrian, Paleozoic, Cambrian, Paleocene
15.
Which of the following statements is true of beta decay:
A. an atom releases a pair of protons and a pair of neutrons from
the nucleus
B. an atom releases a proton and a neutron from the nucleus
C. an atom releases an electron from the nucleus causing a neutron to
turn into a proton
D. an atom absorbs an electron into the nucleus causing the atomic
number to decrease by 1
E. an atom remains unchanged but gives off gamma rays and generates
a lot of heat
16.
Radioactive decay causes U-238 to ultimately break down into Pb-206. In
this reaction:
A. U-238 is a parent isotope and Pb-206 is a daughter isotope
B. U-238 is a daughter isotope and Pb-206 is a parent isotope
C. U-238 and Pb-206 are both daughter isotopes
D. U-238 and Pb-206 are both parent isotopes
E. U-238 is a parent isotope and Pb-206 is a second cousin, twice
removed
17.
If the half-life of a radioactive isotope is 1 million years and a crystal
forms containing 100 of these isotopes, how old is the crystal at the point
in time when only 25 of the original radioactive isotopes are left in the
crystal?
A. 1 million years old
B. 2 million years old
C. 3 million years old
D. 4 million years old
E. 5 million years old
18. How old have moon rocks been determined to be, based on radiometric dating?
A. 6 billion years old
B. 4.5 billion years old
C. 4 billion years old
D. 3 billion years old
E. 2.5 billion years old
19.
It is safer to walk on thin ice with snow-shoes rather than with pointed
high heels because:
A. high heels impart a greater force on the ice
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B.
C.
D.
E.
20.
21.
22.
23.
snow-shoes
snow-shoes
high heels
snow-shoes
impart
impart
impart
impart
a smaller force on the ice
a smaller stress on the ice
a smaller strain on the ice
an isotropic pressure on the ice
If a rock deforms under the influence of a stress, but then returns to its
original shape when the stress is removed, then the deformation behavior is
described as:
A. brittle
B. plastic
C. elastic
D. ductile
E. magical
For rocks that
increases:
A. the
B. the
C. the
D. the
E. the
are being deformed inside the crust, as the temperature
rocks get more brittle
rocks get more ductile
rocks get more elastic
strain rate increases
pressure must start to decrease
Which of the following statements about joints is true?
A. joints form as two sides of a fracture slide past each other
B. joints typically open by several meters
C. joints only form due to the cooling of lava or magma
D. joints always form perpendicular to the direction of tensional
stress
E. joints are responsible for many earthquakes
The type of fault that forms in a region of the crust undergoing a
combination of extension and lateral sliding:
A. reverse fault
B. normal fault
C. oblique-slip fault
D. left-lateral fault
E. right-lateral fault
24.
Along any inclined fault:
A. the footwall moves up and the hanging wall moves down
B. the hanging wall moves up and the footwall moves down
C. the footwall moves to the left and the hanging wall moves to the
right
D. the footwall moves to the right and the hanging wall moves to
the left
E. the footwall is underneath the fault plane and the hanging wall
is above it
25.
If a fault
A.
B.
C.
D.
E.
has a dip of 90°, then it is:
horizontal
vertical
a normal fault
a reverse fault
a strike-slip fault
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26.
Which of the following is an example of a M7.3 normal fault related
earthquake that happened in 1983?
A. the great San Francisco earthquake
B. the Good Friday earthquake in Alaska
C. the Charleston, South Carolina earthquake
D. the Borah Peak, Idaho earthquake
E. the New Madrid earthquake
27.
Along the San Andreas fault, the west side is moving towards the north and
the east side is moving relatively towards the south. This makes the San
Andreas fault:
A. a normal fault
B. a right-lateral fault
C. a left-lateral fault
D. a reverse fault
E. either a left or right-lateral fault (depending on what side of
the fault you are standing on)
28.
What type of fold creates zig-zag patterns where the folded rocks are
exposed at the surface?
A. anticlines
B. synclines
C. monoclines
D. any plunging fold
E. all folds, regardless of type or orientation
29.
On 26th December 2004, a magnitude 9.1 earthquake caused a tsunami that
killed about 283,000 people around the rim of the Indian Ocean. The
earthquake itself occurred off the coast of this country:
A. India
B. Thailand
C. Sri Lanka
D. Indonesia
E. Sumatra
30.
A magnitude 9.0 earthquake hit the continental United States in the year
1700, also producing a tsunami. Where did this earthquake occur?
A. along the San Andreas fault of California
B. southern Alaska
C. in the New Madrid region of Missouri
D. near Hilo, Hawaii
E. in the Pacific Northwest
31.
32.
Where do 80% of all earthquakes on Earth occur?
A. along the tectonic plate boundaries
B. in the continental interiors
C. around the circum-Pacific belt
D. the mid-Atlantic ridge
E. Alaska
The largest earthquake in historic times had a magnitude of 9.5 and
occurred off the coast of:
A. Oregon
B. Chile
C. Mexico
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D.
E.
33.
34.
Alaska
Indonesia
What type of instrument creates the picture to the right?
A. an accelerometer
B. a seismogram
C. a seismograph
D. a magnetometer
E. a cardiograph
In the picture on the right, what is
represented by the quantity labeled as
“A”?
A. the S-wave amplitude
B. the P-wave amplitude
C. the earthquake magnitude
D. the seismic wave speed
E. the P-S time interval
35.
What is the typical depth of the epicenter of an earthquake?
A. a few km
B. up to 700 km
C. the same depth as the focus
D. zero (at the surface)
E. any depth is possible
36.
Which of the following types of waves is unable to pass through any liquid?
A. P-waves
B. sound waves
C. water waves
D. primary waves
E. S-waves
37.
The Modified Mercalli scale is used to measure:
A. the Richter magnitude of an earthquake
B. the moment magnitude of an earthquake
C. the intensity of an earthquake
D. the amount of energy released during an earthquake
E. the height of the surface waves during an earthquake
38.
Which of the following is an accurate definition of the term tsunami?
A. it is a type of earthquake that occurs under the ocean
B. it is a type of seismic wave that causes a lot of damage to tall
buildings
C. it is a water wave generated in the ocean as a result of an
earthquake
D. it is a type of landslide triggered in a mountainous region
during an earthquake
E. it is an ancient Japanese method of studying earthquakes
39.
When seismic waves from an earthquake reach the boundary between the mantle
and the liquid outer core:
A. all of the body waves get refracted
B. all of the body waves get reflected, but none are refracted
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C. all P-waves stop because they are unable to move through the
outer core
D. all S-waves vanish because they cannot move through a liquid
E. all P-waves speed up as they pass into the outer core
40.
As a result of seismic waves interacting with the liquid layer mentioned in
the previous question, within what region do seismographs show no record of
the earthquake ever having occurred?
A. the S-wave shadow zone
B. the P-wave shadow zone
C. the epicenter
D. the opposite side of the earth to the earthquake
E. no such region exists
41.
The boundary between the crust and the mantle is called the:
A. Mojo
B. Jomo
C. Ohno
D. Moho
E. SloMo
42.
The Earth has a magnetic field because:
A. magnetic minerals are common at temperatures above the Curie
point
B. it has a magnetic iron-nickel core
C. the liquid outer core creates an electric current which induces
a magnetic field
D. all planets have magnetic fields when they form
E. it forms a magnetic resonance with planet Mercury
43.
What occurs at
A. the
B. the
C. the
D. the
E. the
44.
Which of the following portions of the ocean floor is the flattest?
A. ocean trenches
B. mid-ocean ridges
C. continental slope
D. abyssal plains
E. continental rise
45.
a consistent water depth of about 135 m?
true edges of the continents
edge of the continental shelf
start of the continental rise
start of an ocean trench
limit of penetration by sunlight
The correct order of the 4 layers of rock types that make up oceanic crust,
from top to bottom is:
A. pillow basalts – sediments – gabbro – sheeted dike complex
B. pillow basalts – sheeted dike complex – gabbro – sediments
C. sediments – pillow basalts – sheeted dike complex – gabbro
D. sediments – pillow basalts – gabbro – sheeted dike complex
E. sheeted dike complex – gabbro – pillow basalts – sediments
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46. An example of a young, active mountain range that forms a part of the
American Cordillera is:
A. the Alps
B. the Andes
C. the Himalayas
D. the Appalachians
E. the Caledonides
47.
48.
The pile of sediments scraped off the top of an ocean plate where it begins
to subduct is called:
A. a trench
B. a forearc
C. an accretionary wedge
D. a backarc
E. a pluton
In which of these places would you expect to find a suture zone?
A. Himalayas
B. Sierra Nevada
C. East African Rift Valley
D. mid-ocean ridge
E. Cascades
49.
The Appalachians formed after the breakup and subsequent reassembling of
the ancient supercontinent:
A. Gondwana
B. Pangea
C. Rodinia
D. Madagascar
E. Nubia
50.
When a microcontinent collides with a larger continent, it gets added to
the edge of the continent and is then referred to as a/an:
A. accreted continent
B. terrane
C. island arc
D. accretionary wedge
E. macrocontinent
BONUS QUESTIONS
51.
The end of the age of dinosaurs 66 million years ago also heralded the
start of the:
A. Cambrian
B. Holocene
C. Pliocene
D. Hadean
E. Tertiary
52. Cambrian, Ordovician, Silurian, Devonian, Carboniferous (Camels Only Sit
Down Carefully). What comes next?
A. Triassic
B. Tertiary
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C.
D.
E.
53.
54.
55.
Quaternary
Permian
Jurassic
The Great San Francisco earthquake in 1906 was the most devastating
earthquake in the history of the United States, killing about 3,000 people.
This magnitude 7.8 earthquake happened because of motion along the:
A. Cascadia subduction zone
B. Aleutians subduction zone
C. San Andreas fault
D. Borah Peak fault
E. Basin and Range faults
Which of the following statements is TRUE?
A. an earthquake has only one magnitude but the intensity can vary
B. an earthquake has only one intensity but the magnitude can vary
C. the magnitude of an earthquake decreases with increasing
distance from the epicenter
D. the intensity of an earthquake is the least at the epicenter
E. earthquake intensity is measured using the Richter scale
The tectonic plate that used to exist off the west coast of North America
but which has long since been subducted, was the:
A. Juan da Fuca plate
B. Farallon plate
C. Cocos plate
D. Pacific plate
E. Nazca plate
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