Geol 101: Physical Geology
Summer 2007
EXAM 1
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 7 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.
2.
Who is considered to be the “father of modern geology?”
A. Plato
B. Pliny the Elder
C. James Ussher
D. James Hutton
E. Alfred Wegener
Most modern geologic study is based on the precept of the Principle of
Uniformitarianism, which states:
A. the present is the key to the past
B. the past is the key to the future
C. the past repeats itself
D. the past’s future is the same as the future’s past
E. nothing ever changes in geology
3.
In glass, atoms are arranged in a:
(A) regular framework
(B) random orientation
4.
A silicate mineral contains:
(A) oxygen
(B) sulfur
5.
Mica sheets are held together by:
(A) Van der Waal's bonds
(B) ionic bonds
6.
Manufactured diamonds are:
(A) not minerals
(B) minerals
7.
8.
Diamonds are
diamond stone
(A)
(B)
(C)
(D)
(E)
2-3 billion years old. This is known because what part of a
can be dated radiometrically?
the polish
the carbon atoms
the inclusions
all of the above
none of the above
Strictly speaking, amber is a/an:
(A) mineral
(B) organic material
(C) both of these
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9.
10.
11.
A mineral that breaks into sheets has cleavage in how many directions?
(A) none
(B) one
(C) two
(D) three
(E) four
Which of the following statements is FALSE regarding evidence to suggest
that Africa and South America were once joined?
A. the two continents fit together well along their true edges at
an ocean depth of 900 m
B. both continents contain fossils of the plant Glossopteris and
the aquatic reptile Mesosaurus
C. rocks that are about 550 million years old match up perfectly
across the continents
D. both continents show compatible evidence of a glacial period
during the Carboniferous
E. the Caledonides mountain range matches up across the two
continents
Which of the following was NOT part of Gondwana?
A. Eurasia
B. Africa
C. India
D. Australia
E. Antarctica
12.
Paleomagnetism studies often consider the latitude at which a certain rock
formed. Which of the following magnetic properties only changes as a function
of latitude?
A. magnetic polarity
B. magnetic reversals
C. magnetic inclination
13.
In the modern age, compass needles point towards magnetic north. However,
about 700,000 years ago, compass needles would have pointed south because it
was during a period of:
A. normal polarity
B. positive polarity
C. inverse polarity
D. reverse polarity
E. shoddy compass construction
14.
Which of these statements about paleomagnetism as determined from a study
of spreading ridges is FALSE?
A. there is a clear paleomagnetic signal in rocks to either side of a
spreading ridge
B. rocks along spreading ridges all show normal polarity, no matter what
their age
C. the paleomagnetic pattern on one side of a ridge is a mirror image of
that on the other side of the ridge
D. there is evidence that Earth’s magnetic poles reverse approximately
every half-million years
E. all the world’s spreading ridges show evidence of paleomagnetic
reversals in the adjacent ocean rocks
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15.
If you were to collect samples of basalt at the following locations on the
sea floor of the North Atlantic ocean, which sample would be the oldest?
A. along the spreading ridge
B. where the spreading ridge is exposed above water in Iceland
C. just east of the spreading ridge
D. just west of the spreading ridge
E. along the coast of Africa
16.
The oldest ocean crust anywhere in the Earth’s oceans is about
____________ years old.
A. 4000
B. 12 million
C. 180 million
D. 250 million
E. 4.6 billion
17.
A rift valley can be found in the following type of plate tectonic setting:
A. divergent
B. convergent (ocean-ocean type)
C. convergent (ocean-continent type)
D. convergent (continent-continent type)
E. transform
18.
The Cascades mountain range in the western U.S.A. is found in the following
type of plate tectonic setting:
A. divergent
B. convergent (ocean-ocean type)
C. convergent (ocean-continent type)
D. convergent (continent-continent type)
E. transform
19.
The San Andreas fault is found in the following type of plate tectonic
setting:
A. divergent
B. convergent (ocean-ocean type)
C. convergent (ocean-continent type)
D. convergent (continent-continent type)
E. transform
20.
21.
An island arc can be found in the following type of plate tectonic setting:
A. divergent
B. convergent (ocean-ocean type)
C. convergent (ocean-continent type)
D. convergent (continent-continent type)
E. transform
The Himalayas mountains are found in the following type of plate tectonic
setting:
A. divergent
B. convergent (ocean-ocean type)
C. convergent (ocean-continent type)
D. convergent (continent-continent type)
E. transform
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22.
When a mantle plume rises from the outer core boundary to the Earth’s
surface, it results in a/an:
A. hot spot
B. island arc
C. volcanic arc
D. subduction zone
E. suture zone
23.
On average, the geothermal gradient inside the Earth is about:
A. 1000°C per kilometer
B. 100°C per kilometer
C. 50°C per kilometer
D. 25°C per kilometer
E. 10°C per kilometer
24.
The inside of the earth is not completely molten (i.e. liquid) because:
A. it never gets hot enough to melt rocks deep in the earth
B. the melting temperature of rocks increases as pressure increases
C. the earth would collapse in on itself if it had a liquid
interior
D. none of the above because the inside of the earth is completely
molten
25.
As a rock starts to melt, the minerals with the lowest melting temperature
will start to melt first, forming magma. This melted portion can get
squeezed away from the remaining solid rock through a process called:
A. partial melting
B. fractionation
C. differentiation
D. buoyancy
E. crystallization
26.
Newly formed magma starts to rise towards the Earth’s surface because:
A. it is sucked upwards by erupting volcanoes
B. it is squeezed upwards by the force of tectonic plate collisions
C. it is less dense than the rocks around it
D. there is no gravity inside the earth
27.
The type of magma that has the lowest silica content is:
A. intermediate
B. ultramafic
C. mafic
D. felsic
E. all magma has the same silica content
28.
The type of lava that flows the fastest has:
A. a high temperature and a high silica content
B. a high temperature and a low silica content
C. a relatively low temperature and a high silica content
D. a relatively low temperature and a low silica content
4
E. all lava flows at the same speed, regardless of temperature or
silica content
29.
Which of the following terms has the same meaning as coarse-grained texture
in igneous rocks?
A. aphanitic
B. phaneritic
C. porphyritic
D. pyroclastic
E. pegmatitic
30.
What type of rock typically shows a vesicular texture?
A. basalt
B. tuff
C. pumice
31.
Which of the following minerals is NOT found in Bowen’s Reaction Series?
A. plagioclase
B. amphibole
C. olivine
D. calcite
E. quartz
32.
How many active volcanoes are there in the world?
A. about a million
B. around 10,000
C. around 1,500
D. around 800
E. 42
33.
The type of volcanic hazard that involves a huge cloud of tephra rushing
down the slopes of a volcano is a:
A. lahar
B. lava bomb
C. pyroclastic flow
D. gas cloud
E. ash fall
34.
The type of volcanic hazard that involves a mudflow made of volcanic ash is
a:
A. lahar
B. lava bomb
C. pyroclastic flow
D. gas cloud
E. ash fall
35.
Which of the following is characteristic of nonexplosive eruptions?
A. shield volcanoes
B. high-viscosity lava
C. felsic lava
D. Plinian columns
E. island arc volcanoes like Krakatau
36.
What type of volcano is Mount St. Helens?
A. stratovolcano
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B.
C.
D.
E.
37.
38.
shield volcano
cinder cone
lava dome
tuff ring
The most active volcano in the Cascades is (1) __________ but the largest
known eruption that occurred about 6800 years ago was the eruption of (2)
__________.
A. (1) Crater Lake
(2) Mt. St. Helens
B. (1) Mt. St. Helens (2) Lassen Peak
C. (1) Mt. St. Helens
(2) Mt. Mazama
D. (1) Mt. Mazama
(2) Mt. Tehama
E. (1) Mt. Shasta
(2) Mt. St. Helens
Which of the following sequence of events accurately describes the build-up
to the eruption of Mount St. Helens exactly 27 years ago today, on May 18th,
1980?
A. steam and ash release – bulge on mountain – earthquake –
landslide – lateral blast
B. bulge on mountain – steam and ash release – earthquake –
landslide – lateral blast
C. bulge on mountain – earthquake – steam and ash release –
landslide – lateral blast
D. steam and ash release – bulge on mountain – landslide – lateral
blast – earthquake
E. bulge on mountain – earthquake – steam and ash release – lateral
blast – landslide
39.
Diagenesis can occur by:
(A) recrystallization
(B) frost wedging
40.
Clastic sedimentary rock is formed out of:
(A) chemical reactions
(B) detritus
41.
Sediment can be converted to sedimentary rock by:
(A) diagenesis
(B) metamorphism
42. The spires at Bryce Canyon National Monument are the result of:
(A) differential weathering
(B) volcanic extrusion
43.
Lake sediments such as varves suggest a:
(A) low energy depositional environment
(B) high energy depositional environment
44.
The removal of material from its source area is:
(A) weathering
(B) erosion
45.
Technically, lunar soil is not "soil"; it is:
(A) regolith
(B) mineral
6
(C) humus
46.
47.
Because they occur in a reducing environment, organic sediments such as
coal are often associated with the iron sulfide mineral:
(A) pyrite
(B) hematite
(C) limonite
(D) magnetite
(E) all of the above
Rock salt and gypsum are good examples of:
(A) evaporites
(B) clastics
48. The process by which slabs of rocks bounded by sheet joints slip off host
rock is:
(A) foliation
(B) exfoliation
49.
Yosemite National Park is famous for its domes, which were formed by:
(A) exfoliation
(B) volcanic action
(C) ocean bottom processes
50.
The opening of cracks by repeated freezing and thawing of water is:
(A) mechanical weathering
(B) chemical weathering
BONUS QUESTIONS
51.
What must always exist inside the crystal structure of a ferromagnesian
silicate mineral?
A. Ca and Na
B. Si and Ca
C. Fe and Mg
D. Fe and K
E. Mg and Na
52.
The top of Mt. Everest exhibits (1) __________ which indicates that (2)
___________.
A. (1) a suture zone
(2) it must be an ocean-continent
plate boundary
B. (1) a crater
(2) it must be a volcano
C. (1) constant elevation (2) the collision between India and Asia is
now complete
D. (1) glacial features
(2) it used to be near the south pole
as part of Gondwana
E. (1) sea shell fossils
(2) it is made of old ocean floor that
got uplifted during collision
53.
The largest type of pluton is called a:
A. dike
B. volcanic pipe
C. laccolith
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D.
E.
sill
batholith
54.
The world’s largest lava dome is:
A. Mount St. Helens
B. Mauna Loa
C. Mount Hood
D. Lassen Peak
E. Crater Lake
55.
The
last Cascades volcano to erupt before Mount St. Helens in 1980 was:
A. also Mount St. Helens
B. Mount Rainier
C. Mount Hood
D. Lassen Peak
E. Mount Shasta
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