Download - Catalyst

ESS 101 Midterm Winter 2012
Name
Student #:
VERSION A
Provide the best answer for the following multiple-choice questions. There are 41 regular test questions
(including 3 laboratory questions) and 4 bonus questions. The bonus questions can only help your score. Circle
the correct answer on your test paper and hand the test in with your scantron form.
1.
a.
b.
c.
d.
e.
As igneous rock partially melts the magma is typically __________.
more mafic (Fe-rich) than the rock
more felsic (silica-rich) than the rock
lower density than the rock
answers a and c are both correct
answers b and c are both correct
2. The silicate mineral amphibole has 50% of its silicate tetrahedra possessing 3-shared oxygen atoms and
1-unshared and 50% of its silicate tetrahedra possessing 2-shared oxygen atoms and 2-unshared oxygen
atoms. What is the ratio of Si:O in the tetrahedral structure of this mineral?
a. 1:4
b. 1:3
c. 1:2.75
d. 1:2.5
e. 1:2
3-5
3.
4.
5.
Match the magma/lava type with the appropriate geographic/tectonic setting where it likely formed.
Columbia Plateau
a. basalt
Asthenosphere
b. granite
Mount Fuji, Japan
c. andesite
d. peridotite
e. rhyolite
6.
a.
b.
c.
d.
e.
What kind of tectonic setting is represented by the Ural Mountains, which separate Asia from Europe?
ancient divergent margin
ancient convergent margin (ocean-continental subduction)
ancient convergent margin (ocean-ocean subduction)
ancient hotspot
ancient collision margin (continent-continent)
7. Following differentiation the Earth became compositionally zoned according to ________.
a.
valency state of constituent atoms
b.
total volume of constituent matter
c.
density of constituent matter
d.
magnetic properties of constituent matter
e.
none of the above answers are correct as the earth is not compositionally differentiated
8. The cause of volcanism observed in the Andes Mountains (South America) is most similar to that of _____.
a.
Yellowstone Park
b.
Japan
c.
the Columbia Plateau
d.
Himalaya Mountains
e.
the Hawaiian Islands
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9. What scientific observations of the solar system indicate that the sun and planets formed from a rotating,
disk-shaped, nebular dust cloud?
a. The planets all revolve in a counter-clockwise direction around the sun
b. Most of the planets and their moons rotate on their axis in a counter-clockwise direction
c. The planetary orbits are aligned along the sun’s equatorial plane.
d. all of the above answers are correct
e. only answers a an b are correct
10. What mineral group is a major economic source of lead?
a.
sulfide
b.
halide
c.
oxide
d.
carbonate
e.
silicate
11. The __________ mineral group is a major economic source lime for cement.
a. sulfide
b. halide
c. oxide
d. carbonate
e. silicate
12. Meteorites that strike the earth are predominantly composed of ____________?
a. iron-nickel and silicate minerals
b. hydrogen sulfide and silicate minerals
c. carbon-based materials and iron-nickel
d. only material found in the earth’s core
e. mainly materials found only in continental crust
13. Why are P-waves completely absorbed as they enter the outer core?
a. the outer core is composed of low density liquid iron
b. the outer core is at the pressure melting temperature for iron-nickel
c. P-waves actually accelerate in the outer core
d. the outer core represents a part of the earth’s interior that has a unique composition
e. none of the above answers are correct as P-waves are not completely absorbed in the outer core.
14. During differentiation of the earth, heat was generated from _________.
a. kinetic energy of impacting planetesimals
b. compressional heating during condensation of planetesimals
c. radioactive heating
d. all of the above are correct
e. only answers a and b are correct
15. Why does the Yellowstone hotspot volcanism produce more explosive volcanic eruptions than the
Hawaiian hotspot volcanism?
a. the Yellowstone hotspot is situated over an old subduction zone
b. Yellowstone hotspot magma contacts groundwater, while the Hawiian hotspot magma does not
c. upwelling basaltic magma partially melts the overlying continental crust producing viscous rhyolitic lava
d. all of the above answers are correct
e. none of the above answers are correct, as both hotspots produce exclusively basaltic magma
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16. What type of seismic wave shadow zone is shown on the image above?
a.
P-wave
b.
S-wave
c.
surface wave
d.
P and S-wave
e.
all of the above answers are correct
17. How can one best explain the seismic wave properties shown in the above diagram.
a.
refraction of seismic waves due to density changes
b.
absorption of seismic waves due to phase change from solid to liquid
c.
refraction of seismic waves due to wave amplitude
d.
all of the above answers are correct
e.
only answers a and b are correct
18. Which of the following bond strength rankings are in the correct order from weakest to strongest?
a. metallic, Van der Waals, covalent, ionic
b. metallic, ionic, covalent, Van der Waal
c. ionic, Van der Waal, metallic, covalent
d. ionic, covalent, Van der Waal, metallic
e. Van der Waal, metallic, ionic, covalent
19. How can we best explain the fact that the inner and outer cores are both composed of metallic iron (Fe) and
nickel (Ni) yet the outer core is liquid and the inner core solid?
a. the outer core is solid and the inner core is solid
b. the melting temperature for Fe-Ni is greater than the geothermal gradient temperature in the outer core
c. the melting temperature for Fe-Ni is the same as the geothermal gradient emperature in the outer core.
d. the melting temperature for Fe-Ni is lower than the geothermal gradient temperature in the outer core.
e. the actual temperature of the outer core is greater than the inner core's actual temperature.
20.
a.
b.
c.
d.
e.
Which of the following answers is not a characteristic of a metal?
all metals are anions (negatively charged ions)
metallically bonded minerals are excellent conductors of heat and electricity
metals are ductile and malleable
metals have high thermal and electrical conductivity
all metals are cations (positively charged ions)
21. Which volcanic gas was not added to the earth’s atmosphere during early differentiation of the planet?
a. CO2
b. O2
c. H2O (vapor)
d. N2
e. H2
4
22. The lava composition of Mt. St. Helens is __________ and it tends to be more __________ than lavas
erupted from Mt. Rainier.
a.
andesite, silica-rich
b.
basalt, viscous
c.
andesite, iron-rich
d.
dacite, iron-rich
e.
dacite, silica-rich
23.
a.
b.
c.
d.
e.
The Olympic and Coast Mountains are composed of _____:
marine sedimentary rock scraped off from the ocean floor during subduction
gabbro formed from upwelling asthenospheric melt
peridotite (>90% olivine) crystallized directly from the mantle
granite crystallized from a continental collision
andesite formed from a partial melt of the basaltic oceanic crust
24. Which of the following plate motions would not likely occur in the future?
a. The Mediterranean Sea will close as the African Plate converges with the Eurasian Plate
b. western California will be displaced northward towards Alaska along a transform fault
c. The Isthmus of Panama will close and the Gulf Stream current will be diverted northward to Europe
d. East Africa will rift apart from the main portion of the African continent
e. The Juan de Fuca spreading ridge will be subducted and Cascade volcanism will cease
25. The rock shown in the image below has a _______________ texture.
a. phaneritic (coarse-grained)
b. aphanitic (fine-grained)
c. porphyritic (two stages of cooling
d. porous
e. glassy
26. Which mineral crystallized first?
a. small black mineral included within the white mineral
b. large white mineral
c. grey matrix minerals
d. cannot be determined by this image
e. none of the above answers are correct as the minerals all formed at the same time.
Structure of subduction zone. Questions 27-28
27.
28.
Match the structure within the subduction zone with the appropriate geographic feature in Washington State
Use the answers below to answer questions 27-28 (numbers shown on the above diagram).
a. Olympic Mountains
b. Puget Lowland
c. Cascade Mountains
d. Columbia Plateau
e. Rocky Mountains
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29. Divergent margins typically originate under continents because __________.
a.
the upper mantle is hotter under continental lithosphere than ocean lithosphere
b.
the insulating property of thick continental lithosphere retains more heat than ocean lithosphere
c.
the upper mantle is thicker under continental lithosphere
d.
the upper mantle is squeezed to the surface where continents collide
e.
none of the above answers are correct, as divergent margins only originate under ocean crust
30. Magnetic minerals that crystallize in a lava flow erupted near the South Pole today will ________.
a. be oriented perpendicular to the surface of the lava flow
b. be oriented parallel to the surface of the lava flow
c. will have a normal polarity and point toward magnetic north
d. answer a and c are correct
e. answers b and c are correct
31-33. Use the rock-composition diagram shown below to answer questions 31-33.
31. A aphanitic (volcanic) rock composed of 10% plagioclase, 5% pyroxene, and 85% olivine would be
classified as ________.
a. basalt
b. diorite
c. komatitite
d. peridotite
e. granite
32. According to the above classification diagram diorite may contain between ________ potassium feldspar.
a. 0%
b. 0-5%
c. 5-10%
d. 10-20%
e. >20%
33. According to the above diagram, which of the following minerals would not be found in the same rock?
a. amphibole and pyroxene
b. biotite and olivine
c. amphibole and quartz
d. quartz and pyroxene
e. olivine and Ca-rich plagioclase
34. What evidence have geophysicists used to indicate that the core is metallic and has a liquid component?
a. seismic wave studies, specifically the S-wave shadow zone
b. the presence of the earth’s magnetic field
c. a segment of the metallic core has been brought to the surface along deep kimberlite dikes
d. all of the above answers are correct
e. only answers a and b are correct
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35. How are minerals produced on earth?
a. minerals can crystallize directly from a magmatic melt
b. minerals can be produced artificially in high-pressure chambers
c. minerals can precipitate from aqueous solutions
d. all of the above answers are correct
e. only answers a and c are correct
36. What are the mechanisms that likely drive subduction of the ocean lithosphere?
a. ridge push
b. plate sliding
c. slab pull
d. all of the above answers are correct
e. only answers a and c are correct
37. Why does Ca-rich plagioclase develop cleavage planes yet it is a framework silicate mineral with all its
oxygen atoms shared between tetrahedra?
a.
this mineral does not cleave.
b.
this mineral may have an Al atom in its tetrahedra which requires additional ionic bonds with Ca atoms
c.
this mineral is not a silicate mineral and consists of weak ionic bond between
d.
the mineral cleaves between covalent bonds separating sheet pairs
e.
none of the above are correct
38. Australia has unique faunal (animal) assemblages compared to the other continents because _______.
a.
its plate moved faster than other tectonic plates causing divergent evolution.
b.
it was the center of a bolide imact that cause a mass extinction during the Triassic Period
c.
it has been tectonically isolated from other continents for a very long period of time
d.
it was below sea level up until the past 3.5 million years
e.
none of the above answers are correct
Lab Questions
39. In the geologic techniques lab you calculated the stream length of a section of the Wenatchee River _____.
a. Using a string and the topographic map’s bar scale
b. Using a planimeter
c. Using the measurement noted directly on the topographic map
d. Using a string and the topographic map’s representative fraction
e. None of the above answers are correct. We did not measure a section of the Wenatchee R.’s stream length
40. In the plate tectonics lab we observed that oceanic crust comprising the Juan de Fuca plate was being
created at the spreading ridge at a rate __________ the rate of its subduction beneath the North American plate.
a.
the same as
b.
less than
c.
more than
d.
not known compared to
e.
that is accelerating compared to
41. In the minerals lab the main diagnostic criteria for identifying biotite mica was _______.
a.
its cleavage into dark flexible sheets
b.
its cleavage into light flexible sheets
c.
its glassy appearance
d.
its reaction with hydrochloric acid
e.
its cubic cleavage
Bonus Questions (There are four bonus questions #42-45) Next Page
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42. Which vest is Terry’s favorite color to wear?
a. His orange vest
b. His light tan canvas vest
c. His red vest
d. His UW vest.
e. None of the above answers are correct, as Terry likes all of his vests the same.
43. What is Terry’s favorite tree?
a. gingko biloba
b. live oak
c. bristlecone pine
d. Colorado blue spruce
e. Douglas fir
44. What was significant about Friday, February 3rd?
a. Terry proclaimed it the first day of spring
b. It was a day that Terry wore his favorite yellow vest
c. It was the day after Terry got his winter haircut
d. It was the 40th anniversary of the inception of Plate Tectonic theory
e. It was the day that Emmanual Kant proposed the nebular hypothesis 500 years ago
45. Why did Terry miss lecture the first week of the quarter?
a. He was attending the Northwest Geological society meeting in Seattle.
b. He had a curriculum meeting with undergraduate Dean’s office
c. He had an emergency root canal procedure at his dentist’s office
d. His ferry was down due to a problem with the loading dock
e. None of the above answers are correct, as Terry has not missed a lecture during the first half of the quarter