Download Midterm 1, Winter 2012 with answers

University of Guelph
Winter 2012 Semester
Midterm 1
Principles of Geology (GEOL*1100DE)
Instructor: Steven Sadura
50 Multiple choice questions, Open book.
Due: Friday, February 10, 2012 at 12:00 midnight
1. Match one of the following terms with this statement. An explosion that scattered clouds of
matter into space and caused particles to become charged.
A. fission
B. 4. 6 billion years ago
C. thermal event
D. nebular hypothesis
E. black hole
F. Doppler Effect
G. fusion
*H. Big Bang
2. Theory that our solar system evolved from a large rotating cloud of charged particles and
elements.
A. fission reaction
B. 4. 6 million years ago
C. thermal conversion
*D. nebular hypothesis
E. black hole
F. Doppler Effect
G. cold fusion
H. 13.7 billion years ago
I. Big Bang
3. A place where the density of matter is so great not even light can escape and all particles are
uncharged.
A. fission gap
B. core of the Earth
C. nebular hypothesis
*D. black hole
E. Doppler Effect
F. fusion reactors
G. Big Bang
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4. Extreme heat is required for this type of reaction, where two hydrogen atoms combine to
form a helium atom.
A. fission
B. Big Bang
C. exothermic
D. nebular hypothesis
E. black hole
F. Doppler Effect
*G. fusion
5. The relatively young age (200 million years) of the oceanic crust and old age (up to 4 billion
years) of the continental crust supports the notion that:
*A. oceanic crust is continuously being recycled by the process of subduction and that
continental crust is almost never subducted
B. ocean basins are being filled by relatively young sediments
C. planetary differentiation occurred during the last 200 million years
D. all of the above
E. only A and B are correct
6. Which of the following statement(s) is (are) true of the Doppler Effect.
A. low frequency long light waves appear red
B. distant stars have more red coloration than nearby stars
C. distant reddish stars are moving away from us
*D. all of the above
E. none of the above
7. The Earth’s layers can be divided up in several ways. List the Earth’s internal layers,
defined by chemical composition, in correct order from the center outward.
A. outer core, inner mantle, crust
B. inner core, outer core, mesosphere, asthenosphere, lithosphere
*C. inner core, outer core, mantle, crust
D. core, crust, mantle, hydrosphere
8. Kelvin’s estimate of the Earth’s age (molten state) was out by 2 orders of magnitude (40
million, as opposed to 4. 5 billion years ago). Kelvin was correct in assuming that the Earth
was formed by molten material and then cooled to form a crust, so where did he make his
mistake?
A. he assumed that Earth had only its original heat reserve, which was being replenished by
radioactive decay
B. he assumed that Earth had only its original heat reserve, which was being replenished by
solar radiation
*C. he assumed that Earth had only its original heat reserve, which was being depleted
D. he assumed that Earth was heated by solar radiation and fission of subatomic particles
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9. Which of these statements relates directly to Einstein’s theory of relativity (E = mc2)?
A. elements cool down during radioactive decay
B. radioactive decay can only occur on stars
*C. the difference in mass between the parent and daughter atom influences the amount of
energy released during radioactive decay
D. the speed of sound influences the amount of energy released during radioactive decay
10. The newly-formed molten planet Earth cooled to form concentric shells of elements. Which
statements describe the organization of the elements within these shells?
A. heavier elements, such as iron and nickel sank to form the inner solid core and lighter
elements formed the outer liquid core
B. heavier elements formed the crust, which is why the ground is hard
C. lighter elements, such as hydrogen, helium, silicon and sodium remained in the less dense
outer liquid core
*D. heavier elements, such as iron and nickel sank under the force of gravity to form the inner
and outer cores
11. Geologists created the geologic time scale in the early 19th century using relative dating
techniques. Numeric values were not added until _____________ was understood.
A. Principle of Fossil Succession
B. time of ancient life
*C. radiometric dating
D. Law of Superposition
E. time of recent life
12. Approximately when did cyanobacteria, the earliest known organism, evolve on Earth?
A. 4 billion years ago
B. The Paleozoic era
*C. 3.5 billion years ago
D. 542 million years ago
E. 65.5 million years ago
13. Approximate duration of the Precambrian era.
*A. 4 billion years
B. The Paleozoic era
C. 3.5 billion years
D. 542 million years
E. 65.5 million years
14. Which of the following best describes the Paleozoic era.
A. time of fossil succession
*B. time of ancient life
C. time of recent life
D. 3. 5 billion years ago
E. time of the dinosaurs
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15. Seismology is a geophysical technique which measures the behaviour of energy waves
within the Earth. Which of the following statements is (are) true?
A. denser materials transmit energy waves faster
B. discontinuity between materials of different density is indicated by reflection or
refraction of energy waves
C. boundary between materials of different density is indicated by a change in wave speed
and direction
*D. all of the above
E. none of the above
16. How is seismic evidence used to interpret the Earth’s internal structure?
A. since P-waves cannot transmit through fluid, the depth to the outer core can be estimated
B. since S-waves cannot transmit through fluid, the depth to the inner core can be estimated
C. P-waves and S-waves speed up in a dense solid, so depth to inner core can be estimated
*D. since S-waves cannot transmit through fluid, the depth to the outer core can be estimated
E. none of the above
17. Which of the following is true about the Earth's crust?
A. geothermal temperature declines with depth in the crust
*B. oceanic crust is made of basalt and continental crust is formed of mostly granite
C. continental crust is made of basalt and oceanic crust is formed from carbonates
D. all of the above
E. none of the above
18. Internal heat is transferred to the Earth’s surface most quickly by:
*A. convection
B. conduction
C. radiation
D. all of the above
E. A and C, but not B
19. Match one of the terms with the following phrase. All continents were once joined.
A. Gondwana
B. Eurasia
C. Precambrian
D. United Plates of America
*E. Pangea
F. all of the above are correct answers
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20. Match one of the terms with the following phrase. Places on the Earth’s surface where
convective plumes emerge from deep within the mantle.
A. hot spots
B. Eurasia
C. Hawaii
D. Mid- Atlantic Ridge
E. all of the above are correct
*F. A, C and D are all correct
21. Match one of the terms with the following phrase. New basaltic rocks are continually
formed by this process.
A. crystallization in a pluton
B. magnetic reversal
C. subduction
*D. ocean floor spreading
E. deposition by "glowing clouds"
22. Match one of the terms with the following phrase. Basalt responds to Earth’s magnetic field
because it contains this.
*A. iron-rich minerals
B. magnesium
C. plagioclase
D. volcanic glass fragments
E. All of the above are true
23. Although Wegener suggested Continental Drift in 1915, the scientific community did not
accept Plate Tectonic Theory until approximately when?
A. Darwin’s "On the Origin of Species" was published
*B. the music of the Beatles swept the nation
C. Banting discovered insulin
D. the launching of Sputnik
E. none of the above
24. Which statement correctly summarizes the Rock Cycle?
A. molten rock cools, metamorphic rocks are formed, igneous rocks are buried and weathered,
new minerals form, sedimentary rocks are formed.
B. molten rock cools, sedimentary rocks are uplifted, rocks at surface are weathered, rocks are
transported to form new minerals, igneous rocks are formed
*C. molten rock cools, plutonic igneous rocks are uplifted, rocks at surface are weathered,
grains are transported to form sediment, sediment is buried and cemented, metamorphic rock
forms.
D. molten rock cools, mineral rocks are formed, rocks are transported and weathered,
sedimentary rocks form and are buried where temperature and pressure increases
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25. Which of the following describes a divergent plate boundary?
A. both plates move toward the boundary; one plate sinks beneath the other
*B. both plates move away from the boundary; the gap is filled by new volcanic rock
C. many damaging earthquakes and loss of life
D. B and C are both correct
E. none of the above
26. The famous San Andreas Fault in California is an example of what type of plate boundary?
A. convergent
*B. transform
C. divergent
D. emergent
27. Match one of the terms with the following phrase. Charged subatomic particles.
A. neutrons
B. electrons
C. ions
D. protons
*E. B and D are both correct
28. Match one of the terms with the following phrase. A common island silicate that forms at
approximately 1300oC.
*A. olivine
B. feldspar
C. quartz
D. mica biotite
E. diamond
29. Match one of the terms with the following phrase. Most abundant silicate mineral in Earth’s
crust.
A. calcite
B. olivine
*C. feldspar
D. basalt
E. quartz
30. By definition, minerals have 5 required properties. Which following statement(s) is (are)
true?
A. must occur naturally and be a solid
B. must have a defined chemical composition variable within limits
C. must possess atoms in an orderly internal structure
*D. all of the above
E. none of the above
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31. Demonstrate your understanding of exchangeable cations by indicating which 2 cations can
substitute for one another in the crystal structure of the olivine family?
*A.
B.
C.
D.
Fe2+ → Mg2+
Si4+ → Al3+
Ca2+ → Na+
K+ → Mg2+
32. What is the difference between potassium feldspar and plagioclase feldspar?
A. potassium feldspar is part of Bowen’s discontinuous reaction series
B. plagioclase feldspar is part of Bowen’s continuous reaction series
C. plagioclase feldspar has high Na content at high temp and high Ca content at low temp
D. all of the above
*E. A and B only
33. Diamond and graphite are polymorphs, meaning that they share the same chemical
composition, but exhibit different physical properties. What are the crystal structures
responsible for the hardness of diamond and the softness of graphite?
A. diamond is an island silicate and graphite has a single chain structure
B. diamond has a double-chain structure and graphite is an island silicate
*C. diamond has a compact 3D structure and graphite has a loosely-spaced sheet structure
D. diamond has single-chains of silicon tetrahedra and graphite has a compact 3D structure
34. Each mineral has a crystalline structure and a chemical composition that gives it a unique
set of physical properties that we can refer to in mineral identification. What 3 properties might
you use to identify quartz?
*A. hardness of 7, colourless or light coloured, no cleavage
B. metallic lustre, hardness of 2, no cleavage
C. conchoidal fractures, colourless, specific gravity of 20
D. none of the above
35. Volcanic igneous rocks cool quickly after a volcanic eruption and exhibit a fine-grained
texture due to the short time for crystal growth. What are 2 textures of volcanic rocks?
A. aphanitic and phaneritic
B. pyroclastic and emphatic
*C. porphyritic and aphanitic
D. all of the above
E. none of the above
36. Plutonic igneous rocks contain minerals that form as magma cools underground. This
results in ____________crystals to produce a rock with a _________ texture.
A. fine, pyroclastic
*B. coarse, phaneritic
C. needle-like, aphanitic
D. a mix of large and small, porphyritic
E. large, fragmental
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37. Which of the following statement(s) is (are) correct with respect to the two volcano
photographs shown here?
A. shield volcano 1; strato-volcano 2
B. volcano 1 erupts frequently, but quietly
C. volcano 2 erupts explosively and often
*D. A and B, but not C
E. none of the above
38. Why is andesitic magma modified when it reaches the Earth’s surface?
A. because it extrudes at oceanic divergent boundaries, where seawater affects its chemical
composition
*B. because it extrudes at continental convergent boundaries, where melting of crustal rocks
affects its composition
C. because high temperatures cause chemical bonds to break during an eruption
D. because it used to be part of the volcano plug, which was pulverized during eruption
E. none of the above
39. Which statement(s) is (are) true of crystal fractionation?
A. different igneous minerals form at different temperatures
B. at different temperatures, selected elements are extracted from the liquid magma during
crystal formation
C. liquid magma composition is continually changing
*D. all of the above
E. none of the above
40. Which statement(s) accurately describe the behaviour of water during crystalization?
*A. OH- anion is a component of water and fits inside the double chain crystal structure
B. OH- anion will fit into the structure of minerals formed at very high magma temperatures
C. if groundwater comes in contact with underground magma, the volcanic eruption is stopped
D. A and C, but not B
E. none of the above
41. What is the likelihood of your finding a dark coloured, vesicular rock containing olivine
while hiking on the Canadian Shield?
A. very likely because the Canadian Shield contains lots of olivine
*B. not likely; the Canadian Shield is mostly granite
C. quite likely, since there are many active volcanoes on the Canadian Shield
D. not too common because it's likely a meteorite
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42. Volcanic mountains are found in which Canadian province?
A. Newfoundland
B. Quebec
C. Alberta
*D. British Columbia
E. none of the above
43. Examine the plate tectonic map of the world and locate the letter from A to E that is closest
to the following item. A place where plates are moving apart.
*A.
B.
C.
D.
E.
44. Examine the plate tectonic map of the world and locate the letter from A to E that is closest
to the following item. A place where you would find a well developed ophiolite sequence if you
drilled down through the crust.
A.
*B.
C.
D.
E.
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45. Examine the plate tectonic map of the world and locate the letter from A to E that is closest
to the following item. A modern day continent - continent collision.
A.
B.
*C.
D.
E.
46. Examine the plate tectonic map of the world and locate the letter from A to E that is closest
to the following item. The place with the oldest rocks.
A.
B.
C.
*D.
E.
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47. Examine the plate tectonic map of the world and locate the letter from A to E that is closest
to the following item. The place where you would most likely get nuée ardente.
A.
B.
C.
D.
*E.
48. Consider the order of crystallization of minerals from a cooling magma. Which minerals
would be most likely to coexist in the same igneous rock?
A. Calcite, K-Feldspar, Amphibole
B. Olivine, Quartz, Pyroxene
C. Ca-rich Plagioclase, Quartz, K-feldspar
*D. Ca-rich Plagioclase, Olivine, Pyroxene
49. Earth did not make it as a star. Why?
A. it warmed up at first but then lost pieces to form the moon and cooled down
*B. it lacked the mass to reach the energy required to trigger natural fusion reactions
C. it is on its way to becoming a star as soon as its internal fission reactions increase
D. it it too far from the sun
50. Knowing the definition of a calorie from your study guide, how many calories would be
required to heat 50 grams of water (50ml) from 0 degrees to 40 degrees centigrade.
A. 100
B. 200
C. 1,000
*D. 2,000
E. 90
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51. Bonus Question
Sudbury, Ontario, is recognized for its rich nickel deposits all over the world. Answering this
question might require some research beyond your course notes and textbook.
Which of the following statements is true
A. Sudbury basin was impacted by a meteorite 1. 9 billion years ago, leaving behind a 25 km
crater
B. Sudbury rocks at that time were rich in K and Ca-rich silicates
C. Sudbury rocks at that time were rich in Mg and Fe-rich carbonates
*D. Shatter cones, footwall breccia and dikes associated with the impact exist today
E. The impact produced fractures that penetrated into the core and allowed iron and nickel to
travel towards the surface.
F. more than one of the above statements is correct
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