Download Geology 101 Final (Autumn Quarter 2009) VERSION C

Geology 101 Final (Autumn Quarter 2009)
Name: ____________________
VERSION C:
Student # _____________________
Please read through the exam and answer the questions as instructed. Please give the best
answer to the question. Each question has only one correct answer.
1. The stress rate __________ the strain rate for elastic deformation.
a. is greater than
b. is less than
c. is proportional to
d. is variable compared to
e. never changes relative to
2. Where do earthquakes occur in the Pacific Northwest?
a. near the surface within the North American plate
b. deep within the Juna de Fuca plate
c. along the Cascadia subduction zone
d. all of the above are correct
e. only answers a and c are correct
3. According to Brian Atwater’s research along the Washington coastline, the recurrence interval of large
Cascadia subduction zone earthquakes is ___________.
a. ~3500 years
b. ~5000 years
c. ~10,000 years
d. ~1,000,000 years
e. none of the above recurrence intervals are correct
4.
a.
b.
c.
d.
e.
How did geologists determine the exact day of offset on the Cascadia subduction zone in 1700 AD?
they counted tree rings of dead cedar trees
they used radiocarbon dating of buried peat
they had accurate tsunami logs from Japan that recorded this event
they had accurate tsunami logs from native Americans that recorded this event
there were no records of this event
5. The Great Lakes basin presently drains through the St. Lawrence River drainage. Why will the Great
Lakes basin eventually drain south through the Mississippi River drainage?
a. The northern Great Lakes area is still isostatically rising and will change the drainage topography
b. The southern Great Lakes area is still isostatically rising and will change the drainage topography
c. The northern Great Lakes area is still isostatically subsiding and will change the drainage topography
d. The southern Great Lakes area is still isostatically subsiding and will change the drainage topography
e. The Niagra escarpment is still tectonically active and is causing the northern Great Lakes to uplift
6.
a.
b.
c.
d.
e.
Zigzag outcrop patterns are the result of ___________.
erosion of normal faults
erosion of monocline folds
erosion of symmetric anticline and syncline folds
erosion of plunging anticline and syncline
erosion of zigzag deposition features
ESS 101 Final
7.
a.
b.
c.
d.
e.
What factors influence earthquake intensity?
magnitude of the earthquake
proximity to the earthquake’s epicenter
substrate that underlies the surface
all of the above factors influence earthquake intensity
only answers a and b are correct
8.
a.
b.
c.
d.
e.
Tsunamis may be generated _________.
along vertical offset normal faults at divergent margins
along subduction zones where vertical offset has occurred on the ocean floor
along transform margins where horizontal offset has occurred on the ocean floor
submarine landslides due to seismic events
answers b and d are both correct
9.
a.
b.
c.
d.
e.
A minimum of _______ seismic stations is necessary to determine the focus of an earthquake.
3
10
1
300
5
2
10. If an earthquake occurs, the _________ waves are the first to arrive at a seismic station.
a. surface
b. shear
c. S
d. P
e. all of the seismic waves travel at the same velocity.
11. Topset beds of a delta _________.
a. are graded to the elevation of the lake or sea level
b. are deposited at the bottom of a lake embayment
c. are prograded in the direction that a stream flows into a lake
d. all of the above answers are correct
e. only answers a and b are correct
12. In order to relieve stress buildup that would cause a magnitude 7 earthquake, approximately how many
magnitude 5 earthquakes would have to occur?
a. 3
b. 30
c. 300
d. 900
e. 27,000
13. If you dated a volcanic rock that unknowingly lost argon through diffusion the resulting potassiumargon age _________.
a. would not be affected by argon loss
b. would appear older than the true age of the volcanic rock
c. would appear younger than the true age of the volcanic rock
d. would be skewed towards the argon heat loss equation
e. none of the above answers are correct
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14. A high strain rate is conducive to _______________ deformation in rock.
a. brittle fracture
b. elastic
c. ductile
d. all of the above are correct
e. none of the above are correct as strain rate has no impact on the type of deformation a rocks will
undergo
15. During offset of the Seattle Fault, 1100 years ago __________.
a. the upthrown side of the fault was uplifted ~27 feet
b. a tsunami wave was generated in the Puget Sound
c. the cause of the earthquake was movement along the Cascadia subduction zone
d. all of the above answers are correct
e. only answers a and b are correct
16. The ________ is exposed in the center of an eroding dome.
a. oldest rock
b. youngest rock
c. weakest
d. strongest
e. none of the above answers are correct
17. A reverse fault _______________.
a. may have repeating strata exposed in a vertical cross-section
b. may result in older rock units overlying younger units in a vertical cross-section
c. results primarily from tensile (extensional) stresses.
d. all of the above are correct
e. only answers a and b are correct
18. ________________ is an example of elastic deformation.
a. an over-turned fold
b. filling and emptying a reservoir
c. isostatic unloading of the earth's lithosphere following deglaciation
d. all of the above answers are correct
e. only answers b and c are correct
19. Joints facilitate weathering because ________.
a. they increase the acidity of the water
b. permit water and other chemical agents to penetrate below the surface
c. provide more surface area for the weathering front to attack
d. none of the above answers are correct
e. only answers b and c are correct
20. Why did the depth of rilling increase on the limestone boulders deposited on the three glacial moraines
we observed in lecture?
a. the lower moraine received more precipitation
b. the lower moraine was comprised of weaker limestone rock that was pre-weathered prior to deposition
c. the lower moraine was older and subjected to longer weathering
d. all of the above answers are correct
e. none of the above answers are correct
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21. Limestone will tend to precipitate in sea water when ______.
a. carbon dioxide content decreases
b. carbon dioxide content increases
c. it is agitated by wave action
d. answers a and c are both correct
e. answers b and c are both correct
22. Frost wedging occurs in rock because:
a. water contracts when it freezes to form ice.
b. water expands when it freezes to form ice.
c. water expands when it melts.
d. water will expand when it evaporates.
e. none of the above answers are correct
23. Besides frost wedging which of the following are examples of mechanical weathering?
a. oxidation of iron
b. hydrolysis reaction converting potassium feldspar to kaolinite clay
c. dissolution of calcite
d. all of the above answers are correct
e. none of the above answers are correct
24. H+ ions utilized in hydrolysis weathering reactions come from _________.
a. primordial water emitted directly from volcanic eruptions
b. hydrogen sulfide gas
c. hydrogen peroxide
d. hydrogen gas from the atmosphere
e. carbonic acid
25. Over time angular joints will become rounded due to surface weathering because _______.
a. water tends to flow in a convex manner
b. the face of the angular joint is weathered faster than the joint corner
c. the edge of the angular joint is weathered faster than the joint corner
d. the corner of the angular joint is weathered faster than the joint edge or face
e. none of the above answers are correct because joint blocks become more angular over time
26. Which of the following transport agents generally results in cross beds?
a. wind
b. turbidity currents
c. rivers
d. glaciers
e. answers a and c are both correct
27. What test would conclusively tell you that marble and limestone are both composed from the mineral calcite?
a. color
b. taste
c. hardness
d. reaction with HCl acid
e. the number of cleavage planes
28. Chert generally precipitates in deep ocean water because ________.
a. calcium carbonate precipitates in cold water
b. silica is less soluble (dissolvable) in cold water
c. silica is more soluble (dissolvable) in cold water
d. organisms that secrete silica only live in deep water
e. none of the above answers are correct
ESS 101 Final
29. Monocline folds result from ____________.
a. bi-directional stresses
b. uni-directional stresses
c. extensional stresses
d. erosion of plunging (tilted) anticlines and synclines
e. ersoion of tilted strata
30. Oolites form from _______.
a. precipitation of silica around sand grains oscillated by waves
b. precipitation of calcite around sand grains oscillated by waves
c. iron oxide mottles in the B horizon of a soil
d. burrowing tubes from marine forams
e. none of the above answers are correct
31. A sedimentary rock unit with graded beds that fine towards the base would indicate __________.
a. that the rock unit has not been deformed (remains right-side up)
b. that the rock unit was tilted vertically
c. that the rock unit was overturned (upside down)
d. that the rock unit has been buried
e. all of the above answers could be correct
32. If a fault offset two landslide deposits that are radiocarbon dated at 15,000 and 12,000 years old,
respectively, one can infer that the faulting event ________.
a. is younger than 12,000 years old
b. is older than 12,000 years old
c. is older than 15,000 years old
d. is younger than 15,000 years old and older than 12, 000 years old
e. the relative age of the fault cannot be determined by this cross-cutting relationship
33. What type of geologic structure is conducive to trapping oil if a cap rock exists?
a. plunging syncline
b. monoline
c. strike-slip fault
d. anticline
e. non-plunging syncline
34. According to the principle of inclusions the age of a xenolith found within an intrusive (plutonic)
igneous rock ________.
a. would be older than the intrusive rock.
b. would be younger than the intrusive rock
c. would be the same age as the intrusive rock
d. could be older or younger than the intrusive rock depending upon its source magma
e. the age of a xenolith is better described by the principle of cross-cutting relations
35. How might you recognize in the field that a disconformity exists between two sequences of rock?
a. you might observe a buried soil or weathering zone between the two units
b. you would find unmetamorphosed sedimentary rock in direct contact with an igneous pluton
c. the sediment grain size will always vary between the two units
d. you might observe fossils that are not temporally (time) compatible between the two rock units.
e. answers a and d are both correct
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ESS 101 Final
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36. High temperature is conducive to ______________ deformation in rock.
a. brittle fracture
b. elastic
c. ductile
d. all of the above are correct
e. none of the above answers are correct
37. Radiocarbon ages can be determined _________.
a. directly counting Beta particles emitted during radioactive decay of C-14
b. measuring the ratio of 14C to its stable isotopic equivalents (13C or 12C)
c. measuring the ratio of 14C to its daughter product 14N
d. all of the above answers are correct
e. only answers a and b are correct
38. Where is radiocarbon first produced on earth.
a. in coal deposits
b. in the atmosphere
c. in plants
d. in phytoplankton
e. it is derived from carbon-based meteorites
From the diagram of the Basin and Range Province (Nevada and Utah) shown below answer questions 39-42.
39. What kind of faults bound mountains and valleys of the Basin and Range province in Nevada and Utah?
a. reverse faults
b. normal faults
c. strike-slip faults
d. transform faults
e. oblique faults
40. What kind of stress would you expect to cause this type of faulting?
a. shear
b. tensile (extension)
c. compressional
d. rotational
e. lateral
41. At what kind of plate margin would you expect to find this type of fault?
a. divergent
b. convergent
c. transform
d. subduction
e. none of the above
42. What hypothesis did we discuss to explain Basin and Range tectonics (i.e., to explain why a divergent margin
might be forming under Nevada and Utah)?
a. delayed reaction due to the separation of Pangaea
b. the spreading ridge was subducted under California and is now positioned under Nevada and Utah.
c. bolide (meteorite) impact
d. compressive stresses linked to microterrane collisions of the coast of Washington
e. all of the above
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43. Overturned folds may evolve into _________.
a. thrust faults
b. normal faults
c. strike-slip faults
d. transform faults
e. oblique faults
44. Cross-bedding within sediment tends to occur __________.
a. in wind-blown sand dunes
b. migrating stream channels
c. from wave oscillation along shorelines
d. all of the above are correct
e. only answers a and b are correct
45. Which metamorphic rock has been subjected to contact metamorphism (not foliated)?
a. slate
b. schist
c. quartzite
d. gneiss
e. all of the above metamorphic rocks have been subjected to contact metamorphism
Laboratory Questions
46. What is the difference between relative and numerical dating?
a. relative dating uses isotopic decay to calculate the age and numerical dating uses the fossil record to
determine the age range.
b. relative dating uses stratigraphic principles and the fossil record to put deposits and events in order,
numerical dating uses isotopic decay to determine the age.
c. relative dating is an estimate of the age based on stratigraphic principles and isotopic decay while
numerical dating uses the fossil record to precisely compute the age.
d. relative dating is illegal (at least if they are closer than your cousin) and numerical dating is done by computer
dating services.
e. none of the above answers are correct
47. In metamorphic rocks with foliation, the texture develops as a result of:
a. the alignment of platy (flat) minerals perpendicular to the maximum pressure on the body of rock.
b. the rock mass melting and then solidifying.
c. factors unrelated to metamorphic processes.
d. lithostatic pressure.
e. all of the above are correct.
48. What diagnostic criteria did you use to identify sedimentary breccia:
a. tiny clay-sized particles
b. large rounded clasts within the rock matrix
c. large angular clasts within the rock matrix
d. reaction with HCl
e. stratified layers
49. Which of the following conditions on a slope will increase the likelihood of landslides?
a. increasing the slope angle
b. saturating the soil
c. increasing the weight on the slope
d. removing the vegetation on a slope
e. all of the conditions would increase the likelihood of landslides
ESS 101 Final
Bonus Questions (5 questions)
50. Who was our first guest speaker right after the midterm?
a. Seth Hammond
b. Bethany Swanson
c. Jim Goldschmidt
d. Graham Sonata
e. Haffah Gniess Dae
51. We discussed B horizon subscripts briefly during our soils lecture. What does Bw and Bk represent?
a. reddening due to iron oxide and kaolinite in the B horizon
b. accumulated water and kaolinite in the B horizon
c. accumulated water and calcium carbonate in the B horizon
d. accumulated aluminum and kyanite in the B horizon
e. reddening due to iron oxide and calcium carbonate in the B horizon
52. What is Terry’s favorite ice cream?
a. Chocolate
b. Mocha
c. Rocky Road
d. Lemon Custard
e. Black Licorice
53. We discussed the Ione Formation located in California. What type of climatic regime did the Ione
oxisol form 38 million years ago?
a. Mediterranean
b. tropical
c. arid
d. maritime temperate
e. subpolar
54. What was Terry’s favorite Thanksgiving dish?
a. turkey and mashed potatoes
b. candied yams
c. sage dressing
d. pumpkin pie
e. glazed cranberries
Please sign this exam below with your normal signature:
_____________________________
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