Name:_________________________
Historical Geology Exam I: Spring 2008
Each answer is worth 2 points; sometimes you will have to select the best answer
1. In what environment is the Eagle Sandstone, which forms the rim rock of the Yellowstone river valley in Billings,
thought to have formed?
a. River delta
b. Continental lacustrine
c. Barrier beach islands
d. Western Interior Seaway
2. How old is the universe?
a.
b.
c.
d.
e.
~540 Million years
~2 to 2.5 Billion years
~3.8 Billion years
~4.6 Billion years
~15 Billion years
3. How old is the Solar System?
a.
b.
c.
d.
e.
~540 Million years
~2 to 2.5 Billion years
~3.8 Billion years
~4.6 Billion years
~15 Billion years
4. When was the last major period of ‘cataclysmic bombardment’ by meteorites?
a.
b.
c.
d.
e.
~540 Million years ago
~2 to 2.5 Billion years ago
~3.8 Billion years ago
~4.6 Billion years ago
~15 Billion years ago
5. When did atmospheric Oxygen begin to increase?
a.
b.
c.
d.
e.
~540 Million years ago
~2 to 2.5 Billion years ago
~3.8 Billion years ago
~4.6 Billion years ago
~15 Billion years ago
6. What is the composition of the Sun?
a.
b.
c.
d.
Hydrogen and Helium
Iron and Silicates
Silicon and Oxygen
Nitrogen and Oxygen
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7. Which are the terrestrial inner planets?
a.
b.
c.
d.
Jupiter, Saturn, Neptune, and Uranus
Mars, Jupiter and Saturn
Venus, Earth, Mars and Jupiter
Venus, Earth, Mars and Mercury
8. Of what are the terrestrial inner planets composed?
a.
b.
c.
d.
Hydrogen and Helium
Iron and Silicates
Carbon, Nitrogen and Oxygen
Methane, Ammonia and Water
9. Which are the outer gaseous giants?
a.
b.
c.
d.
Jupiter, Saturn, Neptune, and Uranus
Mars, Jupiter and Saturn
Venus, Earth, Mars and Jupiter
Venus, Earth, Mars and Mercury
10. Of what are the outer gaseous giants composed?
a.
b.
c.
d.
Hydrogen and Helium
Iron and Silicates
Silicon, Oxygen, Aluminum, Calcium and Magnesium
Methane, Ammonia and Water
11. How was the Earth’s moon formed?
a.
b.
c.
d.
The Moon is a captured asteroid
The collision between the Earth and a mars sized object
Agglomeration of meteorites in the Early Solar System
It condensed in the original solar nebula
12. Why don’t we see a lot of meteorite craters on the surface of the Earth?
a.
b.
c.
d.
They were destroyed as ancient crust was recycled during subduction and burial
The Earth was protected from late-stage meteorite impacts by the Moon
They are gone because of erosion and burial
Only a and c are correct
13. What is a silica tetrahedron?
a.
b.
c.
d.
e.
The most common constituent of the Earth’s crust
A regular 4-sided form with 1 Oxygen in the center of 4 Silicon atoms at the corners
A regular 4-sided form with 1 Silicon in the center of 4 Oxygen atoms at the corners
Only a and b are correct
Only a and c are correct
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14. What causes igneous rock textures to be either fine- or coarse-grained?
a.
b.
c.
d.
Composition of the magma
Temperature of the magma
Rate at which the magma cools
Whether the right chemicals are present to form porphyroblasts
15. What is ‘porphyritic’ texture?
a.
b.
c.
d.
A large crystal in a fine grained matrix of an igneous rock
Crystals that are too small to be seen by the naked eye
Crystals that are large enough to be seen by the naked eye
A large crystal in a fine grained matrix of an sedimentary rock
16. What are the differences and similarities between basalt and rhyolite?
a.
b.
c.
d.
They have the same texture, but different compositions
They have the same composition, but different textures
Basalt is an igneous rock and rhyolite is a metamorphic rock
Rhyolite is an igneous rock and Basalt is a metamorphic rock
17. What are the differences and similarities between granite and rhyolite?
a.
b.
c.
d.
They have the same texture, but different compositions
They have the same composition, but different textures
Granite is an igneous rock and rhyolite is a metamorphic rock
Rhyolite is an igneous rock and granite is a metamorphic rock
18. What is the process called that allows a single magma to produce igneous rocks of different compositions?
a.
b.
c.
d.
Magma differentiation
Subduction
The rock cycle
Weathering and/or metamorphism
19. What is metamorphism?
a.
b.
c.
d.
The alteration of a rock due to oxidation and acid dissolution
The alteration of a rock due to high temperatures and pressures
The alteration of a rock due to physical and chemical weathering
None of the above
20. What produces foliation in metamorphic rocks?
a.
b.
c.
d.
Hydrothermal fluids
Hydrostatic Pressure
Directed Pressure
Platy minerals formed during the Bowen’s Reaction Series
3
21. What is the most important geologic agent in eroding, transporting and depositing sediment?
a.
b.
c.
d.
e.
Oxidation
Acid rain
Water
Wind
Global Warming
22. What is a floodplain?
a.
b.
c.
d.
The outwash from a rapidly melting glacier
It is the distributary delta of a river that forms during spring floods
Barrier beach islands that are created during spring floods
The flat area on the sides of rivers where fine-grained muds are deposited during floods
23. What is a delta?
a.
b.
c.
d.
The deposit formed when a river dumps its sediment into a lake of ocean
The bedding associated with a point bar
Beds which intersect at a angle to one another
Western Interior Seaway
24. What are the two main types of weathering?
a.
b.
c.
d.
Physical and Chemical
Oxidation and Acid Dissolution
Biologic and non-Biologic
Regional and Contact
25. What is the Bowen’s reaction series?
a.
b.
c.
d.
The sequence of minerals formed during progressive metamorphism
The series of facies in a transgressive sequence
The sequence of minerals that weather as an igneous rock weathers
The sequence of minerals that crystallize as a magma cools
26. Which of the following are sedimentary rocks?
a.
b.
c.
d.
e.
Basalt, Gabbro, and Dacite
Rhyolite, Andesite and Granite
Sandstone, Shale, and Limestone
Coal, Dolostone and diatomite
Both C and D are correct
27. What is a turbidite?
a.
b.
c.
d.
A rock formed from a debris flow coming off of the continental margin
A rock formed from a debris flow flowing out of a river mouth
A rock formed from a flood deposit
Any rock formed from a turbid (debris-filled) fluid
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28. In what sedimentary environments are cross-beds formed?
a.
b.
c.
d.
Lakes and Oceans
In glacial outwash and tills
In rivers, sand dunes and beaches
In evaporite basins
29. What are the three most common sedimentary rocks (IN ORDER)?
a.
b.
c.
d.
Shales are most common, then Sandstones followed by Limestones
Sandstones are most common, then Shales followed by Limestones
Limestones are most common, then Shales followed by Coals
Shales are most common, then Limestones followed by Dolomites
30. What do Sedimentary Rocks Record?
a.
b.
c.
d.
e.
Depositional Environment
Diagenesis (what happened after deposition)
Source (Provenance) of sediment
Erosion and Transport Agent
All of the above
31. What are the two main types of chemical weathering?
a.
b.
c.
d.
Oxidation and acid dissolution
Pressure release and frost action
Dissolving in water
Acid rain and Frost action
32. Place the following minerals in order from least easily weathered to most easily weathered:
a.
b.
c.
d.
e.
Iron oxide (hematite), Quartz, Olivine, Calcite, Halite.
Quartz, Iron oxide (hematite), Olivine, Calcite, Halite.
Quartz, olivine, calcite, halite, Iron oxide (hematite),.
Halite, Calcite, Olivine, Quartz, Iron oxide (hematite)
Quartz, Iron oxide (hematite), Halite, Olivine,
33. What characteristics are used to identify how mature sediment is?
a.
b.
c.
d.
e.
Foliation and Composition
Composition and Crystallinity
Rounding, Sorting, Size and Composition
How far it is from its source
Textural characteristics such as Aphanitic and Phaneritic textures
34. In what environments are sands deposited?
a.
b.
c.
d.
Rivers and Beaches only
Rivers, Beaches and Deserts
Deep Ocean basins and Mid ocean ridges
Both B and C are correct
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35. In what environments are Shales usually formed?
a.
b.
c.
d.
e.
Rivers
Rivers, Beaches and Deserts
Barrier beach islands
In the ocean, relatively far from the shore
At mid-ocean ridges
36. In what environments are most Limestones formed?
a.
b.
c.
d.
In low latitude oceans, near the shore
In high latitude oceans, near the shore
In the ocean, near river mouths where detrital calcite collects
In lakes
37. In what environments are Coals formed?
a.
b.
c.
d.
Rivers
A swamp, bog or other plant-rich environments
A barrier beach island
Evaporite basins and lakes
38. What are Heinrich events?
a.
b.
c.
d.
e.
Warming periods accompanied by massive ice berg calving and deposition of dropstones and gravels
Warming periods caused by increased volcanism, i.e. volcanoes
Cooling periods accompanied by massive ice berg calving and deposition of dropstones
Cooling periods caused by Milankovitch cycles
Changes in climate accompanied by shifts in carbon-14 isotopes
39. What is a trace fossil?
a.
b.
c.
d.
A carbonized trace of a leaf fossil
Fossilized evidence of an organism that does not include the organism’s body or skeleton
Fossils of slugs, jellyfish and other ‘soft parts’ of plants and animals
Fossilized trace of an organism including the body and/or skeleton
40. How old are the oldest verified fossilized ‘human’ footprints?
a.
b.
c.
d.
~6000 years
~20,000 years
~350,000 years
> 65 million years
41. In what environments do we find asymmetric ripples?
a.
b.
c.
d.
In lakes
Any sedimentary deposit where there is back and forth motion of wind or water (i.e. waves)
Any sedimentary deposit where there is unidirectional motion of wind or water (i.e. currents)
Shallow water areas where muds occasionally dry up and shrink
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42. What is the ‘principle of cross-cutting relationships’?
a.
b.
c.
d.
Cross-cutting beds can be used for dating if they are volcanic ashes containing feldspars
Cross-cutting beds can be used to date the sediments that include them
Cross-cutting beds are older than the sediments that include them
Cross-cutting beds are younger than the sediments that include them
43. What is the principle of faunal succession?
a.
b.
c.
d.
Organisms become more complex over time
Organisms succeed through ‘natural selection’
Fossils succeed each other vertically in a specific, reliable order that can be identified over wide horizontal
distances
Fossils can be successfully used to place absolute ages on the rocks that contain them
44. What is a Diatom?
a.
b.
c.
d.
A calcareous phytoplankton (photosynthetic marine micro-organism)
A siliceous phytoplankton (photosynthetic marine micro-organism)
A calcareous zooplankton (heterotrophic marine micro-organism)
A siliceous phytoplankton (heterotrophic marine micro-organism)
45. What is a Foraminifera?
a.
b.
c.
d.
A calcareous phytoplankton (photosynthetic marine micro-organism)
A siliceous phytoplankton (photosynthetic marine micro-organism)
A calcareous zooplankton (heterotrophic marine micro-organism)
A siliceous phytoplankton (heterotrophic marine micro-organism)
46. What is an unconformity?
a.
b.
c.
d.
A surface separating two rock strata of different lithologies
A erosional or non-depositional surface separating two rock strata of different ages
A surface separating two rock strata with different fossil assemblages
A surface separating two rock strata with different magnetic orientations
47. What is a disconformity?
a.
b.
c.
d.
An unconformity where the two rock strata intersect at an angle
An unconformity where the two rock strata are approximately parallel to one another
A surface separating two rock strata with different fossil assemblages
A surface separating two rock strata of different lithologies
48. What is Walther’s Law?
a.
b.
c.
d.
Sediments were originally laid down horizontally on top of one another
Adjacent sedimentary facies end up stacked on top of one another during either a transgression or
regression
The oldest beds are at the bottom
The youngest beds are at the bottom
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49. What is a transgression and how do we recognize these in rock outcrops?
a.
b.
c.
d.
An increase in relative sea level resulting in a fining upward sequence
An increase in relative sea level resulting in a coarsening upward sequence
An decrease in relative sea level resulting in a fining upward sequence
An decrease in relative sea level resulting in a coarsening upward sequence
50. How much has sea level changed in the last 100 years?
a.
b.
c.
d.
~ 150-200 millimeters
~ 150 centimeters
~ 6 meters
~ 120 meters
51. How much has sea level changed since the last Glacial Maximum (~18,000 years ago)?
a.
b.
c.
d.
~ 150-200 millimeters
~ 150 centimeters
~ 6 meters
~ 120 meters
52. What are Milankovitch Cycles?
a.
b.
c.
d.
Cyclic variations in sea level
Cyclic variations in sedimentary facies
Variations in global temperatures
Variations in the orbital parameters of the Earth
53. How have Milankovitch Cycles affected global climates?
a.
b.
c.
d.
They have impacted the amount of sunlight reaching the high latitudes thus affecting melting of glacial ice
They affected the amount of radiation given off by the Sun causing warming and cooling cycles on Earth
They caused changes in springtime floods and sea levels
They caused the present increase in global temperatures
54. What are the oxygen isotope stages?
a.
b.
c.
d.
Systematic variations in oxygen isotopes that are used to date ocean sediments due to variations in oxygen
isotopes of seawater during glacial/interglacial stages
Absolute ages of oxygen-bearing minerals due to decay of radioactive elements
Systematic variations in oxygen isotopes that are used to date ocean sediments because of variation in
deuterium ratios of ocean water
Systematic variations in oxygen isotopes that are used to date ocean sediments due to decay of unstable
oxygen-18
55. What is the difference between absolute and relative dating of rocks?
a.
b.
c.
d.
Absolute ages give an actual age for a rock; relative ages give ages of rocks relative to one another
Relative ages give an actual age for a rock; absolute ages give ages of rocks relative to one another
Absolute ages are determined using certain radioactive isotopes; relative ages are determined using various
stratigraphic methods such as fossils, lithology and magnetostratigraphy
Both A and C are correct
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56. What instrument is used to determine isotope ratios?
a.
b.
c.
d.
A gas chromatograph
An ionizing photomultiplier
A mass spectrometer
A scintillation counter
57. Which radioactive isotopes can be used to date rocks from the Cambrian Period?
a.
b.
c.
d.
e.
Carbon-14
The Uranium-Lead Series
Potassium-Argon Isotopes
Oxygen Isotopes
B and C only
58. What happens at a divergent plate boundary?
a.
b.
c.
d.
Plates collide forming a subduction zone
Plates collide forming a mountain range
Plates spread apart forming a Mid Ocean ridge and potentially a new ocean
Either A or B
59. What occurs at a convergent plate boundary?
a.
b.
c.
d.
Plates collide forming a subduction zone
Plates collide forming a mountain range
Plates spread apart forming a Mid Ocean ridge and potentially a new ocean
Either A or B
60. What is an isotope?
a.
b.
c.
d.
e.
An element that has the same number of neutrons but a different number of protons
An element that has the same number of protons but a different number of neutrons
An element that has the same number of neutrons but a different number of electrons
An element that breaks down due to radioactivity
An element that is stable
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