Download Practice Test – Geology 106, Chapter 19 from The Changing Earth

Practice Test – Geology 106, Chapter 19 from The Changing Earth
written and formatted by Joseph Wilkinson
1. The Earth was originally heterogeneous/homogeneous and cool/hot (circle correct
answers).
2. The Earth’s oceans were formed by _______________ BYa, mainly by
_______________ and the expulsion of _______________ (both during volcanic
eruptions).
3. Why did vendian organisms and shelly invertebrates replace earlier Precambrian
organisms?
4. Early life and the advent of photosynthesis hindered/contributed to (circle correct
answer) the formation of an oxygen-rich atmosphere on Earth.
5. The formation of amino acids – the “building blocks” of life on Earth – required
three elements: _______________, _______________, and _______________.
A scientist named _______________ documented the formation of amino acids
under these conditions in a laboratory.
6. Are fossils from the Precambrian Era common? Why or why not?
7. Life began in the oceans because water provided protection from ultraviolet rays
before the widespread formation of ozone (O3) in the atmosphere. TRUE/FALSE
8. What are the chemical elements essential to the formation of life?
_______________, _______________, _______________,
_______________, _______________, and _______________.
9. There are no rocks from the Hadean Period. TRUE/FALSE
10. Fossilized green algae found in the _______________ (rock formation) of
_______________ (geographic location) and dated between _______________
and _______________ billion years old represent the first evidence of sexual
reproduction.
11. What is the albedo effect?
12. The Earth’s crust probably formed and reassimilated with the mantle several times
between _______________ and _______________ BYa. Geologists call this
time the _______________.
13. By the end of the Cambrian Period, eight invertebrate phyla dominated the fossil
record. TRUE/FALSE.
14. The shelly fauna of the Cambrian Period were at an evolutionary advantage,
primarily because their shells provided ______________________________,
______________________________, ______________________________,
______________________________, and
______________________________.
15. Cryptozoic glaciation around 2.2 BYa produced the _______________ Formation
of tillite.
16. Describe photochemical dissociation and provide three chemical reactions involving
the process.
17. The inner, terrestrial planets have densities ranging from _______________ to
_______________ g/cm3, while the outer, gaseous planets have densities from
_______________ to _______________ g/cm3. Density increases/decreases
(circle correct answer) as planets near the sun.
18. Name five types of life-atmosphere exchanges.
______________________________, ______________________________,
______________________________, ______________________________,
and ______________________________.
19. Comets are large/small with high/low densities (circle correct answers). They are
composed of _______________ and _______________.
20. The Earth’s present atmosphere includes _______________% Nitrogen (N2) and
_______________% Oxygen (O2).
21. Earth would have a carbon dioxide rich atmosphere if not for the storage of CO2
during the creation of limestone (CaCO2). TRUE/FALSE
22. Describe and explain this solar system’s asteroid belt.
23. The Earth had a distinct core and mantle by _______________, but did not have a
consistent, stable crust until _______________. The separation of the Earth into
distinct parts was caused by the heating of the planet, and is known as
______________________________.
24. Name three types of ocean-sediment exchanges.
______________________________, ______________________________,
and ______________________________.
25. In the early days of the solar system, solar materials combined (accreted) to form
first _______________, then _______________, then _______________
through their increased gravitational pull.
26. The fossil record of the Cryptozoic Eon is characterized by many/few fossils,
many/few outcrops, and highly/slightly distorted rocks. This makes interpretation
difficult/easy.
27. Name six energy sources that could have aided the origin of life on Earth.
_______________, _______________, _______________,
_______________, _______________, and _______________.
28. What is the age of the oldest discovered sedimentary rocks? _______________
29. How did photochemical dissociation affect life on Earth?
30. Isotopic dates obtained from detrital zircons found in the _______________
(rock formation) of _______________ (geographic location) put the zircons at
_______________ years old, and prove that by the time that those zircons
formed, the Earth’s crust had formed and was being eroded.
31. The Copper Belt of _______________ (African country) produces
_______________% of the world’s copper and _______________% of the
world’s cobalt.
32. The _______________ Range in the state of _______________ was a major site
of taconite deposition during the Great Iron Age _______________ BYa.
33. In North America, Precambrian rocks are found in
______________________________, ______________________________,
and ______________________________. Provide examples of each type of
location: ______________________________,
______________________________, and
______________________________ respectively.
34. Define the terms outgassing and juvenile water. What do they have to do with
each other?
35. Name three methods by which the current theories about the interior of the Earth
were determined. _______________, _______________, and
_______________.
36. Carbon spheres from _______________ (geographic location) and dated
_______________ BYa represent the first evidence of life on Earth.
37. Carbon dioxide (CO2) was abundant/rare during the Cryptozoic Eon, so the
temperatures are thought to have been cold/warm (circle correct answers).
38. The Earth’s mantle constitutes _______________ of the planet by volume and
_______________ by mass.
39. The dominant marine fossils during the Cambrian Period were the
_______________, which accounted for about _______________% of that
period’s fossil record, followed by the _______________, which accounted for
about _______________%.
40. Name four geologic formations that provide evidence regarding the Earth’s climate
during the Cryptozoic Eon. _______________, _______________,
_______________, and _______________.
41. Explain the most current theory about the formation of the Earth’s moon.
42. 95% of the universe is composed of two elements: _______________ and
_______________. Elements other than these first two evolved from
_______________ through a process known as a) thermonuclear reactions, b)
revised nebular reactions, c) impact reactions, or d) chain reactions.
43. Metallic meteorites are thought to be core fragments from an ancient planet.
TRUE/FALSE
44. Name the three most abundant compounds in the Earth’s present atmosphere.
_______________, _______________, and _______________.
45. Define terrane.
46. Moving from the Earth’s crust to its center (core), density increases/decreases,
temperature increases/decreases, and pressure increases/decreases.
47. The first self-sustaining organisms lived on materials dissolved in the oceans.
TRUE/FALSE
48. The worldwide glaciation from 800 to 700 MYa is known as the
______________________________.
49. Explain what happened to the Helium (He) and Hydrogen (H) left in the Earth’s
atmosphere after the formation of the solar system.
50. Name three ways by which the Earth was heated before the Archean Period.
_______________, _______________, and _______________.
51. The current model for the origin of the solar system is called a) the revised nuclear
hypothesis, b) the simultaneous propagation theory, c) Planck’s Genesis Theory, or
d) the revised nebular hypothesis.
52. The formation of a) ozone (O3), b) carbon dioxide (CO2), c) methane (CH4), or d)
ammonia (NH3) in the Earth’s early atmosphere contributed to the development of
life by protecting the Earth’s surface from ultraviolet waves.
53. Describe in detail the history of the Precambrian strata of the Grand Canyon.
54. The origin of life required a temperature between _______________ and
_______________ degrees Celsius.
55. What is the Earth’s “total” or “average” density? _______________
56. What were the three compounds most abundant in the Earth’s early atmosphere?
_______________, _______________, and _______________.
57. The oldest probable fossilized organisms are cyanobacteria (stromatolites)
discovered in the _______________ (rock formation) from
______________________________ (geographic location) dated between
_______________ and _______________ BYa.
58. What does the revised nebular hypothesis propose?
59. The Paleozoic Era accounts for over 90% of the Earth’s history. TRUE/FALSE
60. Metallic meteorites are comprised of the metals _______________ and
_______________. They have a density of _______________ and constitute
_______________ of all meteorites to hit the Earth’s surface. Stony meteorites
have a density of _______________ and constitute _______________ of all
meteorites to hit the Earth.
61. The shelly fauna of the Precambrian and early Cambrian built their shells of
_______________, _______________, or _______________.
62. Taconite deposits from the Cryptozoic Eon have only been found in North America.
TRUE/FALSE
63. Africa is the world’s largest producer of gold, cobalt, chromium, and diamonds.
TRUE/FALSE
64. List the four rock formations that form the Unkar Group of the Grand Canyon:
_______________, _______________, _______________, and
_______________. These rocks are _______________ billion years old and are
igneous/metamorphic/sedimentary (circle correct answer).
ANSWERS:
1. homogeneous and cool.
2. 3.7 BYa; outgassing and the expulsion of juvenile water.
3. Vendian organisms and shelly invertebrates replaced earlier Precambrian organisms
after the almost-global Varangian glaciations almost wiped out all life on the planet
Earth. The retreat of the Varangian glaciers coincided with a dramatic rise in
atmospheric oxygen and tectonic movement, creating numerous shallow seas on the
surface of the Earth – this was conducive to the development of life. An increase
in the availability of the nutrients with which the shelly invertebrates built their
shells helped them to survive, and the predation of the shelly invertebrates upon
Precambrian stromatolites hastened the demise of said stromatolites.
4. contributed to.
5. essential elements, proper temperature, and an energy source; Stanley Miller.
6. Fossils from the Precambrian Era are very rare, because the organisms of that time
were predominantly microscopic and soft-bodied, and because many of the fossils
that were created were then destroyed by erosion (there is an unconformity
between the Precambrian Era and the Cambrian Period in many places ) or by
metamorphism.
7. TRUE.
8. Hydrogen (H), Carbon (C), Nitrogen (N), Oxygen (O), Phosphorus (P), and Sulfur (S).
9. TRUE; the Earth did not have a stable and consistent crust until 4.0 BYa (the
beginning of the Archean Era).
10. the Beck Springs Dolomite of California; 1.4 and 1.2 BYa.
11. The albedo effect is a measure of the reflectivity of a surface. If it snows on an
area, then that area becomes colder due to the reflective nature of the color
white, which prevents the sun’s rays from heating the Earth’s surface in that area.
This process causes glaciation.
12. 4.0 and 4.55 BYa; the Hadean Period of the Precambrian Era.
13. TRUE.
14. protection against solar radiation; protection from drying out in the intertidal zone;
protection from predators; structural support; sites for the attachment of muscles
to aid in locomotion (this could fall under “structural support”).
15. Gowganda Formation.
16. Photochemical dissociation is the dissociation by ultraviolet rays of compounds in
the Earth’s atmosphere into other, simpler compounds. Examples of this include:
2H2O
2H2 + O2
CH4 + 2O2
4NH3 + 3O2
CO2 + 2H2O
2N2 + 6H2O
17. 5.1 to 5.5 g/cm3; 0.71 to 2.47g/cm3; increases.
18. cycling of N by bacteria; plants consume CO2 and produce O; animals consume O and
produce CO2; oxygen-fixing bacteria consume O; coal and carbonate rocks store C.
19. small with low densities; ice and stony materials.
20. 78% N and 21% O.
21. TRUE.
22. The asteroid belt is a massive collection of individual asteroids in orbit around the
sun between Mars and Jupiter. They are currently thought to be planetesimals
that were prevented from accreting into protoplanets and planets by Jupiter’s
gravitational field.
23. 4.55 BYa, 4.0 BYa; differentiation based on density.
24. storage of Ca and CO2 in limestone (CaCO2); storage of Ca and SO4 in anhydrite
(CaSO4); storage of Na and Cl in rock salt (NaCl).
25. planetesimals, then protoplanets, then planets.
26. few fossils, few outcrops, highly distorted (deformed, faulted, folded,
metamorphosed, etc.) rocks; difficult.
27. solar radiation, volcanism, electrical discharges, hot springs, radioactive decay, and
black smokers.
28. 3.7 billion years old (the same age as the Earth’s oceans).
29. Photochemical dissociation allowed methane (CH4) and ammonia (NH3) – both
compounds toxic to life – to be converted into carbon dioxide (CO2), nitrogen gas
(N2), and oxygen gas (O2), thus generating compounds necessary to life as we know
it.
30. Acasta Gneiss of Northwest Canada; 3.96 billion years old.
31. Zambia; 25%, 25%.
32. Mesabi Range, Minnesota; 2.2 BYa.
33. shield areas (exposed cratons), deep canyons, and the cores of old mountain belts;
the Canadian Shield, the Grand Canyon, and the Appalachians respectively.
34. Outgassing is the expulsion of gases from the Earth’s interior to the atmosphere.
Steam (H2O) is among those gases; that steam is known as juvenile water.
35. density data, seismic data, and dynamo theory.
36. Greenland; 3.85 BYa.
37. abundant; warm.
38. 82% and 67%.
39. the trilobites, 60%; the brachiopods, 20%.
40. mudcracks, dune deposits, glacial evidence, and evaporites.
41. It is currently thought that the moon formed when an asteroid impact sent Earth
material flying into orbit. This material gradually accreted to form a single solid
mass with its own gravitational field.
42. Hydrogen (H) and Helium (He); Hydrogen (H); A (thermonuclear reactions).
43. TRUE. Stony meteorites are thought to be fragments from the mantle of another –
or maybe the same – planet.
44. Nitrogen (N2), Oxygen (O2), and carbon dioxide (CO2).
45. A terrane is an exotic landmass; a named part of an existing continent that may
have once been a continent (or a microcontinent) in its own right before accreting
onto a larger landmass.
46. increases, increases, increases.
47. FALSE; the first truly self-sustaining organisms lived by photosynthesis.
48. Varangian Glaciation.
49. The Helium (He) was too light to be trapped in the Earth’s gravitational field, so it
left the planet’s atmosphere. The Hydrogen bonded with Oxygen to form water
(H2O), which was heavy enough to be retained by the Earth’s gravity.
50. gravitational contraction, radioactive decay, and meteor impacts.
51. D (the revised nebular hypothesis).
52. A (Ozone – O3).
53. The Precambrian materials of the Grand Canyon consist of the Vishnu Schist (1.7
BY) intruded by the Zoroaster Granite. These materials were uplifted to form the
Vishnu Mountains, which were then eroded. The erosion surface was buried by the
sedimentary rocks of the Unkar Group (0.8 BY), creating an unconformity. All
materials were uplifted and eroded, producing a surface upon which Paleozoic
strata were deposited.
54. 0 and 100 degrees Celsius.
55. 5.5 g/cm3.
56. methane (CH4), ammonia (NH3), and steam (H2O).
57. the Warrawoona Group from North Pole, Australia; dated from 3.5 to 3.3 BYa.
58. The revised nebular hypothesis suggests that the sun, the planets, and the rest of
our solar system came to be simultaneously, and that the current planets were
created through accretion of solar materials which combined to form planetesimals,
then protoplanets, then planets as their gravitational pull increased and attracted
more materials.
59. FALSE; the Precambrian Era accounts for over 90% of the Earth’s history.
60. Iron (Fe) and Nickel (Ni); 7.6 g/cm3; 25%.; 3.5 g/cm3; 75%.
61. silica, chitin, or calcium.
62. FALSE; taconite deposits have been found in the United States, Australia, Canada,
India, Sweden, Russia, Venezuela, and Brazil.
63. TRUE; South Africa produces 75% of the world’s gold, the Democratic Republic of
the Congo is the world’s largest producer of cobalt, and Zimbabwe is the world’s
largest producer of chromium.
64. the Bass Limestone, the Shinumo Quartzite, the Hakatai Redbeds, and the Dox
Sandstone; 0.8 billion years old; sedimentary.