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The Earth Through Time
CHAPTER 13—MESOZOIC EVENTS
Multiple Choice Questions
Select the best answer.
1.
What is the major tectonic event at the Mesozoic?
a. Forming of Pangea
b. Breakup of Pangea
c. Breakup of Rodinia
d. Gondwana collided into Antarctica
e. Avolonia collided with North America
2.
Which of the following were new vertebrate classes that appeared in the
Mesozoic?
a. Birds
b. Mammals
c. Dinosaur
d. Amphibians
e. Both a. and b.
3.
The first stage of the breakup of Pangea involved __________________.
a. the Atlantic rift begin to extend northward
b. opening of oceanic tracts between Africa and Antarctica
c. separation of North America from Gondwana
d. separation of Laurentia and Baltica
e. None of the above
4.
What ocean formed as a result of the breakup of Pangea?
a. Pacific
b. Atlantic
c. Indian
d. Arctic
e. Antarctic
The southeast United States is composed of rocks originally from _________.
a. Europe
b. Asia
c. Australia/New Zealand
d. Africa
e. Antarctic
5.
6.
The second stage of the breakup of Pangea involved the separation of
______________.
a. the Atlantic rift northward
b. oceanic tracts between Africa and Antarctica
c. North America from Gondwana
d. Laurentia and Baltica
e. None of the above
7.
The third stage of the breakup of Pangea involved the extension of
______________ to the north to open the Atlantic ocean.
a. rifting
b. suturing
c. subsiding
d. uplifting
e. None of the above
8.
The fourth stage of the breakup of Pangea involved the separation of
______________.
a. the Atlantic rift northward
b. oceanic tracts between Africa and Antarctica
c. North America from Gondwana
d. Laurentia and Baltica
e. None of the above
9.
The dominant type of faulting during the late Triassic along the North American
east coast was __________________.
a. normal
b. subnormal
c. reverse
d. upward
e. thrusting
10.
What is the name of the Late Triassic sediments that filled fault control basins
along the North American east coast?
a. Newark Super Group
b. Ripley Formation
c. Franciscan Formation
d. Shinarump Conglomerate
e. Carmel Formation
What is the dominant lava composition associated with the breakup of Pangea?
a. chalk
b. rhyolite
c. andesite
d. basalt
e. conglomerate
11.
12.
Starting in the Late Triassic, the Gulf of Mexico was a site of ____________?
a. orogenic event
b. glaciation
c. stream deposits
d. lake deposits
e. thick evaporate accumulations
13.
The Louann Salt produce salt domes because _______________.
a. salt flow plastically in the direction of high pressure
b. salt flow plastically in the direction of low pressure
c. salt flow non plastically in the direction of low pressure
d. salt flow non plastically in the direction of high pressure
e. None of the above
.
14.
The eastern United States began subsiding during the Cretaceous Period. The
resulting sediment wedge ___________________.
a. thickened towards the mountains
b. thins towards the seaward
c. thickened seaward
d. that is uniform in thickness
e. None of the above
15.
Cretaceous reefs were dominated by which of the following?
a. Basalt
b. Rhyolite
c. Batholiths
d. Rudistids
e. Coccoliths
16.
The late Cretaceous seas produce large volumes of chalk which is made out of
_______________.
a. basalt
b. rhyolite
c. batholiths
d. rudistids
e. coccoliths
17.
The intensity of tectonic activity along the Cordillera was linked to
_________________.
a. the sea floor spreading rate in the Atlantic ocean
b. the sea floor spreading rate in the Panthalassa ocean
c. the rate of the mountain building
d. isostatic rebound
e. None of the above
18.
During the Mesozoic Era as much as ______ percent of the cordillera region was
added to North America.
a. 50
b. 25
c. 10
d. 95
e. 70
19.
What is the term for when a plate fragment rides up and over another plate?
a. obduction
b. subduction
c. adduction
d. conduction
e. acceleration
20.
Accretionary tectonics involves the formation of continents by the addition of
______________.
a. batholiths
b. chalk
c. unconformity
d. strata
e. exotic terranes
21.
Which of the following is not a Mesozoic Cordillera orogenic event?
a. Sevier.
b. Sonoma.
c. Nevadan.
d. Laramide
e. Teconic
22.
Triassic rocks of the Cordillera started out marine and ended as continental with
a __________________ separating them.
a. batholiths
b. chalk
c. unconformity
d. strata
e. exotic terranes
23.
The Chinle Formation was deposited by _____________.
a. streams and lakes
b. wind
c. ocean currents
d. turbidites
e. None of the above
24.
In what direction did the deformation shift in the Cordillera during the Mesozoic?
a. Northward
b. Eastward
c. Southward
d. Westward
e. Southwest
25.
Sediment deposited between converging plates creates a sequence of rocks
called ______________.
a. an exotic terrane
b. a mélange
c. ophiolites
d. rudistid reefs
e. batholiths
26.
During the Mesozoic Era the Cordillera subduction zones produced vast
quantities of magma which lead to the formation of ____________________.
a. batholiths
b. rhyolite
c. andesite
d. rudistids
e. coccoliths
27.
The Sevier orogeny is characterized by ______________________.
a. multiple overlapping thrust blocks
b. shield volcanoes
c. tensional faulting
d. subduction zones
e. exotic terranes
28.
The Laramide orogeny principally impacted the region of today’s ___________.
a. Canadian shield
b. Southern States
c. Rocky Mountain States
d. Northeastern States
e. Midwest
29.
The paleo depositional environment for the Navajo Sandstone is
_____________.
a. glacial ice
b. eolian
c. coastal dunes
d. desert dunes
e. the Grand Canyon
30.
Regression of the Sundance Sea was followed by the dinosaur rich deposits of
the ________________________.
a. Chinle Formation
b. Sundance Formation
c. Navajo Sandstone
d. Morrison Formation
e. Shinarump Conglomerate
31.
Epicontinental seas of the __________________ period were the most extensive
of the Mesozoic.
a. Cenozoic
b. Triassic
c. Cretaceous
d. Jurassic
e. Archean
32.
During the Cretaceous period extensive accumulations of sediments were
deposition in the Cordillera region in _____________________.
a. rift basins
b. foreland basins
c. back-arc basins
d. foreign basins
e. exotic basins
33.
As the Cretaceous period sea transgressed onto the Cordillera, what unit was
deposited?
a. Dakota Group
b. Newark Group
c. Morrison Formation
d. Niobrara Formation
e. Deccan Traps
34.
Rocks that compose the Alpine-Himalayan mountain belt were derived from
sediments deposited in the _________________.
a. Tethys Sea
b. Gulf of Mexico
c. South Atlantic Ocean
d. Pacific Ocean
e. Sundance Sea
35.
Folding and faulting of Tethys sea sediments resulted from ________________.
a. Australia moving northward into New Zealand
b. Africa moving northward into Europe
c. Europe moving eastward into North America
d. Asia moving southward into Antarctica
e. None of the above
36.
South American and Africa rifting started in the Jurassic period. What did the
newly developing South Atlantic look like?
a. A broad seaway
b. A nearly circular seaway
c. The shape of the modern Pacific ocean
d. The shape of the modern South Atlantic
e. The shape of the modern Red Sea
37.
Subduction began on the western margin of South America leading to volcanism
of ________________composition.
a. basalt
b. rhyolite
c. andesite
d. chalk
e. granitic
38.
The Karoo basin is known for _____________fossils
a. mammal-like vertebrate
b. fish-like vertebrate
c. mollusk
d. turtle
e. trilobite
39.
Of all the continental fragments produced by the breakup of Pangea which one
travel the greatest distance since the Mesozoic?
a. North America
b. Europe
c. Africa
d. Australia/New Zealand
e. India
40.
What are the Deccan Traps?
a. Vast reef structures
b. Immense sedimentary wedge
c. Mélanges
d. Large quantities of low-viscosity basaltic lava
e. A long narrow sea way
Answers to Questions
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
b
e
c
b
d
b
a
d
a
a
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
d
e
b
c
d
e
a
e
a
e
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
e
c
a
b
b
a
a
c
b
d
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
c
c
a
a
b
e
c
a
e
d
MULTIPLE-CHOICE QUESTIONS
1.
During Mesozoic, the westward motion of the North American continent was a result of the
a. opening of the Iapetus sea.
c. opening of the Pacific Ocean.
b. opening of the Tethys Sea.
d. opening of the Atlantic Ocean.
2.
What was the geologic period during which the Sundance Sea occupied a large region of the
western United States?
a. Carboniferous
c. Jurassic
b. Triassic
d. Cretaceous
3.
The geographic (and geologic) separation between the Triassic faulted sedimentary basins and
crystalline rocks of the east coast of the United States and the flat-lying Cretaceous sediments of
the Atlantic coastal plain is called the
a. Newark Basin.
c. Mississippian Embayment.
b. Fall Line.
d. Palisade Sill.
4.
The shells of these bivalves form the basic framework of many Cretaceous reefs. They have high
porosity and permeability, making their reefs some of the world’s greatest Cretaceous oil reservoirs.
They are termed
a. coccoliths.
c. accretions.
b. rudists.
d. chalk reefs.
5.
Chalk is composed of the shells of what organism?
a. diatoms
c. radiolaria
b. rudists
d. coccoliths
6.
During plate collisions, the process that occurs when low-density rocks (and sediments) from a
subducting oceanic plate are emplaced on the continental plate is called
a. accretion.
c. reduction.
b. obduction.
d. shortening.
7.
During Triassic, and increasing in frequency during Jurassic and Cretaceous, graywackes,
mudstones, cherts, and volcanites that had been swept into the subduction zone were severely
folded, faulted, and metamorphosed. The intensely crumpled and altered rock sequences that
were affected by compression between the plates are appropriately termed
a. mélange.
c. batholiths.
b. decollement.
d. strata.
8.
The Moenkopi, Shinarump, and Chinle formations all formed during what geologic period?
a. Permian
c. Jurassic
b. Triassic
d. Cretaceous
9.
The initial orogenic event that marked the development of the Cordillera region was the
a. Sevier Orogeny.
c. Laramide Orogeny.
b. Nevadan Orogeny.
d. Sonoma Orogeny.
10.
The Nevadan Orogeny that resulted in the intrusions of the granite batholiths that formed the Sierra
Nevada Mountains took place during what geologic period?
a. Triassic
c. Cretaceous
b. Jurassic
d. Permian
11.
During which orogeny were strata sheared from underlying Precambrian rocks and broken along
parallel planes of weakness to form multiple, imbricated, low angle thrust faults?
a. Sevier Orogeny
c. Nevadan Orogeny
b. Sonoma Orogeny
d. Laramide Orogeny
12.
Cretaceous rocks of Wyoming and Colorado contain rocks composed of clay minerals formed by
the alteration of volcanic ash. These clayey rocks are called
a. bentonites.
c. molasses.
b. flysch.
d. mélanges.
13.
Besides the extensive mountain-building events of Late Cretaceous, this period of geologic time is
also noted for
a. widespread marine regressions.
c. widespread glaciation.
b. widespread marine transgressions.
d. increase in global temperatures.
14.
What Cordilleran Orogeny occurred during Cretaceous and was characterized by eastward
directed, low-angle thrust faults?
a. Sonoma
c. Sevier
b. Nevadan
d. Laramide
15.
The flood basalts of the Deccan Plateau (Traps) in India suggest that
a. the Indian continent experienced a failed rifting event.
b. the Indian continent was struck during Late Cretaceous by a meteorite.
c. the Indian continent passed over a “hot spot” on its voyage toward Laurasia.
d. they are the eroded remnants of once extensive volcanoes.
16.
The dismemberment of Pangea occurred in four stages. The first stage occurred during
__________ with rifting and volcanism along normal fault systems.
a. Permian
c. Jurassic
b. Triassic
d. Cretaceous
17.
The second stage in the dismemberment of Pangea involved the opening of narrow oceanic tracts
between southern Africa and _____________.
a. Europe
b. North America
c. South America
d. Antartica
e. Asia
18.
The final stage in the breakup of Pangea occurred during Early Cenozoic and took an estimated
______________ years for complete Pangea fragmentation.
a. 25 million
d. 100 million
b. 45 million
e. 150 million
c. 65 million
19.
The orogenic event of the Cordilleran region occurred at or near the Permian-Triassic boundary
when an eastward-moving volcanic arc collided with the North American Pacific margin is called the
a. Laramide Orogeny.
d. Nevadan Orogeny.
b. Seiver Orogeny.
e. Acadian Orogeny.
c. Sonoma Orogeny.
20.
This organic event shifted eastward to the Cratonic region where today’s Rocky Mountains of New
Mexico, Colorado, and Wyoming are located. The move-eastward disturbances constitutes the
a. Laramide Orogeny.
d. Nevadan Orogeny.
b. Seiver Orogeny.
e. Acadian Orogeny.
c. Sonoma Orogeny.
FILL IN THE BLANK
1.
The orogeny that occurred when an eastward-moving volcanic arc collided with the Pacific margin
of North America during Permian-Triassic is called the
.
2.
The geologic features that extend from Cretaceous into Cenozoic and mark the passage of India
across a fixed hot spot in the mantle is
3.
In contrast to subduction, the process that occurs when one rock mass rides up and over another is
called
.
4.
The Laramide Orogeny at the end of Cretaceous resulted in the formation of what range?
5.
The orogenic event that marked the formation of low-angle detached thrust faults and which
resulted in over 100 kilometers of crustal shortening in the Nevada Utah area is called
.
6.
The formation that is well known for the presence of Jurassic terrestrial reptiles and dinosaurs and
that strongly suggests that the fossils of this formation were terrestrial in origin is
.
7.
The Cretaceous formation that has yielded the remains of a variety of marine creatures, a large
Cretaceous diving bird, marine reptiles and the large flying reptile Pteranodon is called
.
8.
The basin at the southern end of Africa that formed during Late Carboniferous but is known for its
wealth of fossilized mammal-like reptiles is called
.
9.
The
.
Painted
Desert
of
Arizona
is
developed
mostly
with
what
formation?
10.
Chalk is composed of the shells of what organism?
11.
The growth of a continent by progressive incorporation of crustal fragments and exotic terranes is
called ______________ __________________.
12.
The crumpled, altered rock sequences that are trapped between converging plates are called a
______________.
13.
In plate tectonic terms, the depositional basin that received terrigenous clastics supplied by streams
from the Cordilleran highlands is called a ______________ _____________.
14.
In geology, an analogous region of displaced terranes is called a ____________ _____________.
15.
During Cretaceous, invertebrates called ________________ contributed their skeletal substance to
reefs.
TRUE-FALSE
1.
Evaporative conditions were prevalent in the Gulf Coast region during Late Triassic and
Jurassic, resulting in the deposition of thick layers of salt that contributed to the formation
of salt domes.
2.
The supercontinent of Pangea first started to rift apart during Early Jurassic.
3.
The rifting of a supercontinent such as Pangea is often signaled by outpourings of lava
and other volcanic activity.
4.
Obduction occurs when high-density rock material is stripped off and emplaced on lowdensity rock material during continent-continent plate collisions.
5.
Most of the structures of the present-day Rocky Mountains are a result of the Sevier
Orogeny.
6.
The Deccan Plateau (also called the Deccan Traps) may record the passage of a drifting
India over a “hot spot” in the mantle.
7.
The poor sorting and high content of unweathered rock and mineral fragments suggests
that the sediments of the Newark Group were transported only a short distance from the
source of the sediments.
8.
The upward motion of the salt from evaporite layers in the Gulf Coast deforms and
fractures the overlying rock, providing structural traps for petroleum and natural gas.
9.
The Jurassic Morrison Formation has provided excellent fossil remains of many large
marine reptiles.
10.
The sequence of formations that are exposed in the walls of Zion Canyon in southern
Utah is upper Triassic: Chinle Group, Moenkopi, Shinarump, followed by Lower Jurassic
Navajo sandstone, Wingate sandstone, Kayenta Formation.
ANSWER KEY
Multiple Choice
1. d
2. c
3. b
4. b
5. d
6. b
7. a
8. b
9. d
10. b
11. a
12. a
13. b
14. c
15. c
16. b
17. d
18. e
19. d
20. d
Fill Ins
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Sonoma Orogeny
Deccan Traps
Obduction
Rocky Mountains
Sevier Orogeny
Morrison Formation
Niobrara Formation
Karoo basin
Chinle Formation
Coccoliths
accretionary tectonics
mélange
foreland basin
tectonic collage
rudistids
True/False
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
T
F
T
F
F
T
T
T
F
F
RESPONSES TO QUESTIONS ACCOMPANYING SELECTED FIGURES
FIGURE 13–2 (p. 388) Faulting along the eastern margin of North America was a consequence of
the separation of North America from the Moroccan region of northwestern Africa.
FIGURE 13–7 (p. 391) Examination of the map should reveal whether the location of your college
was on land, beneath a shallow sea, or in the open ocean.
FIGURE 13–10 (p. 393) The fault is a normal or tensional fault, such as would be expected along
the trailing passive margin of a tectonic plate.
FIGURE 13–22 (p. 401) An ophiolite suite would have been developed just east of the trench.
CHAPTER 13—MESOZOIC EVENTS
Multiple Choice Questions
1. The Mesozoic was characterized by the:
a. assembly of continents into Pangea.
b. breakup of Pangea.
c. stable positions of continents.
d. assembly of continents into Gondwana.
e. breakup of Gondwana.
Ans: b
Feedback: See pages 386-387
2. These types of sediments were deposited during Late Triassic and Early Jurassic of eastern
North America:
a. turbidites and submarine fan deposits.
b. nonmarine red sandstones and shales.
c. shallow water carbonate rocks.
d. barrier island and beach sands.
e. reef carbonates and associated evaporates.
Ans: b
Feedback: See page 387
3. Where is the basaltic Palisades sill is located?
a. Pacific northwestern U.S.
b. western Texas and New Mexico area
c. New York and New Jersey area
d. Michigan basin
e. northern India
Ans: c
Feedback: See page 387
4. Where were thick Jurassic evaporite deposits, which formed salt domes, deposited in North
America?
a. Michigan basin
b. west Texas and New Mexico area
c. Gulf of Mexico area
d. Great Salt Lake area
e. western New York
Ans: c
Feedback: See page 388
5. During what Mesozoic time interval were the Atlantic and Gulf coastal plain areas covered by
the sea?
a. Early Triassic
b. Late Triassic-Early Jurassic
c. Early-Middle Jurassic
d. Late Jurassic
e. Cretaceous
Ans: e
Feedback: See pages 389-390
6. This type of organism was an important contributor to Cretaceous reefs:
a. rugose corals.
b. tabulate corals.
c. stromatolites.
d. rudistids.
e. sponges.
Ans: d
Feedback: See page 390
7. The Cretaceous is named for what rock type, a variety of limestone deposited in inland seas in
many parts of the world?
a. micrite
b. claystone
c. chalk
d. coal
e. reef rock
Ans: c
Feedback: See page 390
8. What Cretaceous unit listed below has yielded the remains of a variety of marine creatures
including a diving bird, marine reptiles, and flying reptiles?
a. Newark Supergroup
b. Dakota Group
c. Niobrara Formation
d. Navajo Sandstone
e. Morrison Formation
Ans: c
Feedback: See page 406
9. Most of the structures of the present-day Rocky Mountains are the result of what orogeny?
a. Sevier
b. Antler
c. Laramide
d. Sonoma
e. Nevadan
Ans: c
Feedback: See pages 397-399
10. The rocks exposed in the Painted Desert and Petrified Forest National Park, Arizona are:
a. Moenkopi and Shinarump Formations.
b. Chinle Formation.
c. Navajo Sandstone and Wingate Sandstone.
d. Kayenta Formation.
e. Niobrara Formation.
Ans: c
Feedback: See pages 394-395
11. The cross-bedded formations exposed in the walls of Zion National Park in Utah belong to
what formation?
a. Moenkopi Formation
b. Niobrara Formation
c. Navajo Sandstone
d. Kayenta Formation
e. Chinle Formation
Ans: c
Feedback: See pages 399 and 403
12. The bones of more than 70 species of dinosaurs are present in floodplain deposits, exposed
near Grand Junction, Colorado. What is the formation?
a. Moenkopi Formation
b. Kayenta Formation
c. Navajo Sandstone
d. Morrison Formation
e. Chinle Formation
Ans: d
Feedback: See page 400
13. At what time during Mesozoic was the interior of North America was flooded by an
epicontinental sea?
a. Jurassic
b. Triassic
c. Cretaceous
d. Permian
e. Pliocene
Ans: c
Feedback: See pages 400-403
14. What Mesozoic orogeny occurred east of the Sierra Nevada Mountains and caused multiple
overlapping, low angle thrust faults that were thrust eastward?
a. Antler
b. Sevier
c. Laramide
d. Sonoma
e. Nevadan
Ans: b
Feedback: See pages 396-397
15. What orogeny was associated with the formation of a mélange (the Franciscan fold belt of
California) and the generation of enormous volumes of granitic rock associated with a subduction
zone (the Sierra Nevada, Idaho, Baja California, and Coast Range batholiths)?
a. Sevier
b. Antler
c. Laramide
d. Sonoma
e. Nevadan
Ans: e
Feedback: See pages 395 and 400