Deck 10: Early Paleozoic Earth History

Question 1

The Transcontinental Arch and portions of the Canadian shield were above sea level during the Sauk transgression.

Answer 1

True

Question 2

The Cordilleran mobile belt formed on what is now the east coast of North America.

Answer 2

False

Question 3

Glaciation and tectonic events were the likely causes for transgressions and regressions during the Paleozoic.

Answer 3

True

Question 4

The four Paleozoic cratonic sequences, in order from oldest to youngest, are Tippecanoe, Sauk, Kaskaskia, and Zuni.

Question 5

Thick salt deposits have been explained by evaporation in silled (also called "barrier") basins.

Question 6

Africa, Antarctica, and Australia were once part of Gondwana.

Question 7

Rise and fall of sea level in epeiric seas can be partly explained by continental glacial events.

Question 8

During the Cambrian, most of Earth's land was located in the southern hemisphere.

Question 9

During the Paleozoic Era, cratons were covered with large bodies of water called epeiric seas.

Question 10

The eastern margin of North America has always been a passive continental margin.

Question 11

Orogenesis occurs along mobile belts.

Question 12

Mobile belts commonly are associated with convergent plate margins.

Question 13

During a transgressive sequence, sedimentary facies migrate toward the ocean.

Question 14

By the beginning of the Paleozoic Era, six of the seven continents were present.

Question 15

William Smith created the world's first geologic map.

Question 16

The Cambrian sedimentary deposits of the Grand Canyon represent a regressive sequence.

Question 17

Shields are the exposed portions of cratons that contain igneous and metamorphic rocks.

Question 18

Geologic periods are divided based on the chronology of one complete transgressive-regressive cycle.

Question 19

The Cordilleran mobile belt marks the boundary between the United States and Canada.

Question 20

Reconstruction of Paleozoic paleogeography is well documented by magnetic stripe data from rocks 600 to 250 million years old on the ocean floor.

Question 21

During the early Paleozoic, sea levels were higher than they are today.

Question 22

What was the first orogeny to affect the Appalachian mobile belt?

A) Acadian
B) Taconic
C) Cordilleran
D) Alpine
E) Caledonian

Question 23

The first major Paleozoic transgression onto the North American craton was the ____ sequence.

A) Tippecanoe
B) Kaskaskia
C) Sauk
D) Taconic
E) Appalachian

Question 24

Limestone structures constructed in the marine environment by some skeletal material of living organisms are ____.

A) evaporites
B) clastic wedges
C) mobile belts
D) ophiolites
E) organic reefs

Question 25

The stable nucleus of a continent consisting of a Precambrian shield and a platform of buried ancient rocks is a(n) ____.

A) craton
B) benthos
C) mobile belt
D) orogenic belt
E) basin

Question 26

The ____ Ocean opened along a ____ plate boundary between Laurentia and Baltica.

A) Atlantic, divergent
B) Iapetus; convergent
C) Atlantic; convergent
D) Iapetus; divergent
E) Iapetus; transform

Question 27

Why are Mesozoic and Cenozoic paleogeographic reconstructions more accurate than reconstructions for earlier time intervals?

A) Mesozoic and Cenozoic rocks are better preserved on ocean floor
B) Mesozoic and Cenozoic rocks have not been destroyed by subduction
C) Mesozoic and Cenozoic rocks were deposited underwater.
D) Mesozoic and Cenozoic rocks have not experienced erosion.
E) Very few tectonic events have occurred since Mesozoic and Cenozoic time.

Question 28

Thick sections of evaporite deposits that were formed in basins surrounded by large reef complexes are common in the Tippecanoe sequence.

Question 29

A succession of rocks bounded by unconformities is a(n) ____.

A) period
B) cratonic sequence
C) system
D) bedding plane
E) ecosystem

Question 30

What two sequences were deposited in the early Paleozoic?

A) Taconic and Tippecanoe
B) Sauk and Tippecanoe
C) Taconic and Acadian
D) Zuni and Kaskaskia
E) Zuni and Acadian

Question 31

Conical marine organisms that lived during the Cambrian and were the earliest builders of reef-like structures are known as ____.

A) protists
B) cyanobacteria
C) brachiopods
D) sponges (porifera)
E) archaeocyathids

Question 32

The Taconic orogeny was the last of the major mountain building events in the Appalachians.

Question 33

The Grand Canyon formed due to ____.

A) erosion
B) Rifting
C) a divergent plate boundary
D) fault block basin development
E) lateral accretion

Question 34

Long linear limestone masses composed of skeletal material and forming a barrier between a shallow platform on one side and a comparatively deep marine basin on the other side are ____.

A) barrier islands
B) ophiolites
C) barrier reefs
D) Beaches
E) alluvial fans

Question 35

Silled basins are thought to be the site of deposition of thick ____ deposits.

A) fossil
B) evaporite
C) clastic
D) metamorphic
E) ash

Question 36

Relatively stable, immobile parts of continents that form the foundation on which Phanerozoic sediments were deposited are ____.

A) cratons
B) mobile belts
C) orogens
D) clastic wedges
E) back-arc basins

Question 37

Clastic wedges can be identified by ____.

A) their associated evaporite deposits
B) underwater volcanism
C) the gradation of sediments from thick and coarse to thin and fine
D) their fossil content
E) a homogenous thickness of sediments

Question 38

A(n) ____ is an accumulation of detrital sediment adjacent to an uplifted area.

A) clastic wedge
B) organic reef
C) c raton
D) orogenic belt
E) mobile belt

Question 39

A clastic wedge is a wedge-shaped block of sedimentary rocks bounded by faults that intersect at an acute angle.

Question 40

The earliest organic reefs are known from the Ordovician Period.

Question 41

A(n) ____________________ ____________________ is an elongated area of mountain building located along the margins of continents where sediments are deposited in the relatively shallow waters of the continental shelf and the deeper waters at the base of the continental slope.

Question 42

The first major transgression onto the North American continent is recorded in rocks of the ____________________ Sequence.

Question 43

A cratonic ____________________ is a succession of rocks bounded by unconformities.

Question 44

Erosion of the Taconic Highlands resulted in the development of a(n) ____________________ called the ____________________.

Question 45

_____________________ ___________________ is an important tool in geology because it allows geologists to subdivide sedimentary rocks into related units that are bounded by time-stratigraphically significant boundaries.

Question 46

The early Paleozoic history of continents involves ____.

A) widespread glaciation
B) stable plate positions
C) mountain building and marine transitions/regression.
D) extensive volcanism
E) subduction and emplacement of batholiths

Question 47

Each of the major continents at the beginning of the Paleozoic can be divided into two major components, a(n) ____.

A) trough and a range
B) craton and a mobile belt
C) immobile belt and a rift margin
D) craton and an ocean basin
E) immobile belt and a mobile belt

Question 48

A(n) ____________________ ____________________ is a limestone structure constructed by living organisms, some of which contribute skeletal materials to the reef framework.

Question 49

What is a broad shallow sea that covers part of a continent?

A) magma ocean
B) cumulus
C) epeiric (epicontinental) sea
D) labyrinthodont
E) archaeocyathid

Question 50

The presence of a reef indicates which kind of past environment?

A) cool, shallow sea
B) warm, shallow sea
C) cool, deep sea
D) warm, deep sea
E) cool, lagoon

Question 51

Widespread, shallow seas that transgress over a craton are called ____________________.

Question 52

Sequence boundaries are bounded by ____ and formed during ____.

A) unconformities; a sea level rise
B) unconformities; a sea level drop
C) unconformities; transgressions
D) faults; subduction
E) faults; divergence

Question 53

A cratonic sequence is ____.

A) localized
B) short-lived
C) large-scale
D) determined by the fossil content of a craton
E) when cratonic rocks are ordered via numerical dating

Question 54

What happened to the mountains formed during the Taconic orogeny?

A) They were buried under volcanic ash.
B) They were subducted when the Iapetus ocean opened.
C) They were subducted during the closure of the Iapetus ocean.
D) They were eroded into the Queenston Delta.
E) They were isostatically uplifted.

Question 55

Which eon directly follows the Precambrian?

A) Paleozoic
B) Cambrian
C) Hadean
D) Phanerozoic
E) Proterozoic

Question 56

The ____________________ orogeny in Europe is a mirror image of the Taconic and Acadian orogenies in North America.

Question 57

A series of large, northeast-southwest trending islands that protruded from the Sauk Sea were known as the ____________________ ____________________.

Question 58

A transgression is represented in the rock record, from bottom to top (oldest to youngest), by ____.

A) shale, sandstone, and limestone
B) limestone, sandstone, and shale
C) sandstone, shale, and limestone
D) sandstone, limestone, and shale
E) limestone, shale, and sandstone

Question 59

During the early Paleozoic, North America was located near the ____.

A) North Pole
B) in its present day location
C) paleo equator
D) South Pole
E) mid-Southern latitudes

Question 60

In which Paleozoic continent was most of present-day North America located? ____________________.

Question 61

Discuss the silled (barrier) basin model for evaporite deposition. What features of evaporites does this model explain?

Question 62

Why are the regressive phases of cratonic sequences marked by unconformities?

Question 63

Discuss the stratigraphy of the Tippecanoe Sequence. What types of rocks are found in this sequence?

Question 64

Discuss the paleogeography of the Early Paleozoic. How did this paleogeography differ from present-day geography?

Question 65

Compare and contrast cratons and mobile belts. What types of rocks are they composed of and what are the relative ages of these rocks? Provide specific examples of cratons and mobile belts.

Question 66

Discuss the Early Paleozoic development of sedimentary rocks in North America.

Question 67

Discuss the major Early Paleozoic transgressions and regressions in North America. How did these transgressions and regressions shape the geologic character of North America today? Give examples of specific features caused by these transgressions and regressions.

Question 68

Discuss the publication of the world's first geologic map. Who published it? What area did it cover? What was the purpose of this map?

Question 69

Discuss the stratigraphy of the Grand Canyon. What does this stratigraphy imply about sea level? What are the formation names of the Grand Canyon rocks?

Question 70

Describe and discuss the stratigraphy of the Grand Canyon. What does this stratigraphy illustrate? Identify the formations in the Grand Canyon and discuss their relationships.