Deck 6: Pages of Earth S Past: Sedimentary Rocks

Question 1

Precipitation of gypsum due to evaporation of seawater produces which kind of sedimentary rock?

A)biochemical
B)chemical
C)clastic
D)organic

Answer 1

B

Question 2

Diagenesis refers to ________.

A)the development of layering within sedimentary rocks
B)the act of deposition of sediment that will ultimately form sedimentary rock
C)physical and chemical alterations,including compaction and cementation,that occur as sediment is transformed into rock
D)the natural process of separating sediment by grain size

Answer 2

C

Question 3

The breakdown of exposed rock into small fragments and dissolved ions is termed ________.

A)deposition
B)erosion
C)weathering
D)lithification

Answer 3

C

Question 4

Cementation of sediments occurs when minerals ________ the spaces between sediment grains.

A)swell into
B)pass through
C)precipitate in
D)dissolve in

Question 5

What type of sediment is typically found in lake bottoms?

A)gravel
B)sand
C)pebbles
D)clay/mud

Question 6

Compaction and cementation of grains occur during ________.

A)erosion
B)lithification
C)transport
D)weathering

Question 7

If water is the transport mechanism of sediment,the grain size of sedimentary deposits most closely indicates the ________.

A)geographic extent of the weathering source rock at outcrop
B)average velocity of the water from the time of erosion until deposition
C)velocity of the water at the moment the sediment settled to the bottom
D)climate conditions at the time of deposition

Question 8

Which of the following processes involves the creation of ions in solution?

A)deposition
B)transportation
C)erosion
D)weathering

Question 9

The removal of detritus from weathered rock at an outcrop is termed ________.

A)deposition
B)erosion
C)weathering
D)lithification

Question 10

If a geologist found preserved mud cracks,he or she could conclude that the environment in which they formed ________.

A)was once covered in wet mud
B)was once covered by a glacier
C)has been subjected to a major climate change event
D)was the site of a mass extinction event

Question 11

Geologists call individual layers of sedimentary rocks ________,whereas several of them together are called ________.

A)beds;strata
B)strata;beds
C)laminations;graded beds
D)graded beds;laminations

Question 12

The elevation of a mountain is slowly decreased by weathering and ________.

A)lithification
B)sedimentation
C)erosion
D)deposition

Question 13

Consult the figure below.Here,distinct internal laminations are inclined at an angle to the boundary of the main sedimentary layers.This is termed ________.

A)graded beds
B)cross beds
C)horizontal beds
D)tilted beds

Question 14

Topset,foreset,and bottomset beds together are indicative of ________ environments.

A)alluvial fan
B)lake bottom
C)delta
D)deep-marine

Question 15

A gravel bar in a river is an example of a landform created by ________.

A)deposition
B)erosion
C)transportation
D)lithification

Question 16

Glacial till is composed of ________-sized particles.

A)mud
B)sand
C)boulder
D)all

Question 17

Lithification occurs ________.

A)in the shallow subsurface
B)at the surface of Earth
C)deep under the ground
D)high in the mountains

Question 18

Grains become rounded primarily during ________.

A)weathering at the outcrop
B)lithification
C)transportation
D)deposition

Question 19

As compared with metamorphism,diagenesis ________.

A)means exactly the same thing
B)takes place at lower temperatures and pressures
C)takes place at higher temperatures and pressures
D)takes place at greater depths that are well within the mantle

Question 20

Lithification,the process by which sediments are turned into sedimentary rocks,includes ________.

A)erosion and transportation
B)transportation and cementation
C)erosion and deposition
D)compaction and cementation

Question 21

What is the difference between the formations of chalk versus chert?

A)They have different grain sizes.
B)They are made of different source materials.
C)Chalk is terrestrial;chert is marine.
D)Chalk is biochemical;chert is chemical.

Question 22

Which of the following is FALSE? As compared to arkose,quartz sandstone ________.

A)contains more angular grains
B)does not contain significant amounts of feldspar
C)is likely to be found farther away from weathering granitic source rock
D)is considered to be more compositionally mature

Question 23

Cemented shells of marine organisms form which kind of sedimentary rock?

A)biochemical
B)chemical
C)clastic
D)organic

Question 24

A fine-grained clastic sedimentary rock that splits into thin sheets is ________.

A)mudstone
B)shale
C)sandstone
D)arkose

Question 25

Two major sources of energy,coal and oil shale,are considered ________ sedimentary rocks.

A)clastic
B)biochemical
C)organic
D)chemical

Question 26

Lake deposits tend to be composed of finely laminated mudstones,indicative of ________.

A)quiet water
B)oscillating waves
C)bioturbation
D)current flow

Question 27

Scour marks are an indicator of ________.

A)submarine landslides
B)quiet,still water
C)arid environments
D)current flow

Question 28

Large layers of cross-bedded sand can be indicative of a ________ environment.

A)submarine
B)beach
C)desert
D)fluvial

Question 29

The primary difference between breccia and conglomerate is that conglomerate ________.

A)is finer grained than breccia
B)is coarser grained than breccia
C)possesses more angular grains than breccia
D)possesses more rounded grains than breccia

Question 30

Lithified detritus (breakdown products of preexisting rocks)forms which kind of sedimentary rock?

A)biochemical
B)chemical
C)clastic
D)organic

Question 31

A well-sorted sandstone with asymmetric ripples was most likely deposited as sand by a(n)________.

A)river (far from source)
B)glacier
C)river (near source)
D)alluvial fan

Question 32

The image below shows an outcrop of coarse-grained sedimentary rock.Note the rock hammer for scale.What is the name of this rock type?

A)sandstone
B)shale
C)breccia
D)conglomerate

Question 33

Which of the following does NOT reflect transport distance?

A)angularity
B)type of cement
C)sphericity
D)mineral content

Question 34

When limestone becomes chemically altered so that half of the calcium atoms are replaced by magnesium,the resultant rock is termed ________.

A)agate
B)dolostone
C)jasper
D)travertine

Question 35

The majority of the rocks that are formed at the surface of Earth are ________ rocks.

A)intrusive igneous
B)extrusive igneous
C)sedimentary
D)metamorphic

Question 36

Siltstone or mudstone containing marine fossils likely formed in a ________ environment.

A)shallow-marine
B)deep-marine
C)marine-delta
D)coastal-beach

Question 37

Biochemical limestones are dominated by carbonate mud and fragments of ________.

A)siliceous shells of planktonic diatoms and foraminifera
B)skeletons of marine invertebrates made of calcite and aragonite
C)the phosphatic bones of fish
D)the organic breakdown products of wood and leaves from trees

Question 38

The image below shows a series of graded beds.How many full sets of graded beds are shown?

A)1
B)3
C)12
D)15

Question 39

Clastic sedimentary rocks are primarily classified on the basis of ________.

A)grain size
B)degree of sorting
C)angularity
D)mineral composition

Question 40

Because the velocity of sediment settling (deposition)is positively related to grain size for waterborne sediments,fluvial deposits are more likely than glacial deposits to ________.

A)be well sorted
B)include coarse grains,such as cobbles
C)include fine grains,such as clay
D)have angular grains

Question 41

Shallow-marine deposits tend to have abundant fossils due to their proximity to ________.

A)reefs
B)beaches
C)deltas
D)rivers

Question 42

Which of the following is FALSE about regressions?

A)They are not typically well preserved in the sedimentary record.
B)They can occur when the climate warms and continental ice sheets melt.
C)They occur when the land is uplifted by tectonic processes.
D)Coastal environments will migrate seaward.

Question 43

Sea level rises locally,and marine sediments are deposited on top of terrestrial sediments during events termed ________.

A)transgressions
B)regressions
C)turbidity currents
D)cross bedding

Question 44

Thick accumulations of sediments and fossils in the deep ocean tend to be ________-sized due to the low amounts of energy.

A)cobble
B)gravel
C)clay
D)sand

Question 45

Basins that form on the continental side of mountain ranges are called ________ basins.

A)rift
B)passive-margin
C)foreland
D)intracontinental

Question 46

Limestone can be either a biochemical or a chemical sedimentary rock.Explain how both types of limestone are formed.Make sure to describe the environments in which they were formed.

Question 47

Describe the difference between lithification and diagenesis.

Question 48

Sedimentary basins are often subject to ________,which allows them to fill with thick accumulations of sediments.

A)erosion
B)diagenesis
C)uplift
D)subsidence

Question 49

In which of the following three basin types might you be able to find oil forming and why? Rift basin,passive-margin basin,and foreland basin.

Question 50

________ basins contain the largest accumulation of marine sediments.

A)Rift
B)Passive-margin
C)Foreland
D)Intracontinental

Question 51

The image below shows a layer of ________,which is an accumulation of dead plant material.

A)limestone
B)coal
C)sandstone
D)chalk

Question 52

Describe the depositional environment that formed the layers shown in the image below.

Question 53

Beach sediments travel ________ the ocean during a transgression and ________ the ocean during a regression.

A)toward;away from
B)away from;toward
C)parallel to;perpendicular to
D)perpendicular to;parallel to

Question 54

If a geologist finds thick accumulations of fossiliferous limestone,in what type of basin might they have been formed?

A)passive-margin
B)intracontinental
C)rift
D)foreland

Question 55

What traits would a clastic sedimentary rock have if it had traveled far from its source and was carried in a current with uniform energy? What environment would this be?