Deck 12: Tectonics, Earthquakes, and Volcanism

Question 1

The average elevation of exposed land is

A)-2070 m.
B)100 m.
C)875 m.
D)8848 m.
E)10753 m.

Answer 1

C

Question 2

A hypsographic curveis

A)a graph that shows the change in temperature with depth below the surface of a continent.
B)a graph that shows the change in temperature with depth below the surface of the ocean floor.
C)a generalized curve showing Earth's surface by area and elevation in relation to sea level.
D)a graph that shows Earth is of relatively high relief.
E)a graph that shows Earth's relief is great when compared to its diameter.

Answer 2

a generalized curve showing Earth's surface by area and elevation in relation to sea level.

Question 3

The undulating form that gives Earth's surface its character and general configuration is called

A)relief.
B)an order of relief.
C)topography.
D)crust.
E)tectonics.

Answer 3

C

Question 4

The concept of "orders of relief" refers to

A)the ordering of surface features based on height.
B)the ordering of surface features based on their time of origin.
C)the scale of features.
D)the rate at which stress is relieved in the crust.
E)the rate at which the landscape evolves.

Question 5

A topographic region that is characterized by local relief of more than 100 m,but less than 600 m,is considered a

A)plain.
B)high tableland.
C)hill or low tableland.
D)mountain.
E)plateau

Question 6

Scientific evidence regarding the nature of faulting and crustal movement in California suggests

A)that a number of small earthquakes may preceed a major earthquake.
B)that there is no warning sign of an impending large earthquake.
C)that a portion of southern California is poised to break from the mainland and fall into the ocean.
D)that a new mountain chain is developing along the fault system.
E)that humans do not know enough about earthquakes to properly plan large cities in this region.

Question 7

The nucleus of old crystalline rock in each of the principal continental masses is called a

A)basalt mass.
B)continental shield,or craton.
C)mountain mass.
D)composite zone.
E)pliton.

Question 8

Divisions among topographic regions are based on

A)arbitrary criteria regarding height or other descriptive criteria that are in common use.
B)complex statistical analyses of surface relief variation across the surface of Earth.
C)local criteria that have never been universally recognized.
D)logarithmic relationships applied to elevation.
E)a boundary measured by use of global positioning system and analysed in a geographic information system.

Question 9

The average elevation of all of Earth's solid surface is

A)-3800 m.
B)-2070 m.
C)100 m.
D)875 m.
E)8848 m.

Question 10

Which of the following is an example of a third order of relief?

A)the Alps
B)a continental platform
C)the Ottawa Valley
D)the Basin and Range Province
E)the southern ocean

Question 11

Compared to oceanic crust,continental crust is

A)denser.
B)usually formed with less than 50 percent silica and is rich in iron and magnesium.
C)generally more complex in content and structure.
D)essentially composed of basalt.
E)darker in colour.

Question 12

Which of the following is correct?

A)the highest mountain above sea level has an elevation of 88 048 m.
B)the greatest ocean depth is -1030 m.
C)the ratio of land area to ocean area is approximately 140 to 360 million km (or,1:2.5).
D)mean sea level is at 875 m.
E)the lowest land elevation is 0 m.

Question 13

A topographic region that is characterized by local relief of less than 100 m is considered a

A)plain.
B)high tableland.
C)hill or low tableland.
D)depression.
E)prairie

Question 14

Which of the following is an example of a first order of relief?

A)the Alps and Rockies
B)the Tibetan Plateau
C)the Ottawa Valley
D)an ocean basin
E)the prairies

Question 15

Approximately how many square kilometres of Earth's surface is exposed above sea level?

A)18 million
B)29 million
C)49 million
D)149 million
E)360 million

Question 16

If you were paranoid of earthquakes,which of the following areas would be the safest to live?

A)convergent plate boundary
B)divergent plate boundary
C)island arc along a subduction zone
D)shield
E)transform boundary

Question 17

The average elevation of the depth of the oceans is

A)-4526 m.
B)-3800 m.
C)-2070 m.
D)100 m.
E)875 m.

Question 18

Which of the following is an example of a second order of relief?

A)the continental platforms
B)individual mountains and cliffs
C)the Canadian and American Rockies
D)the ocean basins
E)a beach

Question 19

The most detailed order of relief applies to ________ order relief features.

A)first
B)second
C)third

Question 20

Vertical elevation differences in a local landscape are referred to as

A)relief.
B)an order of relief.
C)topography.
D)crust.
E)elevation.

Question 21

Normal faults are associated with

A)tensional forces.
B)compressional forces.
C)plate convergence.
D)transcurrent forces.
E)planing forces.

Question 22

Fault types are defined by

A)the relative motion of the hanging wall and footwall.
B)the amount of movement along the hanging wall and footwall.
C)the amount of energy liberated during movement.
D)the amount of displacement after the movement.
E)the surface pattern resulting from the movement.

Question 23

An exposed footwall with significant vertical extent is known as

A)a fracture zone.
B)an escarpment.
C)dome.
D)anticline.
E)an anticlinal ridge.

Question 24

The text presents a satellite image of the Zagros mountains of Iran as an example of

A)a series of faulted mountain blocks.
B)a zone of tension.
C)a zone of shearing motions.
D)a zone of compression and folding.
E)a zone of shearing and twisting.

Question 25

Which of the following is correctly matched?

A)compression - lengthening or straightening - normal fault
B)tension - shortening or folding - reverse fault
C)shearing - lateral twisting - stike-slip fault

Question 26

Compressional stress along a fault can result in a dropped footwall block relative to the hanging-wall side,producing a

A)reverse fault.
B)lateral fault.
C)normal fault.
D)strike-slip fault.
E)transform fault.

Question 27

Tensional stress along a fault can result in a dropped hanging wall block relative to the footwall side,producing a

A)reverse fault.
B)thrust fault.
C)normal fault.
D)strike-slip fault.
E)transform fault

Question 28

Which of the following represents a surface feature whose relief is opposite that expected based on the fold pattern in the rocks of which it is composed?

A)synclinal valley
B)synclinal ridge
C)inverted anticline
D)synclinal basin
E)fault plane

Question 29

Folded layers of rock can form a wavelike pattern of troughs and crests.The layers near the crest form

A)a syncline.
B)a tension zone.
C)an anticline.
D)a thrust fault.
E)a valley.

Question 30

Domes can be formed by

A)extinct volcanoes.
B)upwarping associated with plate collisions.
C)downwarping associated with plate collisions.
D)upwarping associated with magma movement (i.e. ,plutonic activity).
E)subduction.

Question 31

A brittle rock is likely to respond to stress by ________,whereas a ductile rock is likely to respond by ________.

A)stretching breaking
B)breaking bending
C)isostatically uplifting bending
D)isostatically uplifting breaking
E)shortening fracturing

Question 32

The greatest amount of crustal shortening would be associated with

A)a synclinal ridge.
B)a thrust fault.
C)an overturned anticline.
D)a rift zone.
E)an anticlinal valley.

Question 33

The Wrangellia terranes refer to

A)a former volcanic island arc that migrated 10 000 km to its present location along the western margin of North America.
B)a former volcanic island arc that migrated 10 000 km to its present location along the western margin of Europe.
C)a mountain range that became part of the Himalayas.
D)pieces of crust that moved with the Pacific plate to their present location near Japan.
E)crustal pieces that welded onto the western side of Australia.

Question 34

Which of the following is true of the magma formed from subducted ocean floor material that is eventually incorporated into continental crust?

A)the composition of the magma changes from a high silica content to a lower silica content by the incorporation of sediments and other materials when it melts.
B)the magma that forms in this way tends to produce more violent volcanic eruptions than magma derived directly from the aesthenosphere.
C)batholiths may create magma as they move downward into the subduction zone.
D)it has a low viscosity and rises easily to spread over the surface of the continental crust.
E)because this magma is exactly like the magma at sea-floor spreading centres,it creates new oceanic crust at the surface.

Question 35

When rock strata are strained beyond their ability to remain an intact unit,displacement occurs in a process known as

A)folding.
B)faulting.
C)broad warping.
D)stressing.
E)plastic flow.

Question 36

Which of the following is true of terranes?

A)they are larger-scale migrating crustal pieces i.e. ,microplates.
B)they may accrete onto continents and thereby increase the size of the continents.
C)they are destroyed by fracture zones.
D)they are very similar in composition to the continents to which they attach.
E)they can move tens of kilometres from their place of origin.

Question 37

Terranes refer to

A)the topography of a tract of land.
B)the "lay of the land."
C)displaced and migrating pieces of Earth's crust.
D)the continental shields within each continent.
E)layers of younger sedimentary rock that surround the craton.

Question 38

High mountains consisting of tightly folded and overthrust sedimentary rock layers,as well as metamorphic rocks,are formed

A)along midocean ridges during seafloor spreading activity and are subsequently uplifted above sea level in response to isostatic processes.
B)during plate collisions.
C)during volcanic eruptions.
D)in continental rift zones.
E)exclusively by magma intrusions.

Question 39

Warping produces bends in rocks that are ________ those produced by folding.

A)larger than
B)smaller than
C)the same size as

Question 40

Folded layers of rock can form a wavelike pattern of troughs and crests.The layers near the trough form

A)a syncline.
B)a tension zone.
C)an anticline.
D)a thrust fault.
E)a crustal intrusion.

Question 41

The San Andreas system in California is an example of a

A)an excarpment.
B)dome.
C)right-lateral motion in a stike-slip fault.
D)anticline.
E)thrusting in a normal fault.

Question 42

An area that is a seismic gap

A)is overdue for an earthquake,based on past earthquake frequency.
B)has significant surface fracturing due to fault movement.
C)has had tectonic plates separate,leaving large cracks in the surface.
D)is lacking seismometers or other measuring devices.
E)cannot have an earthquake because the rock cannot transmit energy.

Question 43

The area at the surface directly above the subsurface location where seismic waves are initiated is termed the

A)epicentre.
B)fault area.
C)Richter zone.
D)focus,or hypocentre.
E)mercalli centre

Question 44

The most active tectonic regions of North and South America are on the

A)western coasts.
B)eastern coasts.
C)southern coasts.
D)mid-continent.
E)at the highest latitudes.

Question 45

Orogenesis refers to

A)the beginning of extensive faulting.
B)a general term for a mountain-building episode that thickens continental crust.
C)a general thinning of the crust.
D)the formation of mountains without faulting,folding,or the capture of migrating terranes.
E)the deepening of the ocean through subduction in a trench.

Question 46

People often say that California is going to "fall into the ocean,".This idea is totally wrong because the San Andreas fault would have to be a ________ fault associated with ________ forces for this to happen.

A)normal tension
B)normal compression
C)reverse tension
D)reverse compression
E)strike-slip compression

Question 47

The Appalachians formed as a result of the

A)Laramide orogeny.
B)Alleghany orogeny.
C)Cordilleran orogeny.
D)Alpine orogeny.
E)Ellesmerian orogeny.

Question 48

Small areas of high strain along a fault are termed

A)asperities.
B)focal points.
C)elastic spots.
D)fore points.
E)seismic moments.

Question 49

The presence of grabens and horsts indicates the occurrence of

A)volcanic activity.
B)rift activity.
C)collision activity.
D)strike-slip activity.
E)transform faulting.

Question 50

The Innuitian Mountains formed as a result of the

A)Laramide orogeny
B)Alleghany orogeny
C)Cordilleran orogeny
D)Alpine orogeny
E)Ellesmerian orogeny.

Question 51

An instrument used to record vibrations in the crust is the

A)land barometer.
B)seismograph.
C)the Richter scale.
D)tiltmeter.
E)abney level.

Question 52

Which of the following regions is probably the most tectonically active at this time?

A)the Canadian shield
B)the Appalachian Mountains
C)the Himalayas
D)the Gulf Coast region of the United States
E)the prairies

Question 53

Seismic gap investigations involve

A)the study of surface cracks following an earthquake.
B)paleoseismology and the history of activity along specific plate boundaries.
C)perceptual studies by sociologists.
D)the study of places where volcanoes have occurred.
E)examining the record of magnetic reversal in the rock.

Question 54

Foreshocks may be caused by

A)frictional tension.
B)small movements that occur when some rocks break in limited areas of a fault plane prior to the main movement.
C)compressional tension increasing as energy is stored in the rock surfaces.
D)seismic moments.
E)isostasy.

Question 55

The motion of seismic waves is initiated in a subsurface area along the fault plane called the

A)epicentre.
B)fault area.
C)Richter zone.
D)focus,or hypocentre.
E)foreshock

Question 56

The relatively young mountains along the western margins of North and South American plates are referred to as the

A)Cordilleran system.
B)Eurasian-Himalayan system.
C)Alleghany orogeny.
D)Sierra Nevadan orogeny.
E)Sounoram orogeny.

Question 57

The presence of normal faulting and extensive basalt lava flows indicates

A)that compressional forces are affecting an area.
B)that magma is rising from a subducted ocean floor.
C)that strike-slip activity is occurring to a very large extent in an area.
D)that a rift zone is developing.
E)that subduction is occurring.

Question 58

Because of the processes responsible for the formation of the Himalayan Mountains,the crust in this region of the world has been

A)shortened.
B)extended.
C)thinned.
D)twisted.
E)stretched.

Question 59

Which of the following is produced by normal faulting?

A)the Himalayas
B)the Basin and Range
C)the San Andreas system
D)the Great Lakes lowlands
E)the Bay of Fundy

Question 60

The seven structural regions of the world

A)are grouped because of shared physical characteristics.
B)are defined based on latitude.
C)each correlate with a different continent.
D)are defined based on elevation.
E)have developed based upon the climate of the region in which they are located.

Question 61

A cinder cone is formed from relatively ________ viscosity magma with a ________ gas content.

A)high.high
B)high .low
C)low .high
D)low.low

Question 62

Which of the following is the result of intrusive volcanic activity?

A)batholith
B)lava flow
C)tephra
D)volcanic cone
E)pyroclasts.

Question 63

Molten rock that pours forth on Earth's surface is called

A)metamorphic.
B)magma.
C)intrusive.
D)lava.
E)ultramafic.

Question 64

Which of the following is true regarding the moment magnitude scale-a scale which quantifies the amount of energy released by an earthquake?

A)it is a scale of magnitude based on arithmetical progressions (1,2,3,4,etc. ).
B)it is a closed scale that begins at 0.0 and ends at 10.0.
C)an 8.0 on the scale is equal to 31.5 times more energy release than a 7.0.
D)it is the same as the Mercalli scale.
E)it is another name for the Richter scale.

Question 65

Lava plateaus,such as the Columbia River Plateau,are formed from ________ magma which has a ________ viscosity.

A)granitic .high
B)granitic .low
C)basaltic.high
D)basaltic.low

Question 66

Lava plateaus are formed from

A)felsic magma.
B)magma with a low silica content.
C)highly viscous magma.
D)a single vent.
E)episodic,explosive eruptions.

Question 67

Explosive eruptions tend to build up

A)shield-shaped volcanoes.
B)plateau basalts.
C)composite volcanoes.
D)many subsequent lava flows.
E)wide,flat platforms in the sea.

Question 68

Volcanic activity generally occurs

A)along the edges of shield terranes.
B)around the perimeter of the Atlantic Ocean basin.
C)in association with hot spots over plumes in the mantle and in the circum-Pacific belt.
D)in interior seas like the Carribean.
E)where continental plates collide.

Question 69

The wave amplitude associated with a magnitude 8 quake on the moment magnitude scale is how many times greater than that of a magnitude 6 quake?

A)3)15
B)31.5
C)63
D)992.25
E)31255

Question 70

Pulverized rock and clastic materials ejected violently during an eruption are called

A)cinders.
B)explosive debris.
C)tephra,or pyroclastics.
D)volcanic ash.
E)obsidian

Question 71

On average,how often would you expect an earthquake of between moment magnitude 5.0-5.9 and Mercalli V-VII to occur?

A)120 times a year
B)over a thousand times a year
C)only once every few years
D)once or twice a century
E)once a millenium

Question 72

Which of the following statements about shield volcanoes is true?

A)they occur in shield areas of Earth.
B)they are subject to violently explosive eruptions.
C)they form from mafic magma.
D)they consist of tremendous quantities of pyroclastics.
E)they develop when the lava is highly viscous.

Question 73

A scale used to classify and describe the effects of earthquakes on terrain,construction,and local damage conditions is the

A)Richter scale.
B)seismograph scale.
C)seismic assessment scale.
D)modified Mercalli scale.
E)moment magnitude scale.

Question 74

According to the text,a major impact of earthquake prediction on a region would be

A)a decline in business activity and damage to the local economy.
B)increased business activity.
C)an increase in property values.
D)upward changes in employment opportunities.
E)longterm economic devastation.

Question 75

Volcanic activity located away fromplate boundaries is associated with

A)subduction and melting of plates along collision zones.
B)hot spots.
C)rift zones.
D)crustal compression
E)tensional strain

Question 76

On average,how often would you expect an earthquake of greater than Richter 8.0 and Mercalli XII to occur?

A)120 times a year
B)800 times a year
C)only once every few years
D)once or twice a century
E)once in a millenium

Question 77

The phrase "considerable-to-serious damage to buildings" would be used in the ________ scale.

A)Richter
B)Mercalli
C)Beaufort
D)Moh's
E)moment magnitude

Question 78

Effusive eruptions are related to which of the following?

A)magma with a 50 percent or lower silica content,rich in iron and magnesium
B)high-viscosity magma
C)magma with a 50-75 percent silica content,high in aluminum
D)the volcanic activity near Mount St.Helens
E)on the Pacific coast of Canada.

Question 79

Volcanoes formed from silica-rich magma

A)have gently sloping surfaces that give them the appearance of a shield.
B)are highly explosive and dangerous.
C)are associated with midocean ridges.
D)are associated with rift zones.
E)have low viscosity lava.

Question 80

Many of the islands of Indonesia (Java,Sumatra,Borneo),which are located adjacent to a subduction zone next to the edge of the continental shelf of SE Asia,consist of felsic lava.This means that the lava which produces these islands is derived from

A)a midocean ridge.
B)a volcanic hot spot under the ocean floor.
C)the melting of continental shelf material along with ocean floor material.
D)the melting of subducted plate material and nothing else.
E)a rift zone.