02 Geomorphology

GEOMORPHOLOGY

Complete the following questions by selecting the corresponding letter which matches the correct answer. 1.

The process whereby lithospheric plates come together is called:

a) b) c) d)

divergence convergence sea floor spreading translation

2.

Molten rock that comprises the upper part of the mantle is referred to as:

a) b) c) d)

lithosphere asthenosphere mesosphere biosphere

3.

A large, irregularly shaped section of the earth that floats on the molten centre is called a:

a) b) c) d)

continent ridge plate trench

4.

The earth’s crust is comprised of a series of large plates that carry both oceanic and continental crust on their back. These plates “float” on the mantle as the plates are:

a) b) c) d)

less dense than the mantle beneath them more dense than the mantle beneath them of similar density to the mantle beneath them exact density to the mantle beneath them

5.

Convergent plate margins occur when:

a) b) c) d)

any two plates collide any two plates diverge sea floor spreading occurs translation occurs

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6.

If two plates were to collide, what possibilities may result?

a) b) c) d)

mountainous regions earthquake activities volcanic activity all of the above

Questions 7–9 refer to the plate tectonics map below:

7.

The names given to the plate number 8 and 4 respectively are:

a) b) c) d)

Nazca and Indo-Australian African and Asian Pacific and Indonesian South American and Indo-Australian

8.

The dotted lines represent:

a) b) c) d)

subduction zones major earthquake activity plates moving apart plates coming together

9.

The feature labelled as A is: Page 17

a) b) c) d)

the Mid-Atlantic Ridge South East Indian Rise San Andreas fault line a rift valley

10. a) b) c) d)

External forces that bear down and wear away the earth’s surface are known as: vulcanism diastrophism gradation tectonics

11.

The black dots on the world map below are representative of only:

a) b) c) d)

collision zones active volcanoes subduction zones spreading ridges

12.

The process where plate margins are drawn into the mantle is:

a) b) c) d)

divergence translation subduction vulcanism

Questions 13-16 refer to the diagram below: Page 18

B

A

13.

The resultant feature formed at location A is a:

a) b) c) d)

volcanic mountain chain fold mountain range mid ocean ridge volcano

14.

This feature formed at A has resulted from:

a) b) c) d)

the melting of the subducting oceanic plate the melting of the subducting continental plate the scraping of sediment along the continental plate an increase in pressure within the lithosphere

15.

This destructive process involves which two plates?

a) b) c) d)

oceanic & oceanic continental & continental continental & oceanic all of the above

16.

The movement of these two plates and the resulting features produced illustrate the destructive process of:

a) b) c) d)

translation divergence:subduction convergence:collision convergence:subduction

17.

Which of the following lists describes in the correct order the earth’s crosssection from the innermost to outermost layer: Page 19

a) b) c) d)

core / mesosphere / asthenosphere / lithosphere core / asthenosphere / mesosphere / lithosphere lithosphere / core / mesosphere / asthenosphere core / lithosphere / mesosphere / lithosphere

18.

Convection currents are believed to be responsible for initiating movement of the lithospheric plates. These currents are thought to originate from the:

a) b) c) d)

mesosphere core asthenosphere mantle

19.

The diagram below illustrates a particular current type, where warm air rises and sinks downwards as it eventually cools:

a) b) c) d)

convection thermal conduction rising

20.

The earth’s landforms have been shaped through internal forces. These forces which originate from below and build up the earth’s surface is referred to as:

a) b) c) d)

diastrophism vulcanism tectonics gradation

21.

The gap that results from the divergence of two oceanic plates is a:

a) b) c) d) 22.

trench fault central valley ridge A “v” shaped depression that results from subduction is: Page 20

a) b) c) d)

a ridge an ocean deep a central valley an island arc

23.

The sideways movement of two lithospheric plates is classified as:

a) b) c) d)

divergence translation laterisation convergence

24.

Divergence is illustrated by number:

Plate 1

Plate 2 continent

A

Plate 3

B

D

C

continental crust

oceanic crust E convection currents

mantle

a) b) c) d) e)

C A B D E

25.

The Ring of Fire refers to the arc of:

a) b) c) d)

seismic activity along the rim of Pacific ocean volcanic activity along the rim of the Atlantic ocean seismic and volcanic activity along the rim of the Atlantic ocean volcanic and seismic activity along the rim of the Pacific ocean

26.

Which of the following statements is correct?

a)

secondary earthquakes occur only during the collision of plates Page 21

b) c) d)

island arcs occur from the convergence of oceanic plates subduction results in new ocean floor being created island arcs occur from the divergence of oceanic plates

27.

The Mid Atlantic Ridge and South East Indian Rise result from:

a) b) c) d)

subduction convergence translation divergence

28.

Which of the following statements is correct?

a)

converging boundaries or constructive boundaries occur at trenches where two plates come together diverging boundaries or destructive boundaries occur at mid ocean ridges where two plates move apart diverging boundaries or constructive boundaries occur at mid ocean ridges when two plates come together converging boundaries or destructive boundaries occur at trenches where two plates come together

b) c) d)

29.

Geomorphology:

a)

refers to the processes which build up the earth’surface through buckling and folding studies the arrangements of patterns of landforms on the earth’s crust studies the breaking up of the continents into their present day configuration studies forces that occur within the earth’s mantle

b) c) d) 30.

The Mid Atlantic Ridge is formed through the spreading of which sets of plates?

a) b) c) d)

Nazca and South American Antarctic and Australian African and Eurasian South American and African

31.

Through which tectonic movement are the Alps created?

a) b) c) d)

convergence: oceanic plate & continental plate convergence: continental plate & continental plate convergence: oceanic plate & oceanic plate divergence: continental plate & continental plate

32.

The world’s most famous fault line is the:

a)

San Andreas Page 22

b) c) d)

African Rift Mid Atlantic South East Indian

33.

A normal fault is best depicted by which diagram below?

a)

b)

c)

d)

34.

The supercontinent thought to have existed over 200 million years ago is named:

a) b) c) d)

Gondwana Laurasia Pangea Gwondana

35.

It is believed that through the process of continental drift, the continents have slowly moved to their present day configuration across a period of millions of years. Through this drift process, it is theorised that Page 23

Australia, Antarctica and Africa were once joined together to form a great southern section of land known as: a) b) c) d)

Laurasia Gondwana land Pangea Southern Land Question 36 refers to the Continental Drift diagram below:

splits

135 million years ago

36.

This stage of Continental Drift a proposed 135 million years ago, illustrates Laurasia comprised the continents of:

a) b) c) d)

Asia and Europe North America and Europe North America, Asia and Africa Asia, Europe and North America

*37.

A laccolith is:

a) b) c) d)

horizontal solidified magma between rock layers a vertical pipe of solidified magma a solidified magma reservoir an igneous intrusion of magma forming a dome like structure

38.

A horizontal sheet like mass of volcanic rock that intrudes between layers of sedimentary rock: Page 24

a) b) c) d)

sill batholith dyke laccolith

39.

Metamorphic rocks are:

a) b) c) d)

fire formed secondary rocks tertiary rocks primary rocks

*40.

Pluton plugs are a result of weathered:

a) b) c) d)

solidified dykes sills laccoliths solidified cores

41.

Limestone, shale and sandstone are examples of which rock type:

a) b) c) d)

sedimentary igneous metamorphic intrusive

42.

Rocks which undergo a change in rock texture, structure or colour are referred to as:

a) b) c) d)

sedimentary metamorphic granitic igneous

43.

Basalt is an example of which rock type?

a) b) c) d)

igneous sedimentary metamorphic secondary

*44.

The Benioff zone refers to:

a)

the zone of grinding during subduction Page 25

b) c) d)

the resulting “v” shaped depression the crumple zone of fold mountains the edge of the subducting plate

*45.

Mohorovicic Discontinuity is the boundary between the:

a) b) c) d)

mesosphere and asthenosphere core and asthenosphere crust and mantle core and mantle

46.

The Japanese Archipelago is created through the process of which two plates converging?

a) b) c) d)

Eurasian and Pacific Eurasian and African Pacific and Indo-Australian Juan de Fuca and Eurasian

47.

Molten rock that is able to find a weakness in the earth’s crust to reach the earth’s surface is called:

a) b) c) d)

asthenosphere lava magma crust

48.

Anticline refers to:

a) b) c) d)

the upfolds of folding crust the valleys or downfolds of folding crust the valleys or upfolds of diverging crust the upfolds of diverging crust

49.

This complex fold is identified as a:

a) b) c)

nappe monocline cross-over fold Page 26

d)

bend

50.

The major opening around which a volcano occurs:

a) b) c) d)

pipe caldera crater vent

51.

Which of the following statements regarding a caldera are false? A caldera:

1. 2. 3. 4. 5. 6.

is a large crater is the central channel of a volcano is formed through the collapse of the summit cone may have secondary cones develop through subsequent eruptions may become filled with water to form a lake is a dome like peak that may be removed from an eruption

a) b) c) d)

1,2 & 6 1,3,4 & 5 2&6 4&6

52.

Which of the following statements regarding subduction is true?

1. 2. 3. 4. 5. 6.

It results in ejected magma solidifying to produce new sea floor Involves the collision of two oceanic plates Results in the formation of volcanic mountain ranges May involve the convergence of an oceanic and continental plate Produces a series of fold mountains The less dense plate will always subduct

a) b) c) d)

3,4,5 2,3,4 1,2,3 & 6 2,3,4 & 5

53.

Volcanoes that no longer erupt and are classified as in a state of permanent inactivity are:

a) b) c) d)

dormant active extinct eruptive

54.

A dormant volcano is one that has:

a)

eroded down to a volcanic plug Page 27

b) c) d)

no record of eruption erupted and is likely to continue to erupt erupted within historic times but not recently

*55.

Which of the following statements regarding acid lava is correct? Acid lava is:

a) b)

is thick and viscous and does not flow easily, forming a steep cone. flows more easily and spreads over a large area, forming a gently sloping volcano forms a gently sloping strata volcano of ash and lava flows easily forming a steep cone near vent Which order classifies pyroclastic materials in size order, from the smallest to largest ejections?

c) d) *56. a) b) c) d)

bombs, cones, pumice, ash, dust dust, ash, cones, pumice, bombs ash, dust, pumice, cones, bombs dust, ash, pumice, cones, bombs

57.

The Hawaiian Island chain is formed through which tectonic process?

a) b) c) d)

hot spot activity subduction divergence island arcs

*58.

Steam ejections from super heated water are most commonly found in:

a) b) c) d)

fumeroles geysers mud holes nuées ardentes

*59.

Which one of the following features in list 1 correctly matches its description in list 2? LIST 1

a) b) c) d) 60.

LIST 2

geyser

eruptions of hot water and steam through a pipe hot spring steam mixed with volcanic dust to produce bubbling mud fumerole super heated water mixed with cool groundwater mud pot water turned to steam that is released from the ground What feature is represented by the letter A?

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A

a) b) c) d) e)

cone volcanic plug caldera crater vent

61.

A composite volcano is so named due to the:

a) b) c) d)

acidic composition of the ejected ash alternate layers of lava and ash volcano consisting of many layers steepness of the volcanic sides produced through eruptions Questions 62-63 refer to the plutonic cross section below:

E A B

C

D

62.

What intrusive volcanic feature is illustrated by point A?

a)

dyke Page 29

b) c) d)

batholith sill laccolith

63.

A batholith is represented by which letter?

a) b) c) d)

C D B E Questions 64–67 refer to the volcanic cross section diagram below:

4

1

6

2

7

3

5

64.

The volcanic feature numbered 2 is a:

a) b) c) d)

fumerole secondary pipe crustal weakness vent

65.

A plug is represented by number:

a) b) c) d) e)

7 6 1 4 5

66.

Number 3 would best match which description?

a)

solidified lava in the pipe of a volcano Page 30

b) c) d)

the bowl shaped mouth of a volcano weakness in the crust through which magma can escape molten liquid rock held under pressure beneath the earth’s crust

67.

Mt Pinatubo is an active volcano located in:

a) b) c) d) e)

the Philippines Italy Hawaii Columbia Indonesia

68.

The volcanic diagram below is an example of which volcano type? explosive eruption

ash pellets

a) b) c) d) e)

composite shield cinder gaseous mixed

69.

The point of origin of an earthquake is the:

a) b) c) e)

centre focus point epicentre

70.

The place on the earth’s surface above the point of origin of an earthquake is called:

a) b) c) e) 71. a) b)

focus centre epicentre origin The strength of earthquake vibrations are measured through which instrument? seismograph richtergraph Page 31

c) d)

wave recorder tremomometer

72.

Which of the following statements is false concerning the richter scale?

a) b) c) d)

it is a logarithmic scale it is an open ended scale it is a closed scale, ten being the largest quake to be measured an earthquake registering 6 produces 10 times as much energy as an earthquake registering 5

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