Deck 6: Volcanoes and Igneous Rocks

Question 1

Molten rock that reaches Earth's surface is known as _______.

A)magma
B)tephra
C)lava
D)pyroclasts
E)fumaroles

Answer 1

C

Question 2

The igneous rock in the figure below has what type of texture?

A)glassy
B)aphanitic
C)phaneritic
D)porphyritic
E)none of the above

Answer 2

A

Question 3

Fine grained igneous rocks have a(n)_______ texture.

A)aphanitic
B)phaneritic
C)porpyritic
D)glassy
E)vesicular

Answer 3

A

Question 4

Which of the following terms best describes the lava in the figure below?

A)low viscosity
B)high viscosity
C)crystallized
D)fractionated
E)none of the above

Question 5

Which of the following is the name for a fine-grained,felsic igneous rock?

A)granite
B)basalt
C)andesite
D)pumice
E)rhyolite

Question 6

What is the difference between magma and lava?

A)the chemical composition
B)the amount of water that each holds
C)lava reaches the surface and magma does not
D)the amount of molten rock with or without pyroclasts
E)the amount of dissolved gases and suspended crystals

Question 7

The degree to which a substance resists flow is known as _______.

A)magma
B)composition
C)tephra
D)fumaroles
E)viscosity

Question 8

_______ igneous rocks are composed of dark-colored minerals rich in magnesium and iron.

A)felsic
B)mafic
C)intrusive
D)vesicular
E)extrusive

Question 9

A _______ is a mixture of molten and solid rock.

A)tephra
B)pyroclastic flow
C)fractional melt
D)debris flow
E)complete melt

Question 10

The figure below has what type of texture?

A)glassy
B)aphanitic
C)phaneritic
D)porphyritic
E)none of the above

Question 11

In the figure below,rocks at a depth of 300km will have associated pressures of about _______.

A)1,000mpa
B)2,000mpa
C)5,000mpa
D)10,000mpa
E)15,000mpa

Question 12

The smallest type of tephra is known as _______.

A)lapili
B)volcanic ash
C)agglomerates
D)pyroclasts
E)calderas

Question 13

Igneous rocks that cool underground from a magma are known as _______.

A)volcanic rocks
B)extrusive rocks
C)plutonic rocks
D)neptunic rocks
E)none of the above

Question 14

The composition of most magma is 40%-75% ________ by weight.

A)silicates
B)oxides
C)aluminums
D)magnesian minerals
E)none of the above

Question 15

The Hawaiian Islands are composed of what type of volcanoes?

A)shield
B)stratovolcanoes
C)cinder cones
D)flood basalts
E)none of the above

Question 16

In the figure below,which of the igneous intrusive bodies is parallel to pre-existing bedding?

A)xenolith
B)batholith
C)pluton
D)sill
E)dike

Question 17

In the figure below,rocks at a temperature of _______ have pressures of approximately 5000mpa.

A)200ºC
B)500ºC
C)2000ºC
D)1000ºC
E)1400ºC

Question 18

Large,loose pyroclasts welded together during an eruption are known as _______.

A)tuff
B)agglomerates
C)tephra
D)resurgent domes
E)fumaroles

Question 19

According to the figure below,the temperature of oceanic crust does not exceed _______?

A)200ºC
B)500ºC
C)1400ºC
D)1000ºC
E)1500ºC

Question 20

The figure below is an igneous rock with what kind of texture? Hint: Do not be confused by the holes.

A)glassy
B)aphanitic
C)phaneritic
D)porphyritic
E)groundmass

Question 21

A volcanic pipe is a remnant of a channel that once fed magma to the vent.

Question 22

Igneous rocks high in feldspars and silicates are known as felsic rocks.

Question 23

Volcanologists can often tell an eruption is eminent because of changes in .

A)seismic activity
B)gas emissions
C)ground and water temperatures
D)the slope of a volcano's flanks
E)All of the previous

Question 24

The presence of higher amounts of water usually results in the lowering of the melting temperature.

Question 25

Mt.St.Helen's erupted on May 18,1980 and blanketed most of the northwestern United States with ash.

Question 26

When magma re-enters a magma chamber causing the floor of the caldera or crater to lift,the resulting structure is called a _______.

A)fissure
B)geyser
C)fumarole
D)resurgent dome
E)thermal spring

Question 27

According to the figure below,an increase in depth results in an increase in melting temperature.

Question 28

In the figure below,albite crystals will melt slower as a result of an increase in temperature rather than an increase in pressure.

Question 29

The ejecta from a volcano are collectively known as tephra.

Question 30

When groundwater comes in contact with hot rock,it heats up and creates a resurgent dome.

Question 31

In the figure below,beaker #2 is the closest to having a 25% melt.

Question 32

Pumice forms from the slow cooling of lava that froths and bubbles.

Question 33

Hawaiian eruptions are extremely violent and produce large pyroclastic flows.

Question 34

Crater Lake in Oregon is the remnants of a stratovolcano named Mount Mazama.

Question 35

Small pyroclasts welded together during an eruption results in the formation of a tuff.

Question 36

Normally,Earth's geothermal gradient increases approximately 10.2ºC per kilometer of depth.

Question 37

Beneath the surface,rocks completely melt at about 1000ºC.

Question 38

A separation of melted materials from remaining solid materials during the course of melting is known as crystallization.

Question 39

The person in the figure below was encased by a pyroclastic flow.

Question 40

Pyroclastic flows are composed of hot volcanic fragments (tephra)that flow very rapidly,due to the presence of heat and volcanic gases.

Question 41

Shield volcanoes can commonly extend more than 10 km in height from their bases.

Question 42

The most violent volcanic eruptions in history are classified as _______ eruptions.

Question 43

An extinct volcano shows no signs of activity.

Question 44

When lava rises to the surface through long fissures rather than a crater,the resulting formation is a broad,flat lava plain called a(n)_______.

Question 45

Devil's Tower in Wyoming is a good example of a volcanic neck.

Question 46

Rocks usually melt _______as fast under the seafloor as under the continents.

Question 47

Sulfur dioxide,which is released during volcanic eruptions,forms small droplets in the atmosphere called _______.

Question 48

When magma is injected horizontally between layers and solidifies,a(n)_______ forms.

Question 49

According to the table below,darker colored igneous rocks result from a(n)_______ in silica.

Question 50

Basaltic magma has a high amount of dissolved gases and is very explosive.

Question 51

The volcanic lake in Cameroon that released carbon dioxide and killed 1700 people in 1986 is called _______.

Question 52

Satellite images can be used to detect changes in a volcano's surface temperature.

Question 53

_______ are volcanic vents that emit only gas.

Question 54

In the figure below,_______ is the process that occurs when newly formed crystals are lighter than magma and float to the top of the magma chamber

Question 55

A Strombolian eruption produces cones of loose volcanic rocks known as _______.

Question 56

The deaths of the residents of Pompeii and Herculaneum in 79 A.D.is the result of a _______ effect of the volcanic eruption of Mount Vesuvius.

Question 57

Vulcanian eruptions are not very explosive and only release ash 5km into the air.

Question 58

is an example of a mafic,plutonic igneous rock.

Question 59

Scientists can never predict when a volcano will erupt.

Question 60

Intermediate sized tephra is called _______.

Question 61

The magma from erupting volcanoes has a temperature ranging between ________.

Question 62

Describe why stratovolcanoes are found in the "Ring of Fire."

Question 63

The mass of bubbles found in pumice are more commonly known as _______.

Question 64

Contrast igneous rock textures between those formed internally (intrusively)and those formed externally (extrusively).

Question 65

What is the correlation between volcanoes and plate boundaries?

Question 66

What are flood basalts?

Question 67

The eruption of _______ in 1815 resulted in the "year without a summer".

Question 68

In the figure below,please discuss the correlation between atmospheric temperature and acidity of the volcanic eruption.

Question 69

Discuss how large eruptions like Mt.Pinatubo in 1991 and Tambora in 1815 affected Earth's climate.

Question 70

Igneous rocks with about 60% silica by weight have a(n)_______ composition.

Question 71

_______ is the separation of melted materials from the remaining solid material during the course of melting.

Question 72

How does the presence of water affect the melting temperature of a rock?

Question 73

Discuss the relationships between gabbro and basalt and granite and rhyolite.

Question 74

In the figure below,what is the correlation between temperature and pressure?

Question 75

_______ magma contains more dissolved gases and tends to be more explosive.

Question 76

Igneous rocks with small crystals undergo _______ cooling.

Question 77

The texture of igneous rocks that contain large crystals set in a finer matrix is known as _______.

Question 78

The separation of liquids from crystals during crystallization is known as _______.

Question 79

What is the difference between a sill and a dike?

Question 80

Aside from lava flows,what are some additional hazards associated with volcanoes.