Test 2: Volcanism Flashcards

1
Q

What are Pyroclastic Materials?

A

Magma fragments that are explosively ejected by volcanoes, most are solid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which Volcano?

Rhyolitic lava flows-most viscous
Very Explosive

A

Lava Domes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which Volcano?

Layers of lava flows and pyroclastic debris
Steep Cone Shaped
Intermediate compositions-andesite
Explosive
“Ring of Fire”`
A

Composite Volcanoes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which Volcano?

```
Gentle slopes and rounded shapes
Basaltic lava flows
Non-Explosive
Hawaiian Volcanoes
Komotilite
~~~

A

Shield Volcanoes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which Volcano?

Pyroclastic materials
Steep cones
Rarely exceed 400 m high

A

Cinder Cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

True or False?

The shape and eruptive style of volcanoes are related to the chemistry and viscosity of their magmas.

A

True

The shape and eruptive style of volcanoes are related to the chemistry and viscosity of their magmas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Rhyolitic lava flows:

A

Creates Lava Dome
Lava Dome holds in gases
Flows have broken and blocky surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Andesitic lava flows:

A

Flows slowly
Cone shape
Made up of Pyroclastic and lava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
Basaltic lava flows:
Flows fast (30-50km/hr)
A

Flows fast (30-50km/hr)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Komatiite lava flows:

A

Has not erupted in about 2.5 billion years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Silica Content

Rhyolite:

A

High silica content (70-75%)

High Viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Silica Content

Andesite:

A

Intermediate silica content (60-65%)

Intermediate Viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Silica Content

Basalt:

A

Low silica content (50-55%)

Low Viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Silica Content

Komatiite:

A
Limited Silica (Below 40%)
Very Low Viscosity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Fine: (No big crystals) (It’s lave) (Came to the surface) (Cooled first, causing crystals not being able to grow)

Extrusive Igneous Rock

A

Basalt, Andesite, Rhyolite, Komatiite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Course: (Big Crystals) (Didn’t come to the surface)

Intrusive Igneous Rock

A

Granite, Diorite, Gabbro, Peridotite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does Viscosity affect?

A

Viscosity affects the flow of lava and therefore the shape of the resulting volcano

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In explosive eruptions, _____is ejected

A

In explosive eruptions, tephra is ejected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an accumulation of tephra called?

A

An accumulation of tephra is a Pyroclastic deposit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the term for anything that explodes out of the volcano?

A

Pyroclastic is anything that explodes out of the volcano

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Molten rock material below the earth’s surface

A

Magma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Magma turns into a liquid when the surface is reached, creating lava

A

Lava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The viscosity of Magma is controlled by ______?

A

The viscosity of Magma is controlled by Silica Content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

More Silica causes a ______explosion

A

More Silica causes a bigger explosion (Builds up pressure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Less Silica makes for a ______explosion

A

Less Silica makes for a smaller explosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How do we have magma?

A

Decompression (Weight onto of it, prevents it from being liquid)

Addition of volatiles (Adding water breaks chemical bonds, creating fluid)

Addition of heat (When magma comes up it warms adjacent material, turning it into liquid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The tectonic setting determines the type of volcano
Mid-ocean ridges, subduction zones, hot spots

Mixing of Basalt and Granite create andesite which makes cone volcanoes

A

Subduction Zones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The tectonic setting determines the type of volcano
Mid-ocean ridges, subduction zones, hot spots

One section is moving one way and another section is moving a different way, the magma pushes through the weak spot creating lava.

A

Mid-Ocean Ridges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The tectonic setting determines the type of volcano
Mid-ocean ridges, subduction zones, hot spots

Magma is stationary, but the plates are moving so there is a build-up of magma pressure which creates small islands.

A

Hot Spots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Where does the Ring of Fire surround?

A

The Ring of Fire surrounds the Pacific Ocean. (Surrounds Pacific Ocean) (Subduction zones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How many of all active volcanoes on land are located along the Ring of Fire which surrounds the Pacific Ocean?

A

2/3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Popular Volcanoes

Still active (Pompeii)

A

Mount Vesuvius, Italy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Popular Volcanoes

“Year without summer” (Ash shot in the air everywhere)

A

Tambora, Indonesia

34
Q

Popular Volcanoes

57 people died) (Internal Explosion

A

Mount St Helens, United States

35
Q

Popular Volcanoes

Airline disaster, ash coverings in sky

A

Mt. Eyjafjallajökull, Iceland

36
Q

What are the volcanoes in Japan, Mexico, the Philippines, and Indonesia known as?

A

(Killer Volcanoes)

37
Q

How many volcanoes erupt each year on Earth?

A

50-60 volcanoes erupt each year

38
Q

Where are the most active volcanoes located in our solar system?

A

Jupiter’s moon - IO has the most active volcanoes

39
Q

Tidal Forcing:

A

Moon’s gravitational pull on a planet

Jupiter’s mass is so massive that it squeezes the moon (IO), it heats up the moon causing lava flows.

40
Q

Where is the largest volcanic mountain?

A

Olympus Mons has the largest volcanic mountain (Mars)

While Earth has more volcanic features, Mars has the largest
Magma pushes and silicifies, this creates a large pile up creating big volcanic features.
Volcanoes - Dormant

41
Q

True or False:

All volcanoes are destructive

A

False:

Not all volcanoes are destructive

42
Q

True or False:

Pyroclastic material is the most dangerous

A

True

Pyroclastic material is the most dangerous

43
Q

How to get an accurate representation of the surface on Venus?

A

Radar can go through cloud cover (Gives an accurate representation of the surface)

44
Q

How many major volcanoes or volcanic features are there on Venus?

A

1,600 major volcanoes or volcanic features

45
Q

Is volcanism still on Venus?

A

Evidence shows that in the volcanic mountains there is still heat, meaning volcanism might still be on Venus.

46
Q

What are volcanic gases primarily made up of?

A

Water Vapor (lesser amounts of carbon dioxide)

47
Q

Craters:

A

Depressions formed by explosions or collapse of volcano top. (1km wide)

48
Q

Calderas:

A

Volcano colossus into magma chamber following violent eruptions (thousands of metres across, hundreds of metres deep).

49
Q

Lava Tubes:

A

Forms a crust which silicifies, causing the creation of a tunnel (50 km/hr)

50
Q

Vents:

A

Any opening for lava and debris
Can produce flood basalts
Both on water and on land (Along mid-ocean ridge)

51
Q

Hot Springs:

A

Hot rocks heat groundwater; discharge at the surface

Blue Lagoon

52
Q

Geysers:

A

Groundwater boils, erupting at the surface. Water turns into steam and erupts
Yellowstone national park

53
Q

Pyroclastic Sheet Deposits:

A

Huge sheet-like eruptions of pyroclastic materials

54
Q

Where would you find Lava Lakes?

A

In Africa

55
Q

Erupt beneath or against glaciers
Subglacial volcanoes erupt, rapidly melting ice and produce huge floods known as Jokulhlaups
Huge flood from glacier volcanoes (Iceland, Mt. Garibaldi)

A

Ice Contact Volcanoes:

56
Q

Volcanic Hazards

Primary Effects:

A

Lava flows, ashfall, volcanic bombs, pyroclastic flows, pyroclastic surges, lateral blast (Mt.St.Helens), and poisonous gases.

57
Q

Volcanic Hazards

Secondary Effects:

A

Lahars, debris avalanches, landslides, groundwater and surface contamination, floods, fires, and tsunamis.

58
Q

The size of an eruption can be quantified using a scale called the ______?

A

Volcanic Explosivity Index (VEI)

59
Q

Volcanic Hazards: Ash

A

Ash is blown high into the air and falls onto areas.
Ash can cause its own lightning from rubbing against each other.
Causes health hazards (It can burn you)
(Mt. Eyjafjallajokull)

60
Q

Causes of volcanic ash

A

Vegetation Destroyed
Contaminates Surface Water
Damage to buildings
Aircraft Engine Failure

61
Q

British Airways Flight 009:

A

Flew into a cloud of volcanic ash (Mt. Galunggung near Jakarta, Indonesia)
All 4 Engines went out

62
Q

Biggest flight distribution since 9/11

The ash plume drifted between 6,700 m and 11000m (2000 km away)

A

Mt. Eyjafjallajokull:

63
Q

Occurs when magma reaches the surface

Can move slowly or rapidly depending on viscosity and temperature

A

Lava Flows:

64
Q

What is the most common lava flow?

A

Basaltic lava flows are the most common

65
Q

Types of Lava Flows

Pahoehoe:

A

Hardens with a smooth ropy texture

Travels at speeds up to a few kilometres per hour

66
Q

Types of Lava Flows

Aa:

A

Harden’s with a rough, blocky texture

More vicious travels at rates of a few metres per day

67
Q

3 ways to Divert Lava Flows:

A

Bombing:

Hydraulic Chilling:

Wall Construction:

68
Q

Diverting Lava Flow:

Bombing:

A

Block channels to cause low flows to take a less damaging route

69
Q

Diverting Lava Flow:

Hydraulic Chilling:

A

Water used to chill and control lava flows (Iceland)

70
Q

Diverting Lava Flow:

Wall Construction:

A

Walls are used to redirect lava flows

71
Q

What is the most dangerous lava flow?

A

Pyroclastic flows are most dangerous (400 km per hour) Pompeii

72
Q

Avalanches of hot rock, Ash, volcanic rock fragments

A

Flows

73
Q

Dense clouds of hot gas and rock debris produced by explosive interaction of water and magma

A

Surges

74
Q

Nuée Ardente:

A

A turbulent, fast-moving cloud of hot gas and ash erupted from a volcano

75
Q

Lateral Blasts:

A

Rock fragments, gas, and ash that are blown horizontal from the side of the volcano
For example: Mount St. Helens
Lahars: Aftermath of Mt. St. Helens
Forecast eruptions but can’t predict them

76
Q

Who believed the situation was over-exaggerated and ended up dying from not evacuating?

A

Harry Truman (Spirit Lake Lodge)

77
Q

Poisonous Gas

Odourless, heavy gas that can displace breathable air.

A

Carbon dioxide (CO2):

78
Q

Poisonous Gas

Odorous gas that causes acid rain and can contaminate rock and soil.

A

Sulphur Dioxide:

79
Q

Lahars?

A

Large amounts of loose volcanic ash and other pyroclastic material become saturated with water and rapidly move downslope

80
Q

Why Do People Live Near Volcanoes?

A
Place of birth
On some islands, all land is volcanic
Fertile land for farming
Believe Interruption is unlikely
Unaware of risk
Economic limitations
81
Q

Natural Service Functions:

A

Volcanic Soils:
Good for coffee, maize, pineapples, sugar cane, and grapes

Geothermal Power:
Can create energy for nearby urban areas

Mineral Resources:
Gold, silver, etc. And non-metallic rocks
Used for soap, building stone, aggregate for roads, railroads, etc

Recreation:
Health Spas in Hot Springs
Hygiene, snow sports, and education
Kilauea National Park

Creation of New Land:
Hawaiian Islands

82
Q

Is it possible to Forecast Eruptions?

A

YES!

Monitoring involves recording and analyzing both physical and chemical changes at volcanoes.

Tiltmeters and geodimeters to detect changes in slope, elevation, and shape.
Seismometers to detect harmonic tremors
Gas emissions, thermal, magnetic and hydrologic monitoring are also measured