Mountains and Volcanoes – Questions ANSWERS
1. A mountain can be defined as:
A natural elevation of the earth’s surface, rising abruptly from the
surrounding level. – steep hill.
2. Orogeny means:
The name given for the processes of mountain forming
3. An orogenic belt is:
Long tracks of highly deformed rock that run in parallel strips
exhibiting similar characteristics along the entire length of the
belt.
4. How long does it take for a orogenic belt to typically form?
It can take tens of millions of years.
5. Identify and describe the two main ways/processes a mountain can
form.
Deformation – continental collisions resulting in folding and faulting
Volcanic Activity – opening in crust which allows magma to escape and
form a volcanic mountain.
6. Complete the graphic organizer attached identifying the main type of
mountains.
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7. What are the differences between a shield volcano, a stratovolcano
and a cindercone volcano? Fill in chart below.
Overall shape:
Cindercone
Volcano
Wide base,
gradual slope,
small crater
Characteristics Lava fragments
Magma and
are called
Lava:
cinders
Shield Volcano
Strato Volcano
Wide base, low
Wide base, low
grade slope, large grade slope, wide
crater
crater
Lava is runny and
flows like a river
Magma is thick
and sticky and
easily clogs
crater.
Type or
Lava is ejected
Does not explode. Most violent
Eruption
from one vent
Just heads and
eruption –
and deposits
melts the above
explodes and
around that vent. rock.
blows rock and
ash everywhere.
Typically found Found near
Can be found
Found near
(i.e. on plate
subduction zones anywhere on a
subduction zones
boundaries)
(where oceanic
plate – does not
(where oceanic
and continental
have to be along
and continental
plates collide)
a boundary
plates collide)
8. Where is Mount St. Helens found? What type of volcano is it? How
can you tell this?
It is found in Washington on the west coast of USA. It is a
stratovolcano because when it erupts – it spews rock and ash.
9. How do the formations of mountains and volcanoes relate to the
theory of plate tectonics?
Both mountains and volcanoes result from tectonic activity. Mountains
from collision of continental plates; volcanoes from hot spots or
collision of oceanic and continental plates.
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10. Research the Iceland volcanic eruption that began April 10. 2010 at
the Eyjafjallajökull Volcano. Based on your research: identify the
type of volcano (be sure to include how you know this (ie. Nature of
eruption, etc.) the nature of the eruption, how long the eruption
lasted, the impact on humans.
Type of Volcano – Stratovolcano
Evidence – created a rock and ash cloud that extended over much of
Europe for days.
Nature of Eruption – violent, and lasted months until the eruption finally
stopped in October of that year.
Human Impact – loss of homes, airways were blocked: planes could not fly
to/from Iceland and many European countries nearby. Farmland and
livestock were also greatly impacted.
11. Research how a volcanic eruptions can affect the environment and
climate and list below affects below.
Volcanoes that release large amounts of ash into the atmosphere can
cause sun rays to be reflected away from the earth’s surface causing air
temperatures to decrease. Increased amounts of rain are also common in
areas with this type of eruption occurs as water likes to attach to these
ash particles causing a lot of rain and thunderstorms.
12.
Is Halifax located on a foreland or a craton? Explain.
Is is located on a craton. Why? Because we are located in the middle
of the North America plate. A foreland is the area of land right
beside a mountain range and Halifax is not right beside a mountain
range.
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13. Why are there no active volcanoes in the eastern parts of North
America?
Because there are no: hot spots in the area or subduction zones
(collision of oceanic and continental plates) to create volcanoes.
14.
What are some benefits to volcanic activity?
They produce fertile soil for growing many crops, they can create
new land (volcanic islands such as Iceland and Hawaiian Islands),
Gems and minerals are found here too.
15. What are the differences between active, dormant, and extinct
volcanoes?
Active: volcanoes that have at least one eruption during the last 10,000
years.
Dormant: volcanoes are active but no eruptions but are expected to.
Extinct: volcanoes that have not erupted for over 10,000 years.
16. What are the similarities and differences between mountains and
volcanoes?
Similarities: both can result from the collision of plates.
Volcano – through collision of oceani/continental at a subduction zone.
Mountains – though collision of two continental plates
Similarities: mouth are sloped, elevated land masses
Differences: Mountains wont release magma
Differences: Mountains are due to uprising of crust, Volcanoes build due to
the release of lava.
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