HAZARDS 20 MARKERS
VOLCANOES
Analyse the role of plate margins in influencing the risk posed to people by volcanic hazards
[9 marks]
Plate margins play a significant role in influencing the risk posed to people by volcanic
hazards. Destructive and constructive margins can cause a change in the severity of
volcanic hazards. However, there are arguably other factors involved in creating a greater
level of risk to the population, such as the location of the volcano.
The nature of plate boundaries is significant in relation to the severity of hazards, and the
risks they pose to people. Volcanoes can form on both constructive and destructive plate
margins. At a destructive margin, the dense oceanic plate descends below the continental
plate. Heat from friction and the core melt the plate into magma which rises as plutons.
These reach the surface to form composite, explosive volcanoes. These volcanoes can have
severe impacts on the place they affect, as andesitic lava is associated with ash, tephra, and
pyroclastic flows, which can cause devastation to human life as well as the built environment
and the economy. These hazards can impact the area surrounding the volcano which can
have global affects as the large ash clouds can block out sunlight and contribute to climate
change. The Ring of Fire provides an example of these volcanoes, as it co sits of 755 of the
worlds volcanos, located around the Pacific Ocean. At constructive margins, the brittle crust
breaks as the plates diverge, dropping between parallel faults to form rift valleys. This crust
is thinner, so basaltic magma forces its way upwards to form volcanoes such as shield
volcanoes, which are less explosive. This demonstrates the influence of plate margins on the
risk posed to populations.
On the other hand, it could be argued that the location of a volcano plays a larger role in
influence in the risk posed to people by volcanic hazards. Eyjafjallajökull is situated on a
constructive plate margin, therefore should have less of an impact on the population, yet
other physical factors meant that there was an extremely powerful eruption in April 2010.
The volcano is situated on ice caps, therefore when the volcano erupted, the ice melted
which caused severe flooding and ash clouds. The ash was particularly damaging for the
local area, as when the magma hit the ice, it called, forming glass like material. Explosions of
gas in the main vent caused these abrasive shards to become tiny particles, which were
dispersed by the cloud and endangered engines of aircraft, costing airlines £130 million a
day each day of the eruption. This meant that the locals were unable to leave the area and
people became stranded. This shows that, although plate boundaries are important, other
physical factors like the location of the volcano are important in determining the levels of
impact.
In conclusion, although plate margins can influence volcanic hazards, location can be
argued to be a more important factor determining the risk posed to people. Eyjafjallajökull is
a clear example of this.
How far do you agree that secondary impacts of volcanic eruptions present a greater long-
term threat to people than primary impacts? [9 marks]
I agree to some extent. Primary volcanic impacts, such as pyroclastic flows an ash clouds,
have the ability to present significant long term threat to populations. However, secondary
impacts, including tsunami’s and climate change, have the ability to cause more long term
disruption, as well as wider spread effects.
Pyroclastic flows are hot, gas charged flows of gas and tephra that can travel up to 700
kilometres per hour. These flows have the power to cause mass destruction of an area, and
little can be done to intervene, for example, Pompeii was destroyed by these flows from
Mount Vesuvius in 79 AD and is still in ruins today. Ash clouds, another primary impact, also
have the ability to destroy areas and cause long term damage. In Iceland, the eruption of
Eyjafjallajökull in 2010, meant 3 millimetres of ash was deposited Across the landscape, and
, HAZARDS 20 MARKERS
was carried into the jet stream. This resulted in ash being blown across Europe causing
European airspace to shut down and costing them £130 million each day of the eruption.
This demonstrates how primary impacts can have long term effects, economically and due to
the populations themselves, during the disruption they cause.
Tsunamis are sea waves, generated by violent eruptions, that can travel up to 700
kilometres an hour and cause long term, destructive effects. This was seen during the
eruption of Krakatoa in 1883, where tsunami’s destroyed the lives of more than 30,000
people. This extent of disruption can cause disastrous long term impacts for humans, the
built environment, and the economy. This is particularly for low income countries with high
density populations and lower construction standards and volcanic monitoring. Climate
change is a secondary impact that could be seen to cause the longest term, widespread
effects. The ejection of huge amounts of debris into the atmosphere has the ability to block
out sunlight and reduce global temperatures. Although this is only seen for the most powerful
eruptions, this can disrupt ecosystems around the world, as lack of heat and sunlight impact
growth of species. This shows the scale of long term effects at secondary volcanic impacts
can have.
Therefore impacts the primary impacts have, secondary impacts have the potential to cause
the longest term damage to life on earth. Tsunami’s and global climate change show this.
However, the economic situation of an area does affect the ability for them to manage
volcanic impacts and protect areas, therefore can change the long term effects these
volcanic eruptions may have.
‘It is possible to manage the impacts of volcanic eruptions, but the impacts cannot be
prevented’ to what extent do you agree with this view? [20 marks]
Management is somewhat possible, yet preventing the impacts of volcanic eruptions can be
a challenge to some extent. Levels of development have a significant impact on the ability of
a country to manage and prevent the impacts of volcanic eruptions, which can be seen in
Iceland, following the eruption of Eyjafjnallajokull and Haeimaey.
Volcanoes can be managed using various strategies, such as prediction, which can be
difficult. Volcanologists look to give fairly accurate timings for an eruption through monitoring
land swelling, changes in groundwater levels, changes in the chemical composition of
groundwater and gas emissions. Seismic activity can also be monitored by looking at shock
waves for the magma moving towards the surface. Studying the previous history of a
volcano is also crucial for understanding its activity. Accurate predictions allow areas
surrounding the volcano to prepare evacuation plans with a series of alert levels to warn the
public. Carefully planned evacuation strategies allow areas to manage the severity that the
impacts of volcanic eruptions have on populations. For example, residents can leave the
area before they are affected by lahars, volcanic mudflows made of melted snow and ice
combined with volcanic ash that travels up to 700km per hour. This can prevent loss of life,
in an area, yet doesn’t prevent the volcanic impacts from occurring and causing detrimental
effects for the built environment and the economy of the area.
There have been some methods developed in order to prevent the impacts of volcanic
eruptions, such as lava flows. During the eruption of Haeimaey in Iceland, the inhabitants
diverted the lava flow by pouring sea water on the front, so that it solidified. This prevented
the lava flow from causing destruction in the area of Iceland, demonstrating that some
impacts of volcanic eruptions can be prevented. Whilst Mt Etna in Sicily was erupting, the
population dug trenches and dropped blocks into lava streams and used explosives. This
allowed the area to slow and sometimes divert lava flow, preventing some of the impacts
that would have occurred in the area. Studying the nature of eruptions also makes it possible
to see areas at greatest risk of volcanic hazards. Land use planning strategies can then be
implemented to avoid construction of economically important infrastructure, which would be
at risk of the impacts from volcanic eruptions. This prevents the impacts of volcanic hazards
, HAZARDS 20 MARKERS
from reaching populations, therefore minimising the damage in the area. Therefore the
impacts of volcanic eruptions can be prevented to some extent.
However, these strategies do not completely prevent all impacts resulting from volcanic
eruptions, such as ash clouds during the eruption of Eyjafjnallajokull. The majority of the
Icelandic volcano was covered in ice caps feeding glaciers, therefore during the eruption, the
ice melted resulting in flooding and the development of large ash clouds. As magma hit the
ice it cooled, forming glass like material which turned into tiny particles as explosions of gas
in the main vent occurred. As ash was carried by the volcano, it dispersed into the
atmosphere and endangered the engines of aircraft. This cost airline companies £130 million
each day of the eruption. This could not have been stopped by the community, showing that
some of the more severe impacts of eruptions cannot be prevented. Prevention is also
limited in areas with low economic development, as they do not have the financial ability to
afford prevention methods such as explosives, further eluding to the fact that the impacts of
volcanic eruptions cannot be prevented.
In conclusion, the majority of impacts from volcanic eruptions cannot be prevented, and can
be managed effectively to some extent. Accurate predictions can be challenging, and levels
of economic development and location of volcanoes can also reduce the ability of
communities to completely halt the impacts of volcanic activity.
‘The severity of the impacts of the volcanic hazards experienced in a place is affected more
by the nature of plate boundaries than the level of development of the place.’ To what extent
do you agree with this view? [20 marks]
I agree to some extent that the severity of volcanic impacts is affected more by the nature of
plate boundaries than the level of development of the place. Destructive and constructive
plate margins have a significant influence on the effects a place experiences. However,
there are also other factors involved that can lead to destructive volcanoes, such as hotspots
and levels of development, which can have a major influence on the severity of impacts
experienced by a place.
The nature of plate boundaries is significant in relation to the severity of hazards, and in turn
their impacts. Volcanoes can form on both constructive and destructive plate margins. At a
destructive plate boundary, the dense oceanic plate descends below the continental plate.
Heat from friction and the core melt the plate into magma, which then rises as plutons.
These reach the surface, forming composite, explosive volcanoes. These volcanoes can
have severe impacts on the place affected, as andesitic lava is commonly associated with
ash, tephra, pyroclastic flows, and gas emissions. These hazards can significantly impact
the area surrounding the volcano and can even have global effects as large ash clouds can
block out sunlight and contribute to climate change. The Ring of Fire is an example of
volcanoes formed at a destructive boundary, which is a region around the Pacific Ocean that
consists of 755 of the world’s volcanoes. At a constructive margin, brittle crust breaks as the
plates move apart, dropping between parallel faults to form rift valleys. This crust is thinner,
so basaltic magma forces its way upwards to form volcanoes. Shield volcanoes, which are
less explosive, are common at these types of margins. This shows that plate boundaries
effect the severity of the impacts of volcanic hazards.
Although plate boundaries are commonly where volcanoes are formed. Other areas such as
hotspots can also lead to the formation of destructive volcanoes, which can significantly
impact the level of volcanic hazards experienced by a place. Concentrations of radioactive
elements below the crust can cause hotspots to develop. These heat the mantle and cause
magma plumes to rise vertically, creating volcanic activity on the surface. An example of a
volcano formed on a hotspot is the Yellowstone volcano in the USA. If this volcano were to
erupt, it would have detrimental worldwide impacts, as its ash cloud would block out the
VOLCANOES
Analyse the role of plate margins in influencing the risk posed to people by volcanic hazards
[9 marks]
Plate margins play a significant role in influencing the risk posed to people by volcanic
hazards. Destructive and constructive margins can cause a change in the severity of
volcanic hazards. However, there are arguably other factors involved in creating a greater
level of risk to the population, such as the location of the volcano.
The nature of plate boundaries is significant in relation to the severity of hazards, and the
risks they pose to people. Volcanoes can form on both constructive and destructive plate
margins. At a destructive margin, the dense oceanic plate descends below the continental
plate. Heat from friction and the core melt the plate into magma which rises as plutons.
These reach the surface to form composite, explosive volcanoes. These volcanoes can have
severe impacts on the place they affect, as andesitic lava is associated with ash, tephra, and
pyroclastic flows, which can cause devastation to human life as well as the built environment
and the economy. These hazards can impact the area surrounding the volcano which can
have global affects as the large ash clouds can block out sunlight and contribute to climate
change. The Ring of Fire provides an example of these volcanoes, as it co sits of 755 of the
worlds volcanos, located around the Pacific Ocean. At constructive margins, the brittle crust
breaks as the plates diverge, dropping between parallel faults to form rift valleys. This crust
is thinner, so basaltic magma forces its way upwards to form volcanoes such as shield
volcanoes, which are less explosive. This demonstrates the influence of plate margins on the
risk posed to populations.
On the other hand, it could be argued that the location of a volcano plays a larger role in
influence in the risk posed to people by volcanic hazards. Eyjafjallajökull is situated on a
constructive plate margin, therefore should have less of an impact on the population, yet
other physical factors meant that there was an extremely powerful eruption in April 2010.
The volcano is situated on ice caps, therefore when the volcano erupted, the ice melted
which caused severe flooding and ash clouds. The ash was particularly damaging for the
local area, as when the magma hit the ice, it called, forming glass like material. Explosions of
gas in the main vent caused these abrasive shards to become tiny particles, which were
dispersed by the cloud and endangered engines of aircraft, costing airlines £130 million a
day each day of the eruption. This meant that the locals were unable to leave the area and
people became stranded. This shows that, although plate boundaries are important, other
physical factors like the location of the volcano are important in determining the levels of
impact.
In conclusion, although plate margins can influence volcanic hazards, location can be
argued to be a more important factor determining the risk posed to people. Eyjafjallajökull is
a clear example of this.
How far do you agree that secondary impacts of volcanic eruptions present a greater long-
term threat to people than primary impacts? [9 marks]
I agree to some extent. Primary volcanic impacts, such as pyroclastic flows an ash clouds,
have the ability to present significant long term threat to populations. However, secondary
impacts, including tsunami’s and climate change, have the ability to cause more long term
disruption, as well as wider spread effects.
Pyroclastic flows are hot, gas charged flows of gas and tephra that can travel up to 700
kilometres per hour. These flows have the power to cause mass destruction of an area, and
little can be done to intervene, for example, Pompeii was destroyed by these flows from
Mount Vesuvius in 79 AD and is still in ruins today. Ash clouds, another primary impact, also
have the ability to destroy areas and cause long term damage. In Iceland, the eruption of
Eyjafjallajökull in 2010, meant 3 millimetres of ash was deposited Across the landscape, and
, HAZARDS 20 MARKERS
was carried into the jet stream. This resulted in ash being blown across Europe causing
European airspace to shut down and costing them £130 million each day of the eruption.
This demonstrates how primary impacts can have long term effects, economically and due to
the populations themselves, during the disruption they cause.
Tsunamis are sea waves, generated by violent eruptions, that can travel up to 700
kilometres an hour and cause long term, destructive effects. This was seen during the
eruption of Krakatoa in 1883, where tsunami’s destroyed the lives of more than 30,000
people. This extent of disruption can cause disastrous long term impacts for humans, the
built environment, and the economy. This is particularly for low income countries with high
density populations and lower construction standards and volcanic monitoring. Climate
change is a secondary impact that could be seen to cause the longest term, widespread
effects. The ejection of huge amounts of debris into the atmosphere has the ability to block
out sunlight and reduce global temperatures. Although this is only seen for the most powerful
eruptions, this can disrupt ecosystems around the world, as lack of heat and sunlight impact
growth of species. This shows the scale of long term effects at secondary volcanic impacts
can have.
Therefore impacts the primary impacts have, secondary impacts have the potential to cause
the longest term damage to life on earth. Tsunami’s and global climate change show this.
However, the economic situation of an area does affect the ability for them to manage
volcanic impacts and protect areas, therefore can change the long term effects these
volcanic eruptions may have.
‘It is possible to manage the impacts of volcanic eruptions, but the impacts cannot be
prevented’ to what extent do you agree with this view? [20 marks]
Management is somewhat possible, yet preventing the impacts of volcanic eruptions can be
a challenge to some extent. Levels of development have a significant impact on the ability of
a country to manage and prevent the impacts of volcanic eruptions, which can be seen in
Iceland, following the eruption of Eyjafjnallajokull and Haeimaey.
Volcanoes can be managed using various strategies, such as prediction, which can be
difficult. Volcanologists look to give fairly accurate timings for an eruption through monitoring
land swelling, changes in groundwater levels, changes in the chemical composition of
groundwater and gas emissions. Seismic activity can also be monitored by looking at shock
waves for the magma moving towards the surface. Studying the previous history of a
volcano is also crucial for understanding its activity. Accurate predictions allow areas
surrounding the volcano to prepare evacuation plans with a series of alert levels to warn the
public. Carefully planned evacuation strategies allow areas to manage the severity that the
impacts of volcanic eruptions have on populations. For example, residents can leave the
area before they are affected by lahars, volcanic mudflows made of melted snow and ice
combined with volcanic ash that travels up to 700km per hour. This can prevent loss of life,
in an area, yet doesn’t prevent the volcanic impacts from occurring and causing detrimental
effects for the built environment and the economy of the area.
There have been some methods developed in order to prevent the impacts of volcanic
eruptions, such as lava flows. During the eruption of Haeimaey in Iceland, the inhabitants
diverted the lava flow by pouring sea water on the front, so that it solidified. This prevented
the lava flow from causing destruction in the area of Iceland, demonstrating that some
impacts of volcanic eruptions can be prevented. Whilst Mt Etna in Sicily was erupting, the
population dug trenches and dropped blocks into lava streams and used explosives. This
allowed the area to slow and sometimes divert lava flow, preventing some of the impacts
that would have occurred in the area. Studying the nature of eruptions also makes it possible
to see areas at greatest risk of volcanic hazards. Land use planning strategies can then be
implemented to avoid construction of economically important infrastructure, which would be
at risk of the impacts from volcanic eruptions. This prevents the impacts of volcanic hazards
, HAZARDS 20 MARKERS
from reaching populations, therefore minimising the damage in the area. Therefore the
impacts of volcanic eruptions can be prevented to some extent.
However, these strategies do not completely prevent all impacts resulting from volcanic
eruptions, such as ash clouds during the eruption of Eyjafjnallajokull. The majority of the
Icelandic volcano was covered in ice caps feeding glaciers, therefore during the eruption, the
ice melted resulting in flooding and the development of large ash clouds. As magma hit the
ice it cooled, forming glass like material which turned into tiny particles as explosions of gas
in the main vent occurred. As ash was carried by the volcano, it dispersed into the
atmosphere and endangered the engines of aircraft. This cost airline companies £130 million
each day of the eruption. This could not have been stopped by the community, showing that
some of the more severe impacts of eruptions cannot be prevented. Prevention is also
limited in areas with low economic development, as they do not have the financial ability to
afford prevention methods such as explosives, further eluding to the fact that the impacts of
volcanic eruptions cannot be prevented.
In conclusion, the majority of impacts from volcanic eruptions cannot be prevented, and can
be managed effectively to some extent. Accurate predictions can be challenging, and levels
of economic development and location of volcanoes can also reduce the ability of
communities to completely halt the impacts of volcanic activity.
‘The severity of the impacts of the volcanic hazards experienced in a place is affected more
by the nature of plate boundaries than the level of development of the place.’ To what extent
do you agree with this view? [20 marks]
I agree to some extent that the severity of volcanic impacts is affected more by the nature of
plate boundaries than the level of development of the place. Destructive and constructive
plate margins have a significant influence on the effects a place experiences. However,
there are also other factors involved that can lead to destructive volcanoes, such as hotspots
and levels of development, which can have a major influence on the severity of impacts
experienced by a place.
The nature of plate boundaries is significant in relation to the severity of hazards, and in turn
their impacts. Volcanoes can form on both constructive and destructive plate margins. At a
destructive plate boundary, the dense oceanic plate descends below the continental plate.
Heat from friction and the core melt the plate into magma, which then rises as plutons.
These reach the surface, forming composite, explosive volcanoes. These volcanoes can
have severe impacts on the place affected, as andesitic lava is commonly associated with
ash, tephra, pyroclastic flows, and gas emissions. These hazards can significantly impact
the area surrounding the volcano and can even have global effects as large ash clouds can
block out sunlight and contribute to climate change. The Ring of Fire is an example of
volcanoes formed at a destructive boundary, which is a region around the Pacific Ocean that
consists of 755 of the world’s volcanoes. At a constructive margin, brittle crust breaks as the
plates move apart, dropping between parallel faults to form rift valleys. This crust is thinner,
so basaltic magma forces its way upwards to form volcanoes. Shield volcanoes, which are
less explosive, are common at these types of margins. This shows that plate boundaries
effect the severity of the impacts of volcanic hazards.
Although plate boundaries are commonly where volcanoes are formed. Other areas such as
hotspots can also lead to the formation of destructive volcanoes, which can significantly
impact the level of volcanic hazards experienced by a place. Concentrations of radioactive
elements below the crust can cause hotspots to develop. These heat the mantle and cause
magma plumes to rise vertically, creating volcanic activity on the surface. An example of a
volcano formed on a hotspot is the Yellowstone volcano in the USA. If this volcano were to
erupt, it would have detrimental worldwide impacts, as its ash cloud would block out the
