To what extent do you agree that seismic events will always generate more widespread and
severe impacts than volcanic events? [9]
On the one hand, it can be said that seismic hazards generate more widespread and severe impacts
than volcanic events. For instance, this may be due to the fact that many seismic hazards such as
earthquakes cause severe impacts in terms of deaths and impacting buildings due the ground
rupturing element of the hazard. Surface waves, which occur during seismic hazards are the most
destructive waves, but long and slow. Raleigh waves create a rolling, up and down motion confined
to the vertical plane in direction of propagation elliptical. However, the other surface wave, the Love
waves have motion which is transverse to the direction of propagation (side to side motion) and love
waves cause the most destruction. The extent to which seismic hazards generate more widespread
and severe impacts can also be seen evident in the Christchurch earthquake of 2011. For example,
185 deaths were recorded, along with widespread impacts such as over 1,000 city buildings were
damaged and over 100,000 suburb homes needed repairs to some extent. In addition, over 160,000
homes lacked access to flushing toilets due to damaged sewage pipes therefore causing hygiene and
sanitation problems. The factors outlined above clearly highlight the severity of seismic hazards and
the widespread impact they can have.
Another seismic event is a tsunami, the boxing Day tsunami in the Indonesia area further
supports the argument that seismic events can have widespread and severe impacts. The 9.2
magnitude earthquake, with a 10km focus caused 230,000 deaths across 14 countries and eight
people were killed in South Africa over 8000km away. This clearly shows how seismic hazards can
have widespread impacts as well as severe localised ones.
On the other hand, it could be argued that volcanoes have more severe and widespread
impacts. For example, the Eyjafjallajökull eruption caused widespread issues. The ash cloud
produced by the volcanic hazard reached a height of 22,000 feet, thus causing 10 million airline
passengers to be affected and many stranded abroad. The severity of the volcanic hazard seemed to
occur in economic terms as airlines were losing an estimated $200million each day from flights being
unable to take off. In addition, the this the widespread nature of the eruption caused Kenya to lose
£3.5 million in exports and 50,000 farmers became temporarily unemployed as agricultural produce
could not be flown to Europe. Furthermore, the occurrence of pyroclastic flow or nuees ardents can
cause widespread and severe impacts. These are hot rock fragments, lava particles ash and hot
gases. They are linked with subduction zone volcanoes, and the flow moves very quickly from its
source, at speeds up to 700km/h at temp of 820 degrees reaching 120km from the volcano.
However, these extremely severe effects occur only usually at violent stato volcanoes at destructive
margins, therefore reducing the regularity of this severe and widespread effect.
In conclusion it is difficult to evaluate the extent to which natural event has more severe and
widespread effects as each event is different. The management is also an extremely factor in
mitigating against the impact of such hazards, thus reducing the impact and severity. The ash cloud
associated with volcanic eruptions can cause more widespread effects than seismic events which
tend to cause more local but severe damage. However overall, it can be said the seismic events can
cause not only the most severe hazards but also most widespread as seen in the Boxing Day Tsunami
of 2004.
“The Impact of seismic hazards is influenced by the level of development of the places affected.” To
what extent do you agree with this view [20]
Seismic hazards are the intrinsic natural occurrence of earthquakes and the resulting ground motion
and other effects. Human factors such as development can be extremely important, as seen in
recent events such as Haiti and the largely well-developed Christchurch earthquake. However,
physical factors also have importance. Plate boundaries more specifically the type of boundary can
affect the impact it has due the differing nature of collision. For example, destructive and
severe impacts than volcanic events? [9]
On the one hand, it can be said that seismic hazards generate more widespread and severe impacts
than volcanic events. For instance, this may be due to the fact that many seismic hazards such as
earthquakes cause severe impacts in terms of deaths and impacting buildings due the ground
rupturing element of the hazard. Surface waves, which occur during seismic hazards are the most
destructive waves, but long and slow. Raleigh waves create a rolling, up and down motion confined
to the vertical plane in direction of propagation elliptical. However, the other surface wave, the Love
waves have motion which is transverse to the direction of propagation (side to side motion) and love
waves cause the most destruction. The extent to which seismic hazards generate more widespread
and severe impacts can also be seen evident in the Christchurch earthquake of 2011. For example,
185 deaths were recorded, along with widespread impacts such as over 1,000 city buildings were
damaged and over 100,000 suburb homes needed repairs to some extent. In addition, over 160,000
homes lacked access to flushing toilets due to damaged sewage pipes therefore causing hygiene and
sanitation problems. The factors outlined above clearly highlight the severity of seismic hazards and
the widespread impact they can have.
Another seismic event is a tsunami, the boxing Day tsunami in the Indonesia area further
supports the argument that seismic events can have widespread and severe impacts. The 9.2
magnitude earthquake, with a 10km focus caused 230,000 deaths across 14 countries and eight
people were killed in South Africa over 8000km away. This clearly shows how seismic hazards can
have widespread impacts as well as severe localised ones.
On the other hand, it could be argued that volcanoes have more severe and widespread
impacts. For example, the Eyjafjallajökull eruption caused widespread issues. The ash cloud
produced by the volcanic hazard reached a height of 22,000 feet, thus causing 10 million airline
passengers to be affected and many stranded abroad. The severity of the volcanic hazard seemed to
occur in economic terms as airlines were losing an estimated $200million each day from flights being
unable to take off. In addition, the this the widespread nature of the eruption caused Kenya to lose
£3.5 million in exports and 50,000 farmers became temporarily unemployed as agricultural produce
could not be flown to Europe. Furthermore, the occurrence of pyroclastic flow or nuees ardents can
cause widespread and severe impacts. These are hot rock fragments, lava particles ash and hot
gases. They are linked with subduction zone volcanoes, and the flow moves very quickly from its
source, at speeds up to 700km/h at temp of 820 degrees reaching 120km from the volcano.
However, these extremely severe effects occur only usually at violent stato volcanoes at destructive
margins, therefore reducing the regularity of this severe and widespread effect.
In conclusion it is difficult to evaluate the extent to which natural event has more severe and
widespread effects as each event is different. The management is also an extremely factor in
mitigating against the impact of such hazards, thus reducing the impact and severity. The ash cloud
associated with volcanic eruptions can cause more widespread effects than seismic events which
tend to cause more local but severe damage. However overall, it can be said the seismic events can
cause not only the most severe hazards but also most widespread as seen in the Boxing Day Tsunami
of 2004.
“The Impact of seismic hazards is influenced by the level of development of the places affected.” To
what extent do you agree with this view [20]
Seismic hazards are the intrinsic natural occurrence of earthquakes and the resulting ground motion
and other effects. Human factors such as development can be extremely important, as seen in
recent events such as Haiti and the largely well-developed Christchurch earthquake. However,
physical factors also have importance. Plate boundaries more specifically the type of boundary can
affect the impact it has due the differing nature of collision. For example, destructive and
