This document consists of 76 questions related to the AQA A level Geography specification. It covers the Water and Carbon Cycle; a topic that features in Paper 1. Eleven questions are answered in detail and can be used as model answers for students. They are written by an A* predicted student and marked, with all answers receiving full marks. A bank of 69 additional questions is listed below the document
HAZARDS
Analyse the role of plate margin type in influencing the risk
posed to people by volcanic hazards (9 marks)
There are three types of plate margins: constructive (involves two plates moving away from each
other), destructive (involves two plates colliding with each other) and conservative (involves two
plates sliding past each other). However, it is only at constructive and destructive boundaries where
volcanic activity occurs.
At constructive plate boundaries, basaltic lava is formed. Due to its low silica content, it has a low
viscosity and so can flow quickly, extending tens of kilometres from an erupting vent, resulting in
relatively gentle but frequent eruptions. Having a low viscosity also means basaltic lava is associated
with pyroclastic flows and ash fallout. Rapid lava flows at constructive plate margins pose a very high
risk to people because they travel faster so they cover a larger distance than slower flows, meaning
there would be higher levels of destruction to the surrounding land and infrastructure. When basalt
lava flows are confined within a channel or lava tube on a steep slope, the main body of the flow can
reach velocities over 30 km/h, reducing the amount of time for nearby people to evacuate and
therefore posing a higher risk.
At destructive plate boundaries, andesitic lava is formed. Due to its high viscosity, andesitic lava
flows are slower (travelling at only a few kilometres per hour) and therefore cover shorter distances.
Their eruptions may be less frequent than basaltic ones, but they are more violent because of gas
build up. Andesite lava can generate strong explosive eruptions to form fast-flowing pyroclastic
flows, Pyroclastic flows vary considerably in size and speed, but even relatively small flows that move
less than 5 km from a volcano can destroy buildings, forests, and farmland. On the margins of
pyroclastic flows, death and serious injury to people and animals may result from burns and
inhalation of hot ash and gases, however deaths caused directly by andesite lava are uncommon
because it moves slowly enough for people to evacuate. A well-resourced nation would be at a lower
risk because they have higher levels of preparedness (e.g. advanced equipment, a predetermined
procedure. Etc) and therefore can mitigate against this impact effectively.
In conclusion, the risks associated with different types of plate boundaries can pose varying levels of
risks to people, depending on the type of plate margins and whether volcanic activity can occur
there or not, type of lava erupted and its viscosity and how it travels (through a confined channel or
as a broad sheet).
Assess the importance of governance in the successful
management of tectonic hazards (20 marks)
A sudden volcanic eruption of Mt Ontake occurred on Saturday 27th September 2014 on the main
island of Honshu, Japan. It was thought to be dormant (an active volcano is not erupting but is
supposed to erupt again) until 1979, where it underwent a series of minor eruptions. These small
eruptions were meant to signal an impending eruption. However, this was not detected, and Mt
Ontake erupted without warning, causing chaos and danger amongst the tourists, hikers and
climbers that the mountain is popular with.
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Japan is a prosperous, well developed nation meaning it has the available resources for well
communicated contingency planning to take place. The country has the capability of providing the
necessary education for residents to learn how to act if a tectonic hazard occurs. This can be as
simple as providing volcanic eruption/earthquake preparation checklists, emergency kits, practising
evacuation drills and conducting natural disaster related lessons in schools. Furthermore, with a
stable government Japan can encourage builders and archaeologists to construct natural disaster
proof infrastructure that can withstand ground shaking-providing enough time for people in the
building to evacuate safely. Japan’s high levels of preparedness allowed its residents, infrastructure
and land to be affected at a significantly reduced level.
On the other hand, a tectonic hazard is very hard to predict, making governments who are facing
potential future earthquakes struggle to make successful predictions and therefore a successful
management plan. Mt Ontake was a false negative - where no prediction was made for a volcano
that occurs. This can be deemed as very problematic because it can incite fear and chaos to a
population that is not warned from any precursory events, which could result in people migrating to
a safer place or continuing to act in a less rational manner. Mt Ontake was extremely difficult to
predict despite Japan’s ability to access advanced equipment (e.g. seismographs, seismometers,
instruments that detect and measure volcanic gases. Etc), as there were no visible signs that an
eruption was about to occur, such as microquakes before the tremor, bulging of the ground and
decreasing radon gas concentration. This makes prevention almost impossible so any pre-prepared
planning (even if it were done with the latest advanced technology) cannot be reliable meaning the
importance of governance in the successful management of tectonic hazards is quite low due to the
high level of unpredictability.
It was very clear that Japan was well prepared and had a preconceived plan as there were around
1000 Japanese rescue workers- police, firefighters and military personnel, who set out to search the
mountain’s peak where the affected victims of the eruption were most likely to be situated. This
immediate disaster recovery approach reduced deaths and injury and in turn alleviated the pressure
of hospitals and paramedics to provide emergency medical care. It also ensured trust and
reassurance to the victims that any future natural disasters that Japan may face will be managed in
the same organized manner ((presumably even more due to advanced technology and the continual
reviewing of previous disasters) and uniformed manner like this one. Furthermore, the immediate
response also reduced economic losses as the victims were not severely injured to the extent where
they could not continue working in their current jobs. This ensured that jobs were not being lost and
Japan’s economy was not directly affected by these victims, ultimately saving more money which
could go to better research projects that can make successful predictions and advanced eruptiondetectable technology. Therefore, governance contributes greatly to the successful management of
tectonic hazards.
In conclusion the importance of governance in the successful management of tectonic hazards vary
greatly and depend on how well resourced the country is, it’s levels of preparedness and the
effectiveness of the responses in the short and long term.
To what extent can the level of earthquake prediction available
today help governments who are faced with potential future
earthquakes? (9 marks)
Similarly, to volcanic eruptions, the frequency and regularity of earthquakes show no predictably.
However, continually reviewing and analysing contingency planning allows a nation to be prepared
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