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EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Location – place where something can be found
Define the terms:
(a) location
(b) characteristics
(c) distribution
Characteristics – the main features of the item
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Describe the global distribution of earthquakes
and volcanoes.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
What is the structure of the Earth?
Distribution – the pattern of where something is
on Earth (look for trends and anomalies – do not
fit trend)
- Both earthquakes & volcanoes occur in long narrow
bands - often following the edge of continents (e.g.
West Coast of North & South America)
- Largest band of volcanoes are found along the
Pacific Ring of Fire (around the Pacific Ocean)
- Earthquakes and Volcanoes are also found together
in bands in the middle of Oceans (e.g. Mid-Atlantic
Ridge)
- NOT all follow the same pattern:
some volcanoes are found in isolated clusters - e.g.
Hawaiian Islands - middle of Pacific Plate) – known as
a hot spot;
some earthquakes occur away from plate
boundaries – intraplate earthquakes – e.g. Gujurat,
India earthquake 2001.
Answer(s)
The Earth is made up of four distinct layers:
1. The inner core is in the centre and is the
hottest part of the Earth. It is solid and made
up of iron and nickel with temperatures of
up to 5,500°C.
2. The outer core is the layer surrounding the
inner core but is liquid.
3. The mantle is the widest section of the
Earth. It has a thickness of approximately
2,900 km. The mantle is made up of semimolten rock called magma. In the upper
parts of the mantle the rock is hard, but
lower down the rock is soft and beginning to
melt.
4. The crust is the solid outer layer of the earth
which is broken into 7 large plates. It is a thin
layer between 0-70 kms thick. The crust is
the solid rock layer upon which we live.
There are two different types of crust: continental
crust, which carries land, and oceanic crust, which
carries water.
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Oceanic crust is 5-10km thick (Continental 25-100km)
Give three differences between oceanic and
continental crust.
Oceanic crust is denser (heavier) than continental
crust
Oceanic crust is constantly renewed and destroyed
(continental is permanent and cannot be destroyed.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
What are convection currents?
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
What are hotspots?
Answer(s)
Convection currents
– a movement of
heated material
(magma) up through
the mantle from the
Earth’s core to the
crust.
As the magma cools it
sinks down to be
reheated.
Answer(s)
A hotspot is a plume (column) of
magma (hot molten material) rising
from the mantle. Usually occur
under oceans.
This magma is lighter than the
surroundings and rises - erupting at
the surface where the crust is thin, creating a volcano
(and eventually a volcanic island)
They are fixed within the mantle & as the crust moves
over the top - a chain of volcanic islands is left behind
(e.g. Hawaii)
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
What are the different types of plate
boundaries?
Divergent (constructive) plate boundary –
the plates move away from each other and
create the crust.
Convergent (destructive) plate boundary –
the plates move towards each other and
destroy the crust
Conservative plate boundary – the plates
move past each other – crust is not made or
destroyed.
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
What type of boundary is shown in the diagram
below? - Outline what happens here.
Answer(s)
Convergent (destructive) plate boundary where
an oceanic (e.g. Nazca) and continental (e.g.
South American) plate move towards each
other due to convection currents.
- Denser (heavier) oceanic crust is subducted
below the continental plate, forming a deep
ocean trench
- Heat from the mantle & friction between the
plates causes the oceanic plate to be destroyed
- As the plate melts, magma forms and due to
the pressure and the heat is forced to rise to the
surface
- Magma erupts at the surface as lava, forming a
composite cone volcano
- Fold mountains (e.g. Andes) are created due to
the impact of collision (earthquakes may occur)
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
A - Subduction Zone
Name the characteristic features at A, B, C and D
B - Oceanic Trench
C - Island Arc
D - Volcano
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain what happens at a convergent plate
boundary where two oceanic plates meet.
Answer(s)
- Plates move towards each other due to
convection currents.
- Cooler and denser (heavier) oceanic crust is
subducted, forming a deep ocean trench
- As the plate descends it deforms, creating
frequent earthquakes – known as the Benioff
zone.
- Heat from the mantle & friction between the
plates causes the denser oceanic plate to be
destroyed
- As the plate melts, magma forms and due to
the pressure and the heat is forced to rise to the
surface
- Magma erupts at the surface as lava, forming a
volcano
- E.g. Philippine Plate moving west & subducting
under the Eurasian plate (forms the Ryuku Islands - nr
Japan)
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the formation of fold mountains.
Answer(s)
Fold mountains form at continental-continental
convergent boundaries (can also occur at
oceanic-continental).
- At these boundaries as the two plates meet,
the force of the collision causes folding and
faulting to occur
- This results in uplift of rock and sediment
squeezed during the collision.
- The result is fold mountains such as the
Himalayas (Indian plate colliding with Eurasian)
- There are no volcanoes as the crust is not being
melted and subducted
- Earthquakes occur due to the continued impact
of the collision.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain the processes at a divergent plate
boundary
Answer(s)
- Two plates move away from each other due to
convection currents
- As the plate move apart, pressure causes the
crustal rocks to fracture and a gap and ridge
(mid-oceanic ridge) form – e.g. Mid-Atlantic
ridge
- Magma rises to fill the gap, volcanoes form and
new crust is created (usually found under the
ocean, this is known as sea floor spreading).
- As magma builds up, volcanic islands form
above the surface of the ocean (e.g. Surtsey,
Iceland)
- Often have earthquakes associated with these
boundaries.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Name the features found at an oceanic-oceanic
convergent boundary.
1. Oceanic Trench
2. Subduction Zone
3. Volcanic Islands
4. Island arc
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Name the features found at an oceaniccontinental convergent boundary.
1. Oceanic Trench
2. Subduction Zone
3. Fold Mountains
4. Volcanoes
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain what happens at a conservative
(transform) plate boundary
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Also known as passive plate boundaries.
- Two plates slide past each other, without
creating or destroying any land.
- As they move past each other they often get
stuck, building up great pressure until finally
they jolt past each other. This sudden movement
is what causes violent and frequent earthquakes.
There is no subduction = no volcanoes.
- The best-known example of a conservative
plate boundary is the San Andreas Fault, where
the North American (1cm per year) and Pacific
(6cm per year) plates are actually moving in the
same direction, but at different speeds.
Answer(s)
Fold Mountains - Himalayas or Andes
Name an example of:
- Fold Mountains
- Oceanic Ridge
- Islands created by a hotspot
- Convergent Boundary
- Transform Fault
Oceanic Ridge - Mid-Atlantic Ridge
Islands created by a hotspot - Hawaiian Islands
Convergent Boundary - Nazca and South
American Plates meeting
Transform Fault - San Andreas Fault (California) also known as a conservative boundary
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Define the following key terms...
1. Epicentre
2 Focus
3. Magnitude
Answer(s)
1. Epicentre - this is the point on the surface
directly above the focus of an earthquake - the
most damage to buildings and infrastructure
(e.g. roads, electricity) often occur here
2. Focus - this is the point underground where
the earthquake starts - it is here where the
greatest release of energy occurs – shock waves
move out from this point
3. Magnitude - the strength of an earthquake,
reflecting the amount of energy released.
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Give four differences between the Mercalli scale
and the Richter Scale.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the economic reasons for people
continuing to live in areas prone to volcanic
activity.
Exam tip: You must know a range of placespecific examples
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the social reasons for people continuing
to live in areas prone to volcanic activity.
Exam tip: You must know a range of placespecific examples
Answer(s)
1. Mercalli scale measure damage caused by
an earthquake whereas the Richter scale
measures the magnitude
2. Mercalli scale measurements are based
on observations of damage to buildings
whereas the Richter scale is based on
scientific measurements from a
seismometer
3. Mercalli scale is subjective(based on
opinion) - the Richter scale is quantitative
(objective) using a logarithmic scale = each
level is 10x greater than previous one.
4. The Mercalli scale is not useful in
uninhabited areas (few visible effects).
Richter scale can be used to measure
earthquake vibrations anywhere (if
seismometer in place).
Answer(s)
- Fertile soils - provide rich opportunities for
growing crops to be sold (e.g. Coffee grown
on the slopes of volcanoes in Columbia).
- Important source of cheap geothermal
energy e.g. Iceland 28% of electricity from
geothermal sources.
Answer(s)
Perception – inertia – believe there is very
little risk of a volcano happening e.g. Mt St
Helens (1980) many refused to evacuate as
had been dormant for 123 years.
Poverty in LICs – many people cannot afford
to move e.g. Mt Merapi (Indonesia) is one of
the world’s most active volcanoes though
70,000 people live in vicinity.
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the environmental reasons for people
continuing to live in areas prone to volcanic
activity.
Exam tip: You must know a range of
place-specific examples
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the economic reasons for people
continuing to live in areas prone to earthquake
activity.
Exam tip: You must know a range of
place-specific examples
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Outline the social reasons for people continuing
to live in areas prone to earthquake activity.
Exam tip: You must know a range of placespecific examples
Answer(s)
The area around the volcano is very scenic and many
tourists visit e.g.:
- Iceland with attractions like Blue Lagoon, Strokkur
Geysir - provides 5000 jobs and accounts for 5% of
Iceland's earnings & - - Indonesia: Popular active volcanoes are the 2,329metre (7,641 ft) high Mount Bromo in the East Java
province with its scenic volcanic desert around the
crater
Answer(s)
Many e/q prone areas are also popular tourist areas therefore people prepared to take the risk because of
jobs e.g. Iceland – many jobs related to showing
tourists the earthquake areas.
People have jobs in the mining industry in e/q areas
e.g. Copper mine in Chile. In 2007, 2 people killed in
mine during an earthquake, though local people think
risk is acceptable because they have a job.
Answer(s)
- Technology in HICs- increased confidence due
to earthquake proof buildings and disaster
management plans in place e.g reinforced
foundations / counterweights such as those in
Japan and California (e.g. Transamerica building San Francisco) - also advanced rescue equipment
and detailed disaster plans in place.
- Perception in LICs that there is little risk inertia
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Answer(s)
Outline the environmental reasons for people
continuing to live in areas prone to earthquake
activity.
Some earthquake areas are very scenic and have
been developed for wealthy people e.g. Malibu,
a very expensive coastal resort, has developed
on the California coast of the USA.
Exam tip: You must know a range of placespecific examples
Most of the country is tectonically active (e.g.
Japan)
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain how the effects of earthquakes can be
reduced through prediction and prevention
Exam tip: You must know a range of placespecific examples
Answer(s)
Prediction:
Forecasting:
- Seismometers can measure movements and may
predict when likely to take place e.g. USGS post
earthquake activity / stresses within one minute on
their website.
- Study of stress in geology (rock type). e.g. Los
Angeles basin (prone to earthquakes) made of coastal
sediment = very weak.
- Hazard mapping using historical data.
Note: Prediction = very difficult, as earthquake is a
sudden movement.
Prevention:
Building design and defence – earthquake proof new
and retrofitting older buildings to make them safe –
reinforced foundations; automatic shutters on
windows; interlocking framework. E.g. San Francisco
airport has columns standing on 1.5 metre ball
bearings which allow the building to sway with an
earthquake.
Education and planning – Japan has an annual
earthquake practice drill such as ‘duck, cover and
hold on’ on 1st Sept for schools and businesses based
on a 7.3 magnitude scenario. In the USA, (F)ederal
(E)mergency (M)anagement (A)gency provides packs
on how to prepare for earthquakes as well as
information on their website.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain how the effects of volcanoes can be
reduced through prediction and prevention
Exam tip: You must know a range of placespecific examples
Answer(s)
Prediction:
Forecasting:
- Eruption of Mount St. Helens (May 1980) was
predicted due to the movement of tiltmeters placed
on its slopes.
- Gases are monitored e.g. Mt Pinatubo predicted due
to change in gases (SO2) coming out of the volcano
- Remote sensing: infrared satellite images record
changes in the shape of the volcano
Prevention:
Building design and defence – lava flows cooled with
water slow movement; diversion channels can also be
built around villages.
Mt Etna (Sicily) earth walls have been built to divert
lava away from a cable car used by thousands of
tourists every year.
Education and planning – Locals educated in how to
look for signs of a likely eruption e.g. Sicily, locals are
taught to look for changes in the consistency of the
lava.
EMS Geography GCSE Revision FLASH CARDS:
Unit 2 – Tectonic Landscapes
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain the causes of a volcanic eruption you
have studied.
Answer(s)
Case study: Chances Peak eruption, Montserrat
(1997)
- Montserrat is a volcanic island on a destructive
plate boundary.
- The two plates that meet at this plate boundary
are the North American plate which is subducted
under the Caribbean plate.
Exam tip: You must know a range of placespecific points
- Produced a huge ash cloud which covered the
southern part of the island. Pyroclastic flows of
hot rock and ash were also thrown out of the
volcano.
EMS Geography GCSE Revision: Question(s)
TECTONIC LANDSCAPES
Explain the effects of a volcanic eruption you
have studied on people and the environment.
Exam tip: You must know a range of placespecific points
Answer(s)
Case study: Chances Peak eruption, Montserrat
(1997)
Effects on People:
- 19 people killed by the pyroclastic flows.
- Villages of Farm and Trant were completely
buried by ash flow.
- 150 homes destroyed.
- Transport routes destroyed: Bramble airport
was closed which disrupted international aid
which was coming to help the islanders.
Effects on the environment:
- 4km2 covered by ash and rock.
- Pyroclastic flows caused the river Belham to
flood.
- Pyroclastic flows removed all vegetation in the
south of the island including the ridges around
Farrell’s Yard.