Volcanic eruptions can be monitored and potentially predicted using various methods. Earthquake activity, ground deformation measured by tiltmeters and GPS, changes in magma temperature, and gas emissions are monitored in real-time. Seismometers are also used to analyze earthquake waves. By studying patterns of past eruptions, including the timing of flows and gaps between events, volcanologists aim to improve predictions. However, volcanic eruptions often remain unpredictable.

1. Paper 1 revision
Yr 9 requests

2. Hydrological cycle

4. Hydrograph
Baseflow = the normal day
to day discharge of the river
The result of groundwater
seeping into the river
channel.
The rising limb of the
hydrograph = the rapid
increase in discharge
resulting from rainfall
causing surface runoff and
then later throughflow
The time difference between the peak of the
rain event and the peak discharge is known as
the lag time or basin lag
The falling limb (=
recession limb) is when
discharge decreases and
the river’s level falls. It is
mainly throughflow
which is making up the
river water.
Peak discharge occurs when the river reaches
its highest level

5. 2010Q5c(i) 3 marks
5c(ii) suggest why the hydrographs are different (4 marks)

6. Which part of the
hydrological cycle is shown
here?
Where is the soil able to
absorb most rainfall? Why?

7. CAUSES EFFECTS STRATEGIES
PHYSICAL HUMAN
•v.heavy relief rain
•High, steep land –
rapid run off
•Series – steep v
shaped tributary
valleys-fast flowing
•V. wide flat
floodplain
•River meanders
•Farmland drained
•Urbanisation on
floodplain
•Massive flooding –
towns, farmland
•Homes
•Businesses
•Crops
•Possessions
•Transport
•Drinking water
•Gas, electricity
LOST
•Dredging ? Costly,
unsightly
•Flood walls,
embankments ?
•Allow farmland to
flood ?
•Objections –
farmers, too costly
•Temporary aluminium
planks ?

8. What causes flooding?
Impermeable rock
deforestation
Arable farming
Building on floodplains
Heavy rainfall
Lots of tributaries
Marshy areas Very
wet soil
Hard dry soil
steep slopes

9. Physical causes of
floods
Cause .... Because..... So....
In steep valleys Water runs down steep slopes
quickly because water flow
faster on steeper slopes
Increases discharge quickly
which causes flood
Heavy rain falling over a
long period of time
Soil becomes saturated Water table rises, no more
rain can infiltrate, causes
more run off to rivers which
fill and overflow their banks
Heavy rain falling over a
short period of time
If intense rain falls on hard,
baked ground then water flows
quickly to rivers
Causes flash floods as river
levels rise rapidly
Snow melt in spring Lots of water going into river in
short time
Increases discharge is too
much for it to hold
Impermeable rocks Water cannot percolate
through the rocks
Soils quickly become
saturated and this increases
overland flow

10. Human causes of floods ....
Cause .... Because .... So....
Urban area Tarmac and concrete is
impermeable
Increases surface
run off so more
water flows into the
river
Deforestation If trees are removed
there is nothing to
break the rain hitting
the ground which may
cause soil erosion
Eroded soil is
washed into channel
causing flooding

11. Flood protection
*Dams
hold back flood
waters
*reservoirs
store floodwater
*straighten
channels
Increases speed of
flow
*Dredging
Makes channel deeper so
can hold more water
*levees and embankments
Prevents river from
overflowing
*land use zoning
Restricts development to
uses unaffected by flooding
*afforestation
Increases
interception etc,
reduces run off

12. Study Figure 9, which shows a plan for flood plain
zoning
Flood plain zoning is a ‘soft management strategy’.
What does this mean? (1mark)
Using Figure 9, describe the flood plain zoning and explain why strategies such
as this are sustainable. (6marks)
AQA A 2005

13. Strategy How does it work? Advantages disadvantages
Dams hold back flood
waters
River flow can be
controlled
Reservoirs used for
HEP or leisure
Costly
unsightly
Straightening
channel
Increases speed of
flow
Flooding risk
passed
downstream
Build levees Prevents river from
overflowing
Effectively
increases channel
capacity before
overflowing
Can provide
walkways, leisure
routes
Costly
unsightly
Hard engineering strategies summary

14. RIVERS
•Traction
•Saltation
•Suspension
•Solution
•Abrasion
•Attrition
•Solution
•Hydraulic action
•Vertical erosion
•Weathering
valley sides
•Interlocking
spurs -winding •Hard + soft
rock
•Plunge pool
•Overhang
•Gorge
•Fast flow
•Erosion
•River cliff
•Deep water
•Slow flow
•Deposition
•Slip off slope
•Shallow
water
•Alluvium
•Levees
•Oxbow lakes
•Flat floor
•Gentle sides
•Heavy rain
•Rapid run off
•Steep slopes
•Deforestation
•Urbanisation
•Draining farm
land
•Dredging
•Afforestation
•Dams + reservoirs
•Straighten channels
•Strengthen levees
•Diversion channels

15. With the aid of diagram (s)
Explain the formation of waterfalls (6)
• Alternating bands of hard and soft rock
• Rapids
• River erodes the softer, less resistant bands of rock
• Hard rock undercut
• Soft rock worn away through processes of hydraulic action
(force of running water, compresses air in cracks in rock and
leads to rock weakening and crumbling) and abrasion (action
of running water and it’s load, wearing away at channel sides)
• Plunge pool is formed at base of waterfall
• Overhang eventually collapses providing more material for
river to further deepen plunge pool
• Process continues repeating, eventually river erodes further
back upstream, leading to the formation of a gorge
downstream

17. Meander bend
A B
A cross section through a meander
CONVEX CONCAVE
Slow SPEED OF FLOW Fast
Shallow DEPTH Deep
Deposition PROCESS Erosion
Slip off slope FEATURE River Cliff

18. 2007 Q2 (b) Explain why the meander cross-
section has this shape
The meander cross section is asymmetrical.
The river cliff is formed on the outer bend of the meander. This is
where the water is deeper and moves more quickly.
Hydraulic action and abrasion wear away at the side of the
channel, undercutting the river bank to form a river cliff.
The slip-off slope is formed on the inside bend by deposition of
alluvium.
Because the water is shallow and moving more slowly at this
point the river load gets deposited to form a gentle slope.

20. River features: Ox – bow lakes
• With the aid of diagrams, explain the
formation of an oxbow lake (6 marks)
(AQAA04)
•Form from a meander
•erosion on outside bend especially by hydraulic
power
•deposition on inside bends where water is
shallower and lower velocity
•neck narrows, breaks through in time of flood
•deposition seals ox bow lake
•eventual loss of lake to form meander scar

21. Formation of a floodplain
The floodplain is the wide, flat area of land either side of the river in
its lower course.
Floodplains contain sediments, often accumulations of sand, gravel,
loam, silt, and/or clay. Features of a floodplain include: meanders, ox-
bow lakes & levees.

22. How does a floodplain form?
The floodplain is formed by both erosion and deposition.
1. Lateral erosion is caused by meanders and the slow
migration downstream to widen the floodplain.
2. The river carries large quantities of suspended load.
3. The deposition on the slip off slopes provides
sediment to build up the valley floor.
4. As the water floods onto the floodplain it loses
energy, there is greater friction, the water is
shallow and the rivers velocity falls so deposition of
its suspended load occurs. Regular flooding results in
the building up of layers of nutrient rich alluvium
which forms a flat and fertile floodplain
5. Over thousands of years the deposits build up to
form great thicknesses of alluvium which is why
floodplains have fertile soil for farming.

23. The Physical Causes of the Floods
• Most of the country is less than 1 metre above sea
level
• Snowmelt from the Himalayas
• Bangladesh experiences heavy monsoon rains,
• Tropical storms (= cyclones) bring heavy rains and
coastal flooding
• The main cause was the above average & long period
of heavy rain which caused all 3 rivers to have their
peak flow at the same time!!!

24. The Human Causes of the Floods
1. Deforestation in Nepal and the Himalayas increases
run off and soil erosion which adds to deposition and
flooding downstream
2. Urbanisation of the flood plain has increased
magnitude & frequency of floods
3. Global warming is blamed for sea level rise, increased
snow melt & increased rainfall in the region
4. Poorly maintained embankments (levees) leak &
collapse

25. floods occurred July to Sept
July 2004 - 40% Dhaka was under
water
60% of country was flooded
600 reported deaths
20 million homeless
100,000 in Dhaka suffered from
diarrhoea as floodlwaters left mud
and sewage
35cm of rain fell in 1 day on 13th
Sept
Death toll rose to 750
Airport, roads and railways
flooded
Bridges destroyed
$7billion damage
Rice crop destroyed along with
food supplies – vegetables
Cash crops – jute and sugar
Textbook
page 115

26. Short Term Responses
• Boats to rescue people
• Emergency supplies for food, water, tents and medicines
• Fodder for livestock
• Repair houses, as well as services such as sewage etc
• Aid from other countries
Long Term Responses
• Reduce deforestation in Nepal & Himalayas
• Build 7 large dams in Bangladesh to store excess water $30-$40
million and 40 yrs to complete
• Build 5000 flood shelters to accommodate all the population
• Build 350km of embankment - 7 metres high at a cost of $6
billion to reduce flooding along the main river channels
• Create flood water storage areas
• Develop an effective Flood Warning Scheme

27. 2006 Q 7c Kielder Case study
• Many urban areas get their water from upland reservoirs.
• Using an example of an upland reservoir that you have studied, explain
the physical and human advantages of its location.
Detailed elaborated or linked statements with precise reference to case study
exemplar. Must cover both physical and human advantages of the location.
Kielder Water is in the relatively narrow valley of the River North Tyne so
the (linked statement) size and cost of building the dam was relatively
small (physical). The local geology is shale, which is impermeable so the
(linked statement) water does not drain away. (physical)
The high rainfall of over 1000mm meant that there (linked statement) was
an ample supply of water.(physical) The area was sparsely populated so
when (linked statement) the valley was flooded there was not too much
disruption to the local population.(human) The water could be used in the
densely populated industrial areas of North East England which are near
by.(human) The population of the north east could also use the reservoir
for leisure pursuits such as fishing(human). (6 marks)

29. Recap – what is the driving mechanism for plate
movement?

30. Two distinct types of crust
Continental Crust Characteristic Oceanic Crust
35-50 km Thickness 5-12 km
Granite (light) Composition Basalt (dark)
to 3.8 billion B.P. Geological age to 150,000,000 B.P.
2.7 Density 3.0
Ave. +1,000 m Elevation Ave. - 3,000 m
No
Remelted and
destroyed
Yes
Yes Deformed No
33% Current distribution 67%
Rate of Plate Movement
San Andreas Fault - 5.5 cm/yr
Mid-Atlantic Ridge: Iceland - 1.8 cm/yr; South Atlantic (Ascension Island) -
3.9 cm/yr
East Pacific Rise - off South America Most rapid movement - 17.1 cm/yr

31. Type of boundary Processes Feature example
Constructive margins
Spreading
Divergent
Two plates move apart
from each other, new
oceanic crust is formed
Mid ocean ridges,
volcanic activity
Mid Atlantic ridge
Destructive margin
Subduction zone
The oceanic crust
moves towards the
continental crust and
sinks beneath it due to
its greater density.
Deep sea trenches and
island arcs are formed
Volcanic activity
Nazca plate sinks under
the South American
plate
Collision zone Two continental crusts
collide as neither can
sink they are folded up
into fold mountains
Fold mountains Indian plate collided
with Eurasian plate to
form Himalayas
Conservative margins
Passive margins
Transform plates
Two plates move
sideways past each
other but land is
neither destroyed nor
created
Fault San Andreas fault
California

32. Supervolcanoes
Yellowstone, USA sits on top of a hot
spot where light molten magma rises
towards and collects in a store beneath
the surface.
When the store of magma is emptied
quickly the land collapses into the
emptied chamber and leaves a caldera

34. How is the distribution of supervolcanoes
different from that of volcanoes?
1. Volcanoes occur in linear belt unlike
supervolcanoes which are more scattered
and occur individually.
2. Volcanoes can occur at destructive,
constructive margins and hot spots unlike
supervolcanoes which can only be found along
destructive boundaries and hot spots.

35. Describe the ways in which a supervolcano is
different from a volcano (Sp paper)
Shape – supervolcanoes are flat and surrounded by
higher mountains unlike volcanoes which are cone
shaped, either gentle or steep. Supervolcanoes form a
caldera whereas volcanoes have a crater
Size – supervolcanoes are much bigger than a volcano
Scale of eruption – supervolcanoes are much more
violent and emit far more material than a volcano.
Impact – a volcano will affect the local area whilst a
supervolcano has a global effect

36. 2011 Describe the likely worldwide effects of a supervolcano
eruption.
Effects likely to refer to impact in immediate area of an eruption – many deaths(87000 predicted), large ash
cloud rising 40 – 50km into atmosphere, destruction of10000 square km of land, ash 15cm think covering
buildings within 10000km, flights suspended, livestock and farmland affected. The UK would see the arrival of
the as h5 days after the eruption; temperatures would fall between 12 and 15 degrees. Parts of Europe and
America and Asia would see constant snow cover for 3 years, cropswould fail, monsoon rains would fail, 40% of
population could face starvation. (6marks)
Level 1 Basic (1-4 marks) Describes effects of a supervolcano eruption.
Statements are general in a random order.
Lots of people will die. There will be huge amounts of ash. People will choke to death.
Buildings will collapse. Crops and animals will die. People will starve. In Yellowstone,
there would be no planes.
Level 2 Clear (5-6 marks)
Effects are clearly described, in an organised way. There is clear reference to
global aspect. Statements are linked.
One in three people will be killed within 1000km of an eruption. Buildings would
collapse within this area due to the weight of the ash. This would ground planes and
make road transport difficult. Livestock would die as they would choke in hot ash.
UK (England) would see the arrival of the ash about 5 days later. This will circle the
Earth, changing the climate. Temperatures will fall by 10 degrees and this will make
it difficult to grow food in many areas. Certain parts of northern Europe will be
snow covered for 3 years, so no food will be able to be grown.

37. SHIELD VOLCANO COMPOSITE
VOLCANO
Constructive
Hot spots
Type of plate
boundary
destructive
basic Type of magma acid
Runny, fluid Sticky, viscous
Gentle, effusive Type of eruption explosive
Gentle sides shape Steep sides
Wide base Area at base Narrow base
Mauna Loa, Hawaii example Mt St Helens,
Montserrat

38. Monitoring and Predicting volcanoes
1. Earthquakes
2. Tiltmeters can identify small changes in slopes
3. Global positioning systems (GPS) use satellites to detect
movement of as little as 1mm.
4. Change in temperature of magma can be monitored.
5. Escaping gases from the vent change before an eruption –
increase in sulphur dioxide.
6. Seismometers used to measure earthquake waves.
7. Analysis of past eruptions; gap between them and pattern
of flows can all help with predictions.
However, volcanoes can still be very unpredictable.

39. Describe the distribution of
volcanoes
1. Not found everywhere –largely found in certain
linear belts
2. Located on plate boundaries – found on destructive
(Pacific Rim) and constructive plate boundaries (Mid
Atlantic Ridge)
3. Destructive plate boundary e.g. Mt St Helens, N.
America
4. Constructive plate boundary – Heimaey, Iceland, Mid
Atlantic Ridge
5. A few volcanoes are located away from plate
boundaries e.g. Mauna Loa in Hawaii – hot spots,
plumes of magma caused by radio active heat within
the mantle

40. Q1a (ii) Explain why volcanoes are found at destructive plate
boundaries (3 marks)
At a destructive boundary an oceanic plate and a continental
plate are moving towards each other due to convection
currents in the mantle
The denser oceanic crust is subducted below the lighter
continental crust.
Pressure is exerted as the plates grind past each other and
friction causes the oceanic plate to melt along with
sediments.
The lighter magma then gets pushed up to the surface via cracks
until it erupts.

41. Volcano case study
Primary impacts Secondary impacts
Immediate responses Long term responses

42. Volcano Mt St Helens pg 19
Primary impacts Secondary impacts
57 died
Trees uprooted
Logging camps
destroyed
River temperatures
raised
Sediment and mud
choked channel
Loss of wildlife
Farming crops ruined
Death of fish in rivers
Flood waters washed
away road and railway
bridges car engines
affected by ash
Electricity supplies
interrupted
Telephone wires cut
Planes grounded

43. Volcano Mt St Helens pg 19
Immediate responses Long term responses
Mobilised helicopters to
search for survivors
Finding shelter for stranded
tourists
Emergency medical
treatment
Providing citizens with face
masks
Clearing ash from roads to
allow traffic to flow
Buildings and bridges
need rebuilding
Drainage needed to be
monitored to ensure no
flooding occurred as a
result of debris
Forest needed
replanting

44. Formation of fold mountains
Destructive boundary (subduction = oceanic crust meets continental
crust)
1. Sediment brought down by rivers collects in a geosyncline, which is a
depression under the sea; this is often near a subduction zone, along a
destructive plate margin.
2. As more sediment collects on top, the sediment is compressed and
turns into rock.
3. Plate movement, caused by convection currents in the mantle, causes
compression of the rocks, which leads to folding, which causes fold
mountains. Eg. Rockies,
Collision boundary (continental crust meets continental crust)
• Himalayas (which are formed along a collision zone).

45. How do people adapt to fold mtns
Farming:
Valley floors – flat, deep fertile soils, sheltered
Transhumance – seasonal movement of cattle up
mountainside allowing hay and fodder to be grown
on valley floor
Milk butter cheese
Plastic tubes carry milk down mountainside
New roads, quad bikes and cable cars give easier access
to upland pastures
Farms are on south facing sides which is warmer
Crops: hay, cereals, sugar been, vines and fruits

46. tourism
• Chamonix – skiing
• Important industry
• Vast amounts of money spent on roads, railways tunnels
avalanche shelters cable cars houses and restaurants
• Tourist facilities benefit locals as well as providing jobs
• Skiers, climbers, walkers, scenery
• Glaciated mountains, snow capped peaks and forests
• Lakes
• Winter sports resorts
• Alps – close to affluent parts of Europe
• Alpine climate has good snowfall, crisp clear days for winter
sports and warm summers

47. HEP
Steep slopes, high perecipitation and summer
melting of glaciers produce fast flowing rivers
that are ideal for generating HEP
Narrow valleys are easy to dam
Lakes in which to store water
Electricity an be used by industries that use
large amounts of electricity – saw mills,
electro chemicals, aluminium smelting

48. forestry
• Trees grow up to 1800m
• Timber industry
• Soft wood felled and used as fuel, for building
and in the manufacture of wood pulp and
paper
• Switzerland – craft industries – wood carving,
cuckoo clocks

49. problems
• High altitude and steep slopes mean it is hard to
build houses, industries and communications
• Roads and railways need expensive tunnels, passes,
shelters and bends
• Little flat land for farming, hard to use machinery
• Cold wet climate – short growing season
• Avalanches and rockfalls block roads
• Need avalanche protection

50. Legacy 2005

51. Any 3 facts from Figure 1
e.g. earthquakes occur in linear clusters (1), many occur on plate
boundaries (1) especially destructive and/or conservative plate
boundaries(1); with example (1). Clustering around edge of Pacific
plate (1).
Maximum 1 for negative

53. Precautions against earthquakes
Individuals Authorities Long term planning
Emergency pack –
water, food, blankets,
first aid kit, radio and
torch
Monitor hazard so
people can be warned
Ensure road and
railways are built to
reduce effects of
earthquakes
Shelter under table or
bed
Have emergency
supplies ready
Ensure new buildings
are earthquake proof
Turn off gas and
electricity
Make plans for shelter,
food and water supplies
and for emergency
services
Provide education and
advertising so people
know what to do.
After earthquake –
move to open ground
Plan to broadcast
information for people
affected

54. 1. Computer controlled movable roof weights to counter the shock
waves
2. Steel frames that can sway during earth movements. Building needs
to be stiff vertically but flexible horizontally
3. ‘Birdcage’ interlocking steel frame, cross bracing to give added
strength and prevent twisting
4. Automatic window shutters to prevent falling glass
5. Sheer core of reinforced concrete and tensioned cables around lift
shaft
6. Fire resistant building materials
7. Outer panels flexibly attached to steel structure
8. Automatic sprinkler system and gas shut off to prevent fires
9. Strengthened steel and reinforced concrete road supports
10. Foundations set deep into the ground
11. Rubber shock absorbers to absorb earth tremors, foundation piles
made out of alternative layers of steel and rubber to make building
flexible
12. Open areas where people can assemble if evacuated

55. Impact of earthquake
• Depends on magnitude of earthquake
and density of the population in an area
• Wealth - People and authorities in
richer areas are generally more
prepared than those in poorer areas
• Wealth means they are able to develop
– Earthquake proof buildings
– More effective emergency services
– Speedier response

57. Tsunamis are caused by earthquakes at sea.
Earthquakes happen when the plates that make up the Earth's surface suddenly
move against each other.
A tsunami forms when energy from an earthquake
vertically jolts the seabed by several metres,
displacing hundreds of cubic kilometres of water.
Large waves begin moving through the ocean, away
from the earthquake's epicentre.
In deep water, the tsunami moves at great speeds.
When it reaches shallow water near coastal areas, the
tsunami slows but increases in height.

58. Cause Effect Response
9.1 Richter Scale
earthquake
caused by the
subduction of the
Indo-Australian plate
beneath the Eurasian
plate.
The sudden movement
of the plate under the
sea caused the giant
wave 5-40 metres
high, which first hit
Sumatra, then Sri
Lanka and Thailand.
Primary effects
•>220,000 people died
•650,000 seriously injured
•2 million homeless
•Many buildings were swept
away by the waves as they
were made of wood
•Roads, bridges and utilities
destroyed
Secondary effects
•Spread of diseases such as
cholera, dysentery
•Loss of coastal fishing
industries
•Loss of tourism revenue from
areas such as Thailand
•Many orphans left due to
children surviving without
parents
Immediate response:
•Panic in the first instance; scale of
disaster meant rescue services and could
not cope.
•Injured people were untreated for days.
•Bodies left to rot in streets.
•Immediate response from international
aid agencies and governments, providing
US$7billion.
•160 aid organisations and UN agencies
helped to provide food, shelter and
medical help
•Provided water purification tablets, food,
sheeting and tents.
Longer term response
•Governments struggled to spend all of
money donated, but progress made.
•Banda Aceh in Sumatra rebuilt, although
still 60,000 Indonesians still living in
tents.
•Indian Ocean Tsunami Warning system
was set up June 2006 to try and give
warning of tsunamis with 39 tsunami buoys
•289 hospitals been rebuilt or
rehabilitated

59. Weathering and erosion work together.
Weathering breaks up and weakens the
surface of rocks but leaves debris in situ
Erosion wears away and removes the
loosened material.

60. Mass movement: movement of material
downhill due to the force of gravity. Can be
very slow eg soil creep, or fast eg mud-slide or
rock fall or rotational slip causing slumping.
Mass movement is increased if there is presence
of water to lubricate; also if there is no
vegetation holding slope in place.

61. Mass movement - slump

62. Why are soft coastlines vulnerable to
rapid erosion?
•Many parts of the UK have coastlines of softer
rocks such as clay which is very susceptible to
erosion and weathering.
•These rocks do not have a strong structure and
become unstable when wet
•A combination of heavy rainfall soaking through
the rock and wave attack at the base of the
cliff may trigger slumping and landslides

63. June 2010
Mass movement is a process affecting the coastal zone.
Describe this process.
(3 marks)
Mass movement occurs when loose material on the land
surface (1) moves downslope (1) due to gravity (1)
sliding and slumping (1).
This is often fast and sudden (1) as with landslides (1)
when the base of the cliff has been eroded, making
the cliff unstable (1).
With a landslide, the whole column of material moves in
one go (1), slumping is similar, but this involves a
curved movement (1).