Physical Environments: Lithosphere: Glacial Deposition
PHYSICAL ENVIRONMENTS: LITHOSPHERE
GLACIAL DEPOSITION
Kettle holes
Kettle holes result from large pieces of ice taking a
while to melt once the glacier retreats and causes
a depression in the ground. Sometimes it can be
filled by water.
Glacial deposition took place mainly in lowland areas. Depositional features were formed either
under the ice or beyond the terminal moraines onto the outwash plains in the UK.
DON’T FORGET
Learn the names of specific
features – you’ll get credit
for these in the exam!
Glacial transportation can take eroded material a very long way. Evidence for this exists
in the form of erratics – large rocks found considerable distances from their source
areas. A mix of rocks, clays, sands and silts is added to the moving glacier by weathering
and erosion processes. When the glacier melts, all this englacial material is deposited as
one of two types of glacial drift:
1 Unsorted and unstratified material deposited directly by the ice is called till.
2 Sorted and stratified material deposited by the meltwater flowing out of the glacier
forms fluvio-glacial deposits.
Glacial deposition landforms
FEATURES OF GLACIAL
DEPOSITION
Drumlins
Underneath the ice, clay containing angular
rocks covered the lowlands. These deposits
are known as boulder clay/till. The surface of
the boulder clay can sometimes be marked by
long rounded hills called drumlins. Often over
100m high, drumlins are created when material
is deposited due to friction between ice and
underlying rock which causes the glacier to
deposit its load.
Erratics
Sometimes, glaciers
picked up large boulders
which were transported several hundred
miles. This means rock types are different
between the erratic and the area it was
deposited in when the glacier retreated.
Eskers
Eskers are created inside the ice by rivers and streams. These
carry stratified sands and gravels and when the ice retreats the
rivers build up these ridge-like deposits.
Moraines
Terminal moraine
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The terminal moraine marks the maximum extent of a glacier
across a valley. Lateral moraines are found at the sides of a
u-shaped valley, caused by the freeze thaw action of bare rocks
above the glacier. Medial moraines are found in the middle of a
u-shaped valley running parallel with the valley sides. Recessional
moraines are found when the ice retreated, then advanced a
little, deposited some material, retreated further, advanced again,
depositing some more material, parallel to the terminal moraine.
contd
SAMPLE PAGES – CFE HIGHER GEOGRAPHY
PROCESSES OF GLACIAL DEPOSITION
Outwash plain
The outwash plain is the area
beyond the terminal moraine. The deposits here have been carried
away from the glacier by meltwater. They are well-sorted, i.e. the larger
materials are closer to the moraine and the finer materials, like sand,
end up much further away.
Kames
Kames are irregular shaped mounds
of material consisting of sands and
gravels, generally found on the sides of valleys. They were
created by streams running along the side of the ice.
SUMMARY
Till deposits are unsorted and unstratified materials deposited
by the ice, including:
●● drumlins
●● medial moraines
●● terminal moraines
●● recessional moraines
●● lateral moraines
Fluvio glacial deposits are sorted and stratified materials
deposited by meltwater, including:
●● outwash plains
●● kettle holes
●● askers
●● kames
ONLINE
For more on glacial
deposition, follow the link at
www.brightredbooks.net
THINGS TO DO AND THINK ABOUT
(a) Fully describe the evidence which suggests that the area shown in the photograph
has been affected by glacial erosion.
Hint – your answer should mention features you can see in the photograph.
ONLINE TEST
Head to www.
brightredbooks.net and test
yourself on this topic.
DON’T FORGET
(b)Choose one feature of glacial erosion shown in the photograph and, with the aid of
diagrams, explain how it was formed.
Hint: Your answer should mention glacial processes.
Practice the diagrams. The
more you practice, the less
time will be taken up trying
to create “works of art”.
A well-annotated diagram
could get full marks in the
final exam.
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Human environments: Population: Census and migration 1
HUMAN ENVIRONMENTS: POPULATION
•
CENSUS AND MIGRATION 1
•
•
COLLECTING AND COLLATING DEMOGRAPHIC DATA
VALUE OF DATA COLLECTION
The variety of demographic sources allows for a general picture of a population’s
social and economic state to be drawn. However, data collection is extremely costly and
challenging for governments to perform. Originally a census was performed to allow for
taxation and army recruitment. Today, census information is mainly used for providing
public services. These include:
• maternity care
• employment, housing and transport
nursery
education
•
• pensions
primary
education
•
• geriatric health care
secondary
education
•
• sheltered housing.
higher
education
•
Censuses
Population data is collected through a process called a national census. Many
countries use this detailed form to gain information about both the social and economic
components of a population and census data collection has a long history in the world.
Most countries in the world collect data on their populations.
The data collected includes information on every member of a household, including their
age, sex, religion, health, job, education, birth place, (in Scotland their knowledge of the
Gaelic language) and their means of travel/transport to work. The census also collects
information on lifestyle, living conditions, house tenure and amenities.
In the United Kingdom a census is performed every 10 years. The collection of census
data is the responsibility of the Office of National Statistics in England and Wales and the
responsibility of the General Registration Office in Scotland. This census data allows a
snapshot of social and economic development to be gained.
Census data is collected through enumeration districts and all census forms are
collected by an enumerator, who ensures that all individuals are recorded. The results
are collated and analysed to interpret population change, forecast population trends,
allow for planning to take place for the future demands which will be placed on services
and to allow for strategic planning for the areas listed above. Further to this, censuses
allow governments to make informed decisions about whether or not to encourage or
discourage births, deaths and migration.
Demographic data collection difficulties
DON’T FORGET
EDMC = Economically
More Developed Country.
ELDC = Economically Less
Developed Country.
Demographic data collection is always improving in terms of quality and quantity.
Generally speaking, census data collection is more reliable in an Economically More
Developed Country (EMDC). However this is not always the case. For example people can
be unwilling to complete a census for fear of increased taxation. This was the case in 1991
in the UK’s census when over one million people’s census information went missing.
Distortion of census data can be related to a combination of several factors. In developing
countries (ELDCs) there are a variety of reasons for obstacles in the face of data
collection. These include:
• expense – debt ridden countries have • nomadic populations are difficult to
other priorities
include
SAMPLE PAGES – CFE HIGHER GEOGRAPHY
There are several ways of collecting population data and each has its own limitations.
These include:
• censuses
• civil registration – births, • national, European and
marriages and deaths
global surveys.
under-registration for social and
religious reasons, for example under
recording females due to the one child
policy in China
low literacy rates
variety of languages – it costs money to
translate a census into many languages
and there are also unofficial languages/
local dialects which are difficult to
translate into
•
•
•
•
•
ethnic tensions can lead to influenced
inaccuracy
urban-rural migration
poor communication links, difficult
terrain and scattered settlements
civil wars lead to mass migration
poor infrastructure.
DON’T FORGET
Migration brings both
advantages and
disadvantages for the
source location and the
new location
MIGRATION
When individuals move from one place to another on either a permanent or semipermanent basis, this is called migration. This can be for:
•
years
•
•
months
seasonal reasons.
Migration types
Migration can fall into several categories: temporary or permanent, voluntary or forced.
The migration is also categorised according to the reason for movement, for example, as a:
Refugee ➞ a refugee is a person who
is stateless, who has found themselves
without homeless or displaced in some
way. There can be one or several reasons
for someone to find him/herself a refugee,
which include; war, religious or ethnic
persecution or famine. Normally refugees
do not have many belongings or any
documentation to prove who they are.
Economic migrant ➞ an economic migrant
is someone who has made the decision to
move in order to earn more money and
to directly improve their quality of life.
Often economic migrants send remittance
payments back to their families in their
home country.
Asylum seeker ➞ an asylum seeker
is someone who is looking for shelter
because they have found themselves in a
threatening situation in their home country
and declares this in their ‘host’ country
when they arrive. Asylum seekers can be
fleeing religious or ethnic persecution
and feel that they are in immediate or real
danger of imprisonment or death if they
were to return to their homeland.
Voluntary ➞ this is when people have
made the conscious decision to freely move.
Permanent ➞ this type is migration is on a
long term basis.
Forced ➞ this is when individuals have no
choice but to move.
International ➞ this involves crossing a
national boundary where identification
checks are performed.
Internal or Intranational ➞ this is when
the migration occurs within a country or
even within a city.
There are basic factors that encourage individuals to migrate from one area to another.
These factors can be categorised into push and pull factors which either encourage
people to leave their original location or attract people to a new location of destination.
Sometimes these basic factors can seem more aspirational than realistic when the move
has been made.
THINGS TO DO AND THINK ABOUT
Look at the link at www.brightredbooks.net and makes notes under the following
headings:
• What is migration?
• People who migrate
• Migration types
• Migration impact
ONLINE
Learn more about Scotland’s
censuses online at www.
brightredbooks.net
ONLINE TEST
Want to revise your
knowledge of this topic?
Test yourself online at
www.brightredbooks.net
contd
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