LITHOSPHERE
GLACIATION
Lesley Monk
Balfron High School
Session 2005/6
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LITHOSPHERE
deposition GLACIATION
These slide-shows are all on the Prepwork folder if
you wish to copy any notes from them; we will not
be stopping in class for you to do this
LANDFORMS OF GLACIAL DEPOSITION
Materials carried by the glaciers are deposited in
two main ways;
Glacial Deposits (unsorted) and
Fluvio-glacial deposits (sorted)
In the booklet, read the section about this
and also the different types of moraine.
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LITHOSPHERE
deposition GLACIATION
 Moraine
is the waste material worn away and
collected by the ice.
It is angular in shape.
Glacial deposits are poorly sorted, ie all different
sizes and rock types are mixed together.
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LITHOSPHERE
deposition GLACIATION
See the moraine on the glacier surface.
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LITHOSPHERE
deposition GLACIATION
TYPES OF MORAINE
Lateral moraine is found on
the sides of the glacier.
Scree, from frost
shattering, is an important
source.
Ground moraine is
found at the base
(bottom) of the ice.
It is also called till
or boulder clay.
Supra-glacial
Englacial moraine is found
inside the ice itself.
Medial moraine is found
down the middle of the
glacial surface and occurs
when the inner lateral
moraines of two glaciers
join.
Terminal moraine is found
in front of the snout of
the glacier if it is
stationary. It represents
the maximum advance of
the ice.
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LITHOSPHERE
deposition GLACIATION
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There is a handout of this for your jotter!
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LITHOSPHERE
Terminal moraine
deposition GLACIATION
Snout of glacier
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LITHOSPHERE
deposition GLACIATION
Read the booklet- factzone 15 page 37 - and
answer these questions;Q1. In the diagram, in which direction was the glacier
flowing?
A. From east towards the west.
Q2. What is the difference between ablation till and
lodgement till?
A. Ablation till was formed as the ice melted; the
moraine was lowered to the valley floor as the ice
thinned and wasted away. Lodgement till was created in
situ, as the ice ground along the valley floor.
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LITHOSPHERE
deposition GLACIATION
Q3.From which two places is terminal moraine delivered
to the snout?
A. From the subglacial moraine below the ice, bulldozed
in front of the ice, and from supraglacial moraine being
transported along the ice surface to the snout.
Q4. If, after retreating back up the valley, a glacier
starts back down for a short time in a cold spell; what
is formed and why is it small?
A.This recessional moraine is like a terminal, but has
less material bulldozed in front; therefore it is smaller.
The next slides illustrate depositional features
described in your booklet. Read them carefully!
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LITHOSPHERE
ERRATICS
deposition GLACIATION
Erratics are large rocks
that are completely
different from the type
of rocks on which they
rest
They were carried
by the ice-sheet,
sometimes for
hundreds of
kilometres
and then
deposited.
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LITHOSPHERE
deposition GLACIATION
Erratics like this are often found on the
valley floor.
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LITHOSPHERE
deposition GLACIATION
ESKER
Glacial streams are found
under the ice.They are
loaded with debris (sand
and gravel) carried by the
meltwater.
As the ice retreats, the
river deposits its load.
The built-up river bed is
called an Esker.
This river has all but dried
up!
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LITHOSPHERE
deposition GLACIATION
An esker is a steep-sided, long, winding ridge, made
up of gravel and sand. Most are tree-covered.
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LITHOSPHERE
DRUMLIN
Drumlins are smooth,
rounded
mounds of ground
moraine.
The steep (stoss)
side faces the
direction the ice
Moved from.
Drumlins often occur
in swarms or groups
on the valley floor.
deposition GLACIATION
Side view
Plan view
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LITHOSPHERE
deposition GLACIATION
Here is a drumlin outside Buchlyvie.
Can you work out the ice direction?
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LITHOSPHERE
deposition GLACIATION
Meltwater
streams
bringing
outwash to be
distributed
across an
outwash plain.
Note the
braiding of
the stream
channels.
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LITHOSPHERE
deposition GLACIATION
A KETTLEHOLE LAKE
Can you name
the two
Scottish
examples we
learned about
in S Grade?
LOCH MORLICH
LAKE OF
MENTEITH
depression formed when ice melts
depression filled with water to form kettle lake
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LITHOSPHERE
deposition GLACIATION
What is a kame terrace?
GLACIER
Once the ice has
melted, the debris has
been lowered to the
valley floor and
created a terrace with
a steep side and
flattish top.
During the end stages of
glaciation, a lake gathers
at each side of the ice,
filling with moraine.
Kame terraces
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LITHOSPHERE
deposition GLACIATION
This slide shows a set of kame terraces.
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LITHOSPHERE
deposition GLACIATION
Identify the features shown on the diagram by matching
the numbers to the names given.
Esker / Terminal Moraine / Outwash Plain / Drumlin /
Till (Ground Moraine/Boulder Clay) / Kettlehole lake /
Outwash Sands and Gravels.
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LITHOSPHERE
deposition GLACIATION
As you go through your revision, for each
feature mentioned, look back through your
textbooks and this presentation. You are
looking for named examples of as many
features as possible.
Remember that you will get marks in the exam
and NAB’s for showing the skill of quoting
places as examples from your notes!
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LITHOSPHERE
deposition GLACIATION
CONGRATULATIONS!
YOU HAVE NOW COMPLETED
YOUR LITHOSPHERE UNIT.
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deposition - Thurso Geog Blog