Form in high mountains where snow
accumulates to sufficient depths so
that it is compressed, compacted and
recrystallized.
For this reason glacial ice can be
classified as
________________________rock
As the snow accumulates and
compacts it is affected by the
force of gravity and begins to flow.
As the ice flows through the
valley the ice flow broadens the
valley into a U Shape.
Glacier Time Lapse Video
https://www.youtube.com/watch?v=6dFbuaz130c
https://www.youtube.com/watch?v=1s5-IvHVDqg
Weathering of the valleys are not
caused by the ice itself.
If you use Mohs scale of hardness
ice is softer than most minerals.
What could cause a glacier to erode a
valley and cause these scratches in
bed rock?
Sediments carried by the glaciers
causes the weathering.
Ice then freezes around the
sediments and allows the glacier
to carry them away.
Glaciers carry sediments of all
sizes. Some rocks can be the size
of a house.
Glaciers are the only agent of
erosion that can transport such large
sediments.
As an Alpine Glacier moves down
hill it is constantly melting.
When the forward movement of a
glacier is faster than the melting rate
it is said to be _________________.
When the forward movement of a
glacier is slower than the melting
rate it is said to be______________.
As a glacier retreats it leaves behind
its load of sediment. The sediment
that is left behind is an unsorted
mixture of all sizes of sediment.
This sediment is called___________.
Till is left behind in unsorted piles
called_____________________.
After Alpine Glaciers retreat they
leave behind very distinct land forms
Cirque
Horn
Arete
Hanging Valley
U Shape Valley
formed when a
glacial valley cuts across an existing
valley
creating
features
such as
hanging
waterfalls.
Sediments washed off the glacier by
melt water. These sediments are sorted
(stratified) by horizontal and vertical
sorting.
Outwash sediments leave behind
distinct glacial land forms such as
eskers, kames and outwash plains
Large dome shaped hill formed by a
stream running across the top of a
glacier then flowing downward
through a crack.
Long sinuous ridge formed from
water flowing out from a tunnel
under a glacier
The area in the front of the
glacier. Sediments are washed
off the glacier and deposited as
the glacier recedes.
A depression formed by a block of
ice that was buried by sediments as a
glacier receded.
Streams formed in outwash plains.
A white powdery sediment that is
unique to glaciers. It is formed from
the grinding action of an advancing
glacier.
When rock flour is eroded by
water it forms glacial milk.
Sedimentary strata that has been
formed by the deposition of rock
flour can be used to determine
the rate of ablation of a glacier
Thicker layers represent periods
of intense melting of a glacier.
Moraines are piles of till left
behind after a glacier recedes.
Terminal moraines can cause a
moraine dammed lake to form.
These lakes are often sites where
rock flour is deposited
Long smooth canoe shaped hills
made of till formed by an
advancing glacier that ran over an
existing moraine
Drumlins point in the direction that
the glacier was moving. Drumlins
are found in swarms.
Long Island was formed by the
sediment left behind by a glacier
After the departure of the Ice sheet
there was a series of moraines and
outwash plains that formed Long
Island
Braided Stream
Kettle Lake
Kame
Drumlin
Drumlin Shows Direction of Movement
Erratic
Erratic
Cirque
Ablation Zones
U Shaped Valley
Finger Lakes_U-shaped Valleys
Esker-Stratified
Moraine-Till- Unsorted
Roche Moutonnee- Glaciated Knob
Esker- Sorted
Striations
Hanging Waterfall
• http://www.youtube.com/watch?v=hC3VTgIPoGU
Most of the ice sheets that exist
presently are at a latitude of no
less than 60 degrees north.
The North Pole is not covered by
an ice sheet because it is an ocean.
The ice that covers the Arctic
Ocean is only several feet thick
because salt water freezes at a
colder temperature than fresh
water.
Ice Sheets have two main zones
Snow builds up and compresses the
lower layers into solid ice. True glacial
ice forms at a depth of_____________
The area at the edges of the glacier
where it is melting.
If the accumulation is less
than the ablation the glacier
is_________________
If the accumulation is greater
than the ablation the glacier is
____________________
The entire continent of Antarctica is
covered by a continental glacier.
The largest continental glacier in
North America is in Greenland.
This glacier is responsible for the
icebergs in the North Atlantic Ocean.
The Bay of Baffin on the eastern
shore of Greenland is nick named
glacier bay. Icebergs such as the one
that sunk the Titanic came from this
bay