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Glaciation The effects of large bodies of ice on the landscape and the distinctive landforms created

by erosion, transportation and deposition

Extent of Ice Age Glaciation During the most recent ice age, glaciers (represented on map in white) covered much of

the Earth's northern hemisphere. Ice ages consist of glacial periods and warmerinterglacial periods. Many scientists believe that Earth remains an interglacial state

How do glaciers begin?

Snow accumulates during the winter Some snow does not melt during the summer

This is usually on the mountain tops (north facingslopes)

Next winter's snowfall accumulates on top of lastyearssnow

Some is compressed into ice This process continues until the weight of the ice

becomes too heavy This ice slowly moves downhill

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More snow and ice replaces what has moved and the glacier begins

Corries, cwms, cirques "Near mountain tops where glaciers

formed." Steep back wall and sides, open front

with a lip Formed by new snow collecting in

hollows Compacted and turned into ice due

to new snow on top Moves downhill under its own weight Eroding, abrasion and plucking as it

moves Formation of a corrie: Steepening the corrie

sides and deepening the

corrie floor Lip form due to a

decrease in erosion Today corries often filled

with water forming alake

Process of erosion As a glacier moves

downhill it erodes (wear away) the lands.

Plucking Ice melts, then freezes around a rock and pulls or plucks the rock from the ground as

the ice moves

Abrasion Plucked rocks in the base at the bottom of

the glacier grind and scrape away the landunderneath them when the glacier moves

Freeze thaw (aka. Frost Shattering) Water seeps into cracks in the rock and

then freezes, when water freezes itexpands by 9%, putting the rock underextreme pressure. This is repeated manytimes, causing the rock to shatter. This is atype of Physical Weathering

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Striations Grooves caused by the rocks in the bottom of the glacier scraping against the rock

below (abrasion) These are telltale signs of the Glaciers route

Artes Knife Edged ridge, usually the result

of two corries on different sides ofthe mountain

Formed as the back wall of sides of acorrie are weathered and eroded

Distance between two corries isnarrowed until la "knife edge ridge isformed."

Glacial troughs or U shaped valleys Flat floored, steep sided, U shaped

valley."

Formed as glaciers follow pre glacialriver valleys, easiest way down themountain

The Valley is straightened and thesides of the valley and its floor areeroded

Other glacier also come down fromthe mountain into the main valleybelow resulting in the erosive power ofthe glacier increasing

Hanging valley The creation of hanging valleys and

their waterfalls by tributary valleyglaciers. (a) During glaciation, tributaryglaciers enter a major glacier atdifferent floor levels. (b) afterglaciation ends, the ice melts and theregion is left with hanging valleys. Astream then forms a waterfall as ithurtles over the side of the hanging

valley

Moraines Rock particles carried by the glacier Ground Moraine Lateral Moraine Medial Moraine Terminal Moraine

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Glacial Deposition As a glacier melts and recedes a number of features are left behind Most of these are made from the moraine which the glacier was carrying

Receding Glacier

The farther a glacier moves from its

source of accumulation into

warmer, lower-elevation regions,

the more likely it is to ablate, or

melt. As the ice ablates, it begins to

deposit the material it has eroded in

the mountains, as well as any rock

debris that has fallen into its

crevasses. Just as streams of liquid

water create landforms when theydeposit their load of material,

streams of frozen water glacier

drop their burden and shape the

landscape as they recede.

Erratics These are Alienboulders, scattered over the valley floor after glaciation.

They are most likely pieces of groundmoraine.

Drumlins These are smooth, elongated mounds

of till

Steep on one side, gentle on the other

They are often found in groups

Kettles These form from detached blocks of ice, left behind when the glacier retreats

When the ice melts it leaves behind a depression(hole), which sometimes fills with water(kettle hole lake)

Eskers Very long, narrow ridges of sand and gravel. These mark the course of a sub-glacial

melt-water steam (a stream under the glacier)

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Outwash Plain These are flat areas of meltwater below the snout of the glacier

They are made from till

Eskers, erratic, drumlins are found on this plain

Human Activity in Glaciated Areas (glaciated highland) Tourism

Farming

Forestry

Energy resources

Water Supply

Glacial deposits are mined

Glacial lakes, sport and hydroelectric

Tourism

This marks the end of the glacial, periglacial sections of the notesNot because Im lazy, but

I dont have much time to finish all the notesso

For Coastal Landscape sections of the notes, please refer to these ppt:

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http://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lith

osphere/Lesson%207%20Coasts.ppt

http://dp-geography.wikispaces.com/file/view/Coastal+Processes+and+Landforms.ppt

An important diagram:

Well done! Geo 12s. Good luck in your final test!

http://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lithosphere/Lesson%207%20Coasts.ppthttp://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lithosphere/Lesson%207%20Coasts.ppthttp://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lithosphere/Lesson%207%20Coasts.ppthttp://dp-geography.wikispaces.com/file/view/Coastal+Processes+and+Landforms.ppthttp://dp-geography.wikispaces.com/file/view/Coastal+Processes+and+Landforms.ppthttp://dp-geography.wikispaces.com/file/view/Coastal+Processes+and+Landforms.ppthttp://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lithosphere/Lesson%207%20Coasts.ppthttp://www.clydebankhigh.org.uk/New%20CHS%20Website/Files/Geog/Higher%20Geography%20course/Lithosphere/Lesson%207%20Coasts.ppt