Glacial Landforms
Glaciers are large fresh water ice formations.
They are formed by the compression of snow in mountainous terrain.
They move towards sea level at a slower rate than melted water.
This means it still erodes the land but creates different types of landforms to fluvio erosion.
They are formed by the compression of snow in mountainous terrain.
They move towards sea level at a slower rate than melted water.
This means it still erodes the land but creates different types of landforms to fluvio erosion.
Types of Glacier
Niche - Small glaciers on upland slopes
Corrie (Cirque) - Ice masses on mountain sides in arm shaoed hollows
Valley - Glaciers flowing down valleys being fed by a corrie or icefield
Piedmont - Glaciers spreading out when leaving their valley
Ice cap - Large plateaus of ice on high flat land
Ice Sheet - Large expanses of ice - larger than an ice cap
Ice shelf - Extension of an ice sheet over seas
Cold based glaciers - found in polar regions the glacier is ice through to the bed rock
Warm based glacier - Found around the arctic circle the glacier has water at the bottom lubricating the ice aiding movement
Corrie (Cirque) - Ice masses on mountain sides in arm shaoed hollows
Valley - Glaciers flowing down valleys being fed by a corrie or icefield
Piedmont - Glaciers spreading out when leaving their valley
Ice cap - Large plateaus of ice on high flat land
Ice Sheet - Large expanses of ice - larger than an ice cap
Ice shelf - Extension of an ice sheet over seas
Cold based glaciers - found in polar regions the glacier is ice through to the bed rock
Warm based glacier - Found around the arctic circle the glacier has water at the bottom lubricating the ice aiding movement
Glacial Erosion Landforms
Rotational Movement - Downhill movement of pivoting ice
Plucking - Erosional process where rock being carried away by the ice from the surface
Abrasion - Moraine in the ice scrubs against the surface of the rock
Freeze-Thaw - Water continuously freezing enlargens cracks in the rock eventually breaking material off. Common at top of corries
Striations - Lines cut into the surface of the rock in the direction of ice movement
Corrie / Cirque - A 'Bowl' on a mountain side with a steep headwall (back) and generally with a tarn in it
Tarn - Lake in the bottom of a corrie
Arete - Knife edged ridge in between two corries
Pyramidal Peak (horn) - Multiple corries backing onto each other causing a tall sharp peak
Truncated Spurs - Preglacial interlocking spurs that have been cut through by a glacier
Trough / U-shaped Valley - A valley with near vertical sides and a wide flat base
Hanging Valley - During glaciation tributary glaciers enter the main glacier but due to there being less ice there is less erosion and so the valley isn't as deep. Post-glaciation this leaves a valley entering the main valley up the valley side - a hanging valley
Fjord - A trough being submerged by rising sea levels
Ribbon Lake - A long thin lake found in the bottom of a trough
Misfit Stream - A river that forms in a trough with its source from glacier meltwater or a tarn
Roche Moutonnees - Masses of resistant rock with a smooth striated side incline on the upvalley side and a steep jagged downvalley side. Formed when ice moves over more resistant rock and can't erode it flat
Rock Drumlins - Like a roche moutonnees but sediment is placed behind it leaving a smooth downvalley side
Basket of Eggs - A group of drumlins
Crag and Tail - Mass of hard rock (crag) with a steep upper valley side and a smooth downvalley side (tail) where sediment has built up
Till - Material deposited by the glacier - its generally unsorted with variations in rock type throughout
Plucking - Erosional process where rock being carried away by the ice from the surface
Abrasion - Moraine in the ice scrubs against the surface of the rock
Freeze-Thaw - Water continuously freezing enlargens cracks in the rock eventually breaking material off. Common at top of corries
Striations - Lines cut into the surface of the rock in the direction of ice movement
Corrie / Cirque - A 'Bowl' on a mountain side with a steep headwall (back) and generally with a tarn in it
Tarn - Lake in the bottom of a corrie
Arete - Knife edged ridge in between two corries
Pyramidal Peak (horn) - Multiple corries backing onto each other causing a tall sharp peak
Truncated Spurs - Preglacial interlocking spurs that have been cut through by a glacier
Trough / U-shaped Valley - A valley with near vertical sides and a wide flat base
Hanging Valley - During glaciation tributary glaciers enter the main glacier but due to there being less ice there is less erosion and so the valley isn't as deep. Post-glaciation this leaves a valley entering the main valley up the valley side - a hanging valley
Fjord - A trough being submerged by rising sea levels
Ribbon Lake - A long thin lake found in the bottom of a trough
Misfit Stream - A river that forms in a trough with its source from glacier meltwater or a tarn
Roche Moutonnees - Masses of resistant rock with a smooth striated side incline on the upvalley side and a steep jagged downvalley side. Formed when ice moves over more resistant rock and can't erode it flat
Rock Drumlins - Like a roche moutonnees but sediment is placed behind it leaving a smooth downvalley side
Basket of Eggs - A group of drumlins
Crag and Tail - Mass of hard rock (crag) with a steep upper valley side and a smooth downvalley side (tail) where sediment has built up
Till - Material deposited by the glacier - its generally unsorted with variations in rock type throughout
Here are some videos that explain glacial landforms and erosion.
Links: http://www.youtube.com/watch?v=sVEStev3dqM&feature=player_embedded
http://www.youtube.com/watch?v=AG3luuhc-5Y&feature=player_embedded
Links: http://www.youtube.com/watch?v=sVEStev3dqM&feature=player_embedded
http://www.youtube.com/watch?v=AG3luuhc-5Y&feature=player_embedded
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