Periglacial landforms

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(No Transcript)
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Periglacial landforms

• You should be able to describe and explain the
  formation of various periglacial landforms
  including
• Tors
• Blockfields
• Pingos
• Ice wedges
• Patterned ground
• Talus
• Solifluction lobes

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• Patterned ground

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• Ice Wedges

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Describe and explain the formation of open and
closed system Pingos
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Periglacial landforms
http//www.arctic.uoguelph.ca/cpe/environments/lan
d/land_frame.htm
Patterned ground Open system pingos Closed system pingos Solifluction sheets and lobes Tors Ice wedge polygons Nivation hollows Talus (scree) Blockfields
Key features (size, shape, appearance)
Processes involved
Explanation of how created
Located Example
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Open system pingos
Large domes up to 50m high and 300m across. Circular in shape with a core of ice and surface of soil.
Freeze Thaw, Capillary action Formation of Ice lenses
Open system pingos occur in valley bottoms where water moves to the base of the valley during the thaw season when the active layer has thawed. When temperature drops ice lenses can form in this location. Water migrates to these lenses by capillary action. On contact with the ice lenses the water freezes, swelling the size of the lense. Over time this will swell the size of the land surface to create round hills called pingos. When the pingo becomes too large cracks appear on the surface. This exposes the ice to the sun and melting occurs. The pingo collapses leaving a lake (ognip) surrounded by a ridge or rampart.
East Greenland
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Locate your case studies of landforms on the map
below
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Name the features on the diagram


Attempt question 5 and 7 on page 139 of
Waugh Research question 8