Cold Environments: Fluvioglacial Processes and Landforms
Descrição
A Levels Geography (Physical Geography-AS) Mapa Mental sobre Cold Environments: Fluvioglacial Processes and Landforms, criado por Andrew_Ellinas em 09-05-2014.
Cold Environments: Fluvioglacial Processes and
Landforms
The Importance of Meltwater
Melting snow helps to enlarge the shallow nivation hollows
that eventually become corries when the snow turns to ice
Helps to lubricate the base of the glacier.
Transports moraine beneath the ice, where it
provides tools for glacial erosion
When freezes, can help with plucking.
Erode channels and form distinctive depositional features - both in front
of and beneath the ice.
Fluvioglacial Landforms: Meltwater
Related Features
Meltwater Channels
Takes the form of a steep-sided , often dry, valley carved into
the landscape
Most commonly results from the overspill of a lake that builds up
next to or in front of a glacier
Eskers
Long ridges of sand and gravel. They can be up to 30 meters high and usually take the
form of meandering hills-often stretching for several kilometres-that run roughly parallel to
the valley sides.
Meandering shape suggests they were formed by subglacial river deposition during the
final stages of a glacial period
Kames
Kame Terrace: Most extensive type of kame. Results from the infilling or a marginal glacial
lake. When the ice finally melts, the kame terrace is abandoned as a ridge on the valley
side.
Kame Delta: A smaller feature that forms when a stream deposits
material on entering a marginal lake. Small mound-like hills, and can
be identified by their deltaic sedimentation characteristics.
Crevasse Kame: Some kames arise from the flucial deposition of sediments in surface crevasses. When
ice melts, they are deposited on the valley floor to form small hummocks
Outwash Plain
A gentle sloping area of sands and gravels that forms in front of the glacier.
Results from the 'outwash' of sediment carried by meltwater streams and rivers.
At the end of a glacial period, huge quantities of sediment
will be spread out over the outwash plain by great torrents of
meltwater.