Glaciation and Ice
Where do you find ice?
Places of high latitude
Places of high altitude
Ice sheets
A layer of ice covering an extensive tract of land for a long period of time
Found in the north and south poles and they are areas of high latitude
Alpine regions and glaciers
Glacial System
Input: zone of accumulation, picks up snow and debris
Storage: were ice and debris are stored in the middle of the glacier and locked there
Output: zone of ablation where meltwater is released
Glacial erosion
Glaciers have massive capacity to erode landscapes, due to their vast
size, weight and constant movement.
Glacial transport
supreglacial - debris going over the glacier down to the moraine pile at the bottom
englacial - through the glacier in the middle
subglacial- a passage along the bottom of the glacier
A Crevasse
A deep open crack in a glacier
Cirque Glaciers or Corries
They are small hollows of high, north facing slopes
Over time ice collects and glaciers develop and begin to move downslope in a rotational manner
Pyramidal Peaks, Horns and Aretes
When a cluster of cirques from around the slopes of a high peak then pyrimidal peaks and horns are able to form.
Along the edge separating two cirques, razor sharp aretes develop - matterhorn, switzerland
U shaped valleys
As glaciers move down valley they continue to reshape it. Valley glaciers are much bigger than cirque glaciers and carry much greater mass of ice. This enables them to erode through abrasion and plucking at a much faster rate. The resulting landform after glaciation is a deep and wide U-shaped valley, with truncated spurs.
Glacial Deposits
Moraine
Lateral moraine - moraine that is picked up via the side of the mountains
Recessional moraine - moraine that builds up at the bottom of a glacier
Eratics
Erratics are large boulders and rocks that are a different type of rock compared to the dominant geology of the area where they stand. They were deposited by previous glaciers.