Why can crevasses in glaciers only be 50?
Why can crevasses in glaciers only be 50?
A. Plastic flow occurs below that depth. Glaciers cannot be thicker that 50 Meters. …
Why can crevasses in glaciers be 50 meters deep quizlet?
Crevasses form on the upper portion of the glacier because when a glacier moves over irregular terrain, the zone of fracture is subjected to tension, which forms the crevasse. The reason why it may not form below the depth of 50 feet is because plastic flow seals them off.
How deep do crevasses in glaciers extend down to?
Crevasses may stretch across a glacier, run along its length, or even crisscross it. Some crevasses have measured as large as 20 meters (66 feet) wide and 45 meters (148 feet) deep.
Why are the uppermost 50 meters of a glacier appropriately referred to as the zone of fracture?
Zone of fracture. – The upper most 50 meters of a glacier is appropriately referred to as the zone of fracture. Because there is not enough overlying ice to cause plastic flow, this upper part of glacier consists of brittle ice.
What are 2 types of glacial drift are?
Two types of drift are Till (unsorted, unstratified debris deposited directly from ice) and Stratified Drift (sorted and stratified debris deposited from glacial meltwater).
How can you tell the difference between an end moraine and an Esker?
End Moraine: A type of moraine formed at the outer edge of a glacier or glacial lobe where it paused or stopped. Esker: A sinuous rounded ridge of sand and gravel deposited by the streams that flowed through tunnels at the base of the glacier.
What are visible effects of glacial erosion?
Visible effects of glacial erosion include glacial striations, glacially polished rocks, the presence of glacial erratics, and the sediment deposited at a glacier’s terminus.
How can we prevent erosion under concrete slab?
Fixing Erosion Under Concrete The best way to fix erosion under concrete is to fill voids with material that’s resistant to erosion. This is usually done with the slab jacking process. Scritchlow Concrete Lifting and Slab Jacking uses only crushed limestone and Portland cement which is not susceptible to erosion.