What is Regelation slip?
Regelation slip • The greater P on the up-ice side of an obstacle may lead to melting. • The water then flows around to the low side (where the P is less) and. refreezes. If the base of the ice-sheet is very cold then the likelihood of basal sliding is very low.
What is subglacial deformation?
As glaciers flow over soft sediments, the movement of the ice above results in the sediments below being ground down and dragged along the direction of flow.
What is basal slip in a glacier?
basal slip: when a thin layer of water builds up at the ice-rock interface and the reduction in friction enables the ice to slide forward. enhanced basal creep: ice squeezes up against a large (>1m wide) bedrock obstacle the increase in pressure causes the ice to plastically deform around the feature.
What is regelation example?
Regelation is a process of generation of melt water from ice which is subjected to higher pressure. Higher pressure of ice mass lowers the melting point and causes to melt the ice. The ideal example that demonstrates this phenomenon would be the melting from the glacier ice.
What is meant by regelation?
Definition of regelation : the refreezing of water derived from the melting of ice under pressure when the pressure is relieved.
What is Regelation geography?
How do glaciers slide?
Glaciers move by internal deformation of the ice, and by sliding over the rocks and sediments at the base. Internal deformation occurs when the weight and mass of a glacier causes it to spread out due to gravity. Sliding occurs when the glacier slides on a thin layer of water at the bottom of the glacier.
What are subglacial processes?
Subglacial processes are the thermal and mechanical processes immediately above and below the boundary between the ice and glacier bed that control glacier motion and processes of erosion, transportation, and deposition.
How are crevasses created?
A crevasse is a crack in the surface of a glacier caused by extensive stress within the ice. For example, extensive stress can be caused by stretching if the glacier is speeding up as it flows down the valley. Crevasses can also be caused by the ice flowing over bumps or steps in the bedrock.
What is the difference between basal sliding and internal deformation?
Internal deformation, which dominantly occurs through ice creep. Glacier flow through ice creep results from movement within or between individual ice crystals, with ice behaving as a nonlinear viscous material. Basal sliding, which refers to slip between a glacier and its bed.
What is regelation short answer?
Regelation is defined as the phenomenon in which the ice melts to the water below 0°C on the application of pressure and refreezes back to ice on the removal of pressure.