Glacial Ice Formation (Leaving Cert Geography): Revision Notes

Glacial Ice Formation

• These notes give basic details on Glaciation. You don't need to be able to write a 30-mark question on any landforms associated with these topics – you can pick either coastal or fluvial for this type of question

Glaciation

• Glaciation is the spread of large masses of ice over land and sea
• Glaciers are rivers of ice that move slowly
• They move downslope under the influence of gravity and the pressure of their own weight
• Form where rate of accumulation of snow and ice is greater than rate of melting

How Ice Moves

Basal Sliding

• The weight of ice causes friction between the glacier and where it is in contact with the bedrock beneath
• This friction causes heat, so a layer of meltwater forms
• This meltwater acts as a lubricant, allowing the ice to slip downslope

Plastic Flow

• Particles of ice within the glacier are able to bend and flow over the uneven rock surfaces that it encounters
• Ice crystals within the glacier are able to creep past each other
• This type of movement is much slower than Basal Sliding