Glaciated landscapes Glossary Flashcards
Glacier
Compressed snow. Ranging from 1km to the scale of Antarctica
Glaciated landscape
A landscape that has features to form a glacier. These can be active or a relic landscape
Ablation
Loss of mass- ice
Accumulation
More mass- ice
Zone of accumulation
Greater amounts of accumulation than ablation
Zone of ablation
Greater amounts of ablation than accumulation
Equilibrium line
Separates the 2 zones of accumulation and ablation
Glacial mass balance
Difference between the amount of snow and ice accumulation and the amount of ablation occurring in a glacier over a year
System
Set of interrelated elements comprising of components (stores) and processes (links) that are connected together
Pressure melting point
Refers to the temperature at which ice is at the verge of melting
Basal sliding
Sliding of glacier over bedrock
Regelation (or creep)
The base of the ice meets a rock outcrop on the valley floor the ice may flow around it
Intergranular slip
Weight of ice can result in ice crystals changing shape due to compaction. Ice crystals become flattened and slide over each other
Laminar flow
Ice flow in layers
Rigid zone
Upper zone of thew glacier where the ice is brittle and breaks
Plastic zone
Lower zone of the glacier where the under the pressure the ice deforms
Freeze thaw
Process of weathering caused by water, confined in rock joints, expanding as it freezes
Plucking
Rocks and stones become frozen to the base or sides of glacier and are plucked from the ground
Abrasion
Process of erosion whereby stones and rocks become embedded in the base and sides of the glacier
Opened system
Matter and energy can be transferred
Corrie
Armchair shaped hollow found on upland hills or mountains
Geomorphic processes
Natural mechanisms of weathering, mass movement, erosion, transportation and deposition
Weathering
Breakdown of rocks
Erosion
Wearing away or removal of rock
Physical weathering
Breakdown of rock by physical processes
Chemical weathering
The decay of rocks as a result of chemical weathering
Biological weathering
May consist of physical actions such as growth of plant roots
Oxidation
Minerals in rocks react with oxygen, either in the air or in water.
Frost shattering
Extremely low temperatures water trapped in rock pores freezes and expands
Solution
Mineral dissolves in water