Standard Grade Geography. Introduction to Glaciation. Physical Landscapes - Glaciation. In this topic you will learn about: What glaciers are and how they have shaped the landscape The processes that create glacial features including plucking, abrasion and freeze-thaw weathering
Introduction to Glaciation
In this topic you will learn about:
Leave a page for your cover page. Copy the list above into your jotter.
The ice age was a period of time when the temperature was much colder than it is today and large areas of land and water were covered in ice. The last ice age ended 10,000 years ago.
During the Ice Age, ice spread out from the poles of the Earth. At the same time, heavy snow fell over the mountains of Britain and Europe. The snow didn’t melt and gradually turned into large rivers of ice called glaciers. These glaciers helped to change the landscape.
During the last ice age, ___________________ years ago, many areas of the world were __________ covered in ice, including much of the UK. In upland area, as more _____ falls it slowly becomes _____________ to form ____. Eventually the whole of ____________ _____________ was covered by a massive _____ ________. In areas of lower ground it just formed in valleys as ________. These bodies of ice moved ____________ shaping the landscape.
Northern Britain glaciers downhill
permanently ice 2 million to 10,000
ice sheet snow compressed
During the last ice age, 2 million to 10,000 years ago, many areas of the world were permanently covered in ice, including much of the UK. In upland area, as more snow falls it slowly becomes compressed to form ice Eventually the whole of Northern Britain was covered by a massive ice sheet. In areas of lower ground it just formed in valleys as glaciers. These bodies of ice moved downhill shaping the landscape.
Like a river, a glacier works as a system with inputs, processes and outputs.
When the glacier melts, it is called ablation. Ablation is higher in summer when the glacier melts.
The glacier grows when there is higher accumulation than ablation. Usually happens in winter
Accumulation > Ablation = Glacier advances
Accumulation < Ablation = Glacier retreats
There are four main agents of erosion:
Only moving ice does not effect the British Isles today – yet it has had the greatest effect on the landscape in the past.
Rain, melted ice or snow
1. Water fills a crack in a rock
2. The water freezes and the crack expands
3. Repeated expansion and contraction weakened the rock and jagged bits break off.
Copy the definition of Freeze-thaw
Task: Copy the definition of ‘Plucking’
Task: Copy the definition of ‘Abrasion’
Occurs at the top of the mountain and provides the glacier with the broken rock it uses to erode
Takesplace at the back of the hollow as the glacier ice removes rock
Takes place at the base of the hollow as the glacier scours and scrapes the rock