Glaciation Pack O

Question 1

What are the processes and landform changes that happen very quickly (seconds/minutes)?

Answer 1

Mass movement processes e.g. rockfalls, avalanches, lahars, GLOFs

Question 2

What are the processes and landform changes that happen on a seasonal basis?

Answer 2

• Changes in accumulation and ablation
• Changes in flows in meltwater streams and deposition of sediments
• Changes in mass balance of a glacier
• Changes in permafrost (depth of active layer)

Question 3

What time frame are glaciers measured over?

Answer 3

Decades to centuries

Question 4

What timeframes are the Pleistocene, glacials, interglacials, stadials and interstadials?

Answer 4

Millions of years (stadials = millennia)

Question 5

When was the last glacial advance in the UK?

Answer 5

11,500 years ago

Question 6

What is causing change to landscapes over decades or centuries?

Answer 6

• Longer term mass balance of a glacier
• Impacts of climate change on glacier volume/size

Question 7

How and why do previously glaciated valleys and their features change after they have been created?

Answer 7

• Infilling of ribbon lakes
• Misfit streams
• Vegetation growing on scree
• Hanging valleys getting larger
• Scree slopes developing which makes valley more V shaped
• Human modifications
• Peat bogs developing
• Moraines being reworked

Question 8

How do cirques change postglacially?

Answer 8

• Freeze-thaw weathering on slops leads to scree slopes
• Scree slopes may become vegetated
• Tarns may form (e.g. Easedale Tarn)
• Tarn may infill with deposits from erosion of the corrie and disappear
• Tarn may evaporate
• Morainic rock lip may get vegetated or re-worked (natural or human)
• Areas may become saturated with water and form peat from dead organic matter which doesn’t fully decompose

Question 9

How might water stores or rivers change postglacially?

Answer 9

• Water may evaporate from kettle lakes
• Kettle lakes may infill with sediment (e.g. Lake Ronkonkoma)
• Peat bogs may form in poorly drained areas
• Misfit streams may form or dry up
• Ribbon lakes and misfit streams may infill with sediment (e.g. Interlaken)
• Proglacial lakes may drain to form overflow/outwash channels
• May alter drainage basins
• Hanging valley may deepen

Question 10

How may deposits change postglacially?

Answer 10

• Freeze-thaw weathering may form scree slopes
• Scree slopes may be vegetated
• Scree causes U-shaped valleys to be more V-shaped (e.g. Wastwater)
• Deposits may infill lakes or streams

Question 11

How may humans affect these areas?

Answer 11

• Mining
• Tourism
• HEP
• Walking on deposits