Suites of landforms within glacial landscapes Flashcards
What areas are source regions of glaciers and ice caps and have significant ice erosion?
Highland areas.
Which areas often have slower-moving or stagnant ice and significant fluvioglacial deposition?
Lowland areas.
Why would different sides of a glacial trough have different aspects?
Each side has different resistance rock.
What 6 factors have to be taken into account when describing highland landscapes?
- Landscape at source (cirque)
- Features of glacial trough (hanging valley)
- Depositional features (moraines)
- Micro-features (striations, chatter lines
- Periglacial features above trim line (ice-marginal moraine)
- Post-glacial modifications (fluvial erosion)
What are the key variables in ice sheet erosion?
Ice thickness
Speed
Temperature regime
Underlying relief
Geology
Age of ice sheet
what are 3 typical examples of lowland glacial erosion landforms?
Lochans, Roches Moutonees and Crag & Tail
What is a chaotic drainage pattern?
Where residual moraines block traditional drainage patterns
What is there little of in cold-based ice sheets?
Erosion - they are usually stationary
When will ice sheet deposition occur?
When multiple ice sources coalesce into huge ice sheets and significantly slow down, losing energy and therefore depositing large clast.
What is the most common ice sheet deposition feature?
Moraines - it is easy to tell when there have been series of readvances, stillstands and recessions.
What is an example of a variation in glacial environments that occurs over seconds?
Mass movement such as rock falls, GLOFs and overflows.
What is an example of a variation in glacial environments that occurs seasonally or annually?
Changes in Acc and Ab
Flows of Meltwater Streams
Changes in Permafrost
Changes in Net Balance of Glacier
What is an example of a variation in glacial environments that occurs decadal or centennial?
Trends and balances of glaciers
Impacts of global warming on size
What is an example of a variation in glacial environments that occurs over a millenium?
Formation of sea-level change features
Stadials & Glacials
Post-glacial modification by fluvial actions
What is an example of a variation in glacial environments that occurs over millions of years?
Pleistocene Ice Age
