Periglacial–deltaic landscapes develop in arctic and subarctic regions, where rivers draining basins underlain by permafrost discharge water and sediment into the sea.
Periglacial Landscapes (Part 2) | A-level Geography | AQA, OCR, Edexcel
Permafrost and periglacial processes
Periglacial Landscapes (Part 1) | A-level Geography | AQA, OCR, Edexcel
Frequently Asked Questions
Is Alaska a periglacial environment?
Far northern and southern hemisphere regions are classed as containing periglacial areas, particularly in the countries of Canada, USA (Alaska) and Russia. Permafrost is where the soil, rock and moisture content below the surface remains permanently frozen throughout the entire year.
What are the characteristics of periglacial areas?
Periglacial environments are characterised by the large amount of angular rock which lies strewn across the land surface. The angular shape of the material suggests that rock fracturing is responsible for its creation and regular freeze thaw processes are at work. Extensive areas of angular rock are called felsenmeer.
What percentage of Earth's land surface is covered by periglacial landscapes?
Beginning about 15,000 years ago, continental glaciers retreated and sea level began to rise. Sea level reached its current height about 8,000 years ago and has fluctuated ever since. Today, glaciers cover approximately: 3% of Earth's surface.
Which is an example of a periglacial environment?
"Periglacial" suggests an environment located on the margin of past glaciers. However, freeze and thaw cycles influence landscapes outside areas of past glaciation. Therefore, periglacial environments are anywhere that freezing and thawing modify the landscape in a significant manner.
Where does the term periglaciation come from and why?
Periglaciation (adjective: "periglacial," also referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing of snow in areas of permafrost, the runoff from which refreezes in ice wedges and other structures. "Periglacial" suggests an environment located on the margin of past glaciers.
Where are the periglacial processes in northern Manitoba?
Figure 10ag-3: Frost-shattered granite bedrock ( felsenmeer ), northern Manitoba. This is a close-up of frost-shattered bedrock, consisting of angular blocks of Precambrian granite. Extensive areas of blocks are called felsenmeer. The shattering has occurred in permafrost terrain, near treeline.
Is the permafrost a necessary condition for periglacial processes?
Permafrost is not a necessary condition for creating periglacial landforms. However, many periglacial regions are underlain by permafrost and it influences geomorphic processes acting in this region of the world.