Geography Erosional Landforms

Corrie = Corries, also known as cirques, are often the starting point of a glacier. Snowflakes collect in a hollow. As more snow falls, the snow is compressed and the air is squeezed out to become firm. With the pressure of more layers of snow, the firm will, over thousands of years, become glacier ice. Erosion and weathering by abrasion, plucking and freeze-thaw action will gradually make the hollow bigger.

Corries will decrease because of climate change due to human activity such as burning fossil fuels. These were used as a source of fresh water.

Tarn = Tarns are formed when more erosion occurs at the base of a cirque then the front. When glacial melt occurs, these depressions fill up with water. One example is Crypt Lake. Other lakes are created when the melt water is damned by glacial deposits called moraines. Alderson Lake and Cameron Lake are examples of this.

Tarns may decrease because of the increase in temperature due to the increase of climate change because of human activity. When it melts it is also used as a fresh water source.

Pyramidal peak = When three or more Corries erode backwards and meet they cannot form an arete; it has steep sides but doesn’t have the length to make a ridge. Imagine three Corries at the corners of a triangle, eventually all eroding back and meeting in the middle. A sharp pointed pyramid shape is created. This is called a Pyramidal Peak.

The peak isn’t really used for anything, and the peaks will decrease and cause flooding in local areas due to human activity.

Arête = When a Corrie is formed, its back and side walls tend to be steep and jagged, perhaps almost vertical. When two Corries form next to each other, and their adjacent walls are eroded backwards until they meet, a narrow and pointed rock ridge is formed. This is often likened to a knife edge, with near vertical sides and a sharp top edge. This feature is called an arete.

Drumlin = Drumlins are elongated hills of glacial deposits. They can be 1 km long and 500 metres wide, often occurring in groups. The drumlin would have been deposited when the glacier became overloaded with sediment. However glaciologists still disagree as to exactly how they were formed.

The landscape can be used for farming because of its fertile soils, or can be used for the development of a settlement or town. These landforms will remain the same; they will not increase or decrease due to human activity.

Kame = A Kame may occur as an isolated hill but more generally each Kame is one mound in a low-lying terrain of many hummocks, terraces, ridges and hollows. Kames often occur in association with kettle holes in the Kame. Eskers may also occur between the Kames. Melt water channels may be cut into and between the Kames. These associations indicate that Kames are formed close to ice margins in situations where there are large volumes of both melt water and debris.

The Kames will increase because more glacial landforms will melt due to human activity. The fluvioglacial land form are not currently used for anything.

Esker = The formation of eskers is linked to the drainage pattern under a glacier. As the ice melts, water flows down through the glacier and drains out the front of the ice sheet. Often, large tunnels channel substantial amounts of melt water which deposit much glacial debris. As the ice melts, increasing amounts of debris are channelled through these tunnels and deposited on the floor. Once the glacier has completely melted, the leftover debris forms a raised ridge, an esker.

They aren’t used for anything at the moment; they will increase due to glacial melting because of climate change. Nivation hollow = Nivation is a collective name for the different processes that occur under a snow patch. The primary processes are mass wasting and the freeze and thaw cycle, in which fallen snow gets compacted into firn. The importance of the processes covered by the term nivation with regard to the development of periglacial landscapes is increasingly questioned by scholars, and the use of the term is discouraged. The term glacier is applied only when ice has accumulated enough for the mass to achieve motion.

These processes are not used for anything generally. These processes will decrease because of human activity.

Pingo = Open-system pingos form when groundwater moves from a distant, elevated source under hydraulic pressure. They typically occur on lower valley side slopes and on alluvial fan surfaces. Closed-system pingos, as in the Mackenzie Delta region, typically form in recently drained lake basins or old drainage channels, and are the result of hydrostatic pressures that develop as unfrozen saturated sediment progressively freezes.

The pingo land form is not generally used for anything; this land form will decrease because of human activity.

Solifluction lobe = Solifluction is the slow down slope movement of waterlogged soil. A solifluction lobe is an isolated, tongue-shaped feature, formed by more rapid solifluction on certain sections of a slope showing variations in gradient. Solifluction adds detail to the terrain underfoot. Small-scale, active landforms include lobes and sheets and turf-banked terraces. The latter reflect also the action of wind in stripping and shaping the vegetation mat and frequently occur in association with deflation surface.

This land form is also not currently used for anything and will increase because: more ice melting means more waterlogged soil which means more solifluction lobes.