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The Work of Glaciers: Erosion, Transportation, and Deposition
Glaciers are massive bodies of ice characterized by their downward or outward movement. These natural agents cover about one-tenth of the Earth's land surface, with 85% located in Antarctica and 10% in Greenland and polar regions. If these glaciers were to melt, sea levels would rise by approximately 65 meters. Understanding glaciers' roles in shaping our planet's surface through erosion, transportation, and deposition is crucial.

Glacial Erosion
Glacial Plucking: When glaciers move, the high pressure at their base causes some ice to melt, allowing water to enter rock fractures and cavities. This water freezes and detaches rock fragments, which are then carried by the glacier.

Glacial Abrasion: As glaciers move, they grind against the bedrock with the help of embedded rock particles, creating a process known as abrasion. This process smooths and polishes the bedrock surface.

Erosional features formed by glaciers include:

Glacial Striations: Scratches on bedrock made by rocks carried in the glacier's base, indicating the glacier's movement direction.
Roche Moutonnée: Rock formations smoothed on the upstream side and steep on the downstream side due to glacial erosion.
Crag and Tail: A resistant rock (crag) protects softer rock (tail) from erosion, forming a distinct feature.
U-shaped Valleys: Glacial valleys with a characteristic U-shape, in contrast to V-shaped valleys formed by rivers.
Hanging Valleys: Tributary valleys perched above the main glacial valley, often forming waterfalls.
Cirques: Bowl-shaped depressions on mountainsides formed by glacial erosion.
Fjords: Deep, narrow, and elongated sea or lake drains formed by glacial over-deepening.
Arêtes, Horns, and Cols: Sharp ridges (arêtes), pyramid-shaped peaks (horns), and narrow depressions (cols) formed by glacial erosion.
Glacial Transportation
Glaciers transport materials in three ways:

Subglacial Load: Materials carried at the glacier's base.
Englacial Load: Materials embedded within the glacier.
Supraglacial Load: Materials on the glacier's surface.
These materials are transported as the glacier moves, eventually being deposited when the glacier melts.

Glacial Deposition
The materials transported by glaciers are deposited as they melt, forming various depositional features:

Drift: General term for all glacial deposits.

Till: Unsorted, unstratified deposits directly left by the glacier.
Stratified Till: Till that has been reworked by meltwater, often forming layered deposits.
Erratics: Large boulders transported by glaciers from their place of origin to a different location.
Moraines: Accumulations of dirt and rocks that have been pushed along by a glacier.

Lateral Moraines: Formed at the sides of a glacier.
Medial Moraines: Formed where two glaciers meet.
Terminal Moraines: Formed at the glacier's furthest advance.
Ground Moraines: Formed beneath the glacier.
Drumlins: Smooth, elongated hills formed by glacial deposits, often found in groups.

Eskers: Long, winding ridges of sand and gravel deposited by meltwater streams within the glacier.

Outwash Plains: Formed by meltwater streams flowing from the glacier, depositing stratified sediments.

Kettles: Depressions formed by melting ice blocks left behind in glacial deposits.

Conclusion
Glaciers are powerful agents of geological change, capable of reshaping the landscape through erosion, transportation, and deposition. By understanding the features they create, we gain insights into past climatic conditions and the dynamic processes shaping our planet.