Question

What is an esker and how does it form?

Answer 1

Hint: Eskers are defined as channel deposits that were allowed to fall to the ground surface as the glacier retreated. Eskers can be found in Maine, Canada, Ireland, and Sweden, among other places. Esker deposits are very often exploited for sand and gravel for construction purposes due to their ease of access.

Complete answer:
What is an esker:
Eskers are sand and gravel ridges produced by glacial meltwater moving via tunnels within and beneath glaciers, or through meltwater channels on the glacier's surface. Sediment accumulates in the canal or tunnel over time. The sediments are left behind as the glacier retreats, forming a ridge on the terrain. Eskers are significant because they can provide information about the behaviour of ice sheets and glaciers. They can provide information on meltwater. They can also aid in the reconstruction of the glacier's former ice surface and snout direction.

How does it form:
Eskers are thought to occur when glacial meltwater deposits sediment in subglacial tunnels, which, given the importance of subglacial water for ice dynamics, means that eskers can provide valuable information regarding ice sheet and glacier shape and dynamics.

Note: Eskers developed in subglacial tunnels are useful instruments for studying glaciers and ice sheets' nature and evolution. They document the drainage routes of basal meltwater at the ice boundary. The weight of the underlying ice puts a lot of pressure on the subglacial meltwater. As a result, it might flow upwards! This means that eskers frequently go upward and rise up local topography on a local scale.