esker

Definition

A long, narrow, sinuous ridge created by deposits from a stream running beneath a glacier.

Etymology

From Irish eiscir (“esker, glacial ridge”).

Example Sentences

• "Another unusual ice-contact feature is an esker, a long, narrow, steep-sided ridge of glaciofluvial sand and gravel inhabiting a glaciated area. Eskers tend to follow valleys and lowlands, carefully picking a course between obstacles."
• "Another objection to the tunnel-valley interpretation comes from a comparison with eskers.[…]The esker rivers and the tunnel-channel rivers of Wisconsin therefore seem to have been the result of significantly different meltwater regimes."
• "2001, Allan D. Randall, Hydrogeologic Framework of Stratified-drift Aquifers in the Glaciated Northeastern United States, US Geological Survey Paper 1415-B, page B37, The multiple deltas must have formed sequentially, which led Thompson (1982) to conclude that the eskers were built in successive segments."