esker

views updated May 29 2018

esker A long, sinuous, steep-sided, narrow-crested ridge which consists of cross-bedded sands and gravels. It is laid down by glacial meltwater either at the retreating edge of an ice sheet, or in an ice-walled tunnel. Subglacially engorged eskers are deposited in subglacial or englacial ice tunnels; to be preserved these tunnels must have been in stagnant ice.

esker

views updated May 18 2018

es·ker / ˈeskər/ • n. Geol. a long ridge of gravel and other sediment, typically having a winding course, deposited by meltwater from a retreating glacier or ice sheet.

esker

views updated May 08 2018

esker Long, sinuous, steep-sided, narrow-crested ridge which consists of cross-bedded sands and gravels. It is laid down by glacial meltwater either at the retreating edge of an ice sheet, or in a subglacial, or englacial ice tunnel, or in an ice--walled tunnel.