Glossary



Cirque – a deep steep-walled recess or hollow, situated on the side of a mountain and produced by the erosive activity of a mountain glacier.
Crib – an underwater structure serving as a pier.
Diamicton – non-sorted till.
Drumlin – a low, smoothly rounded hill of compact glacial till, built under the margin of the ice and shaped by its flow.
Epeirogeny – movements of uplift and subsidence that have produced broader features of the continents and oceans.
Erratic – a boulder moved from a distant source region by glaciers and deposited upon glacial retreat.
Eustatic – Of or pertaining to worldwide changes in sea level.
Firn – A material transitional between snow and glacial ice.
Flute – Smooth gutter-like channels or furrows on the face of a rock mass.
Glacial Drift – Rock material transported by glaciers.
Groin – a low narrow jetty constructed of timber, stone, concrete or steel, usually extending roughly perpendicular to the shoreline.
Headwall – A steep slope at the head of a valley.
Jokulhlaups – a catastrophic glacial meltwater flood.
Kame – a mound, knob or ridge composed of stratified sand and gravel deposited by a subglacial stream as a fan or delta at the margin of a glacier, by a superglacial stream, or as a ponded deposit on the surface or margin of stagnant ice.
Kettle – a depression in glacial drift, formed by the melting of a detached block of stagnant ice that was buried in the drift.
Knob & Kettle Topography – an undulating landscape in which a disordered assemblage of knolls, mounds, or ridges of glacial drift is interspersed with irregular depressions.
Loess – a blanket of windblown silt.
Moraine – a mound or ridge of unstratified glacial drift, chiefly till, deposited by direct action of glacier ice.
Moulin – a cylindrical, vertical hole in glacial ice.
Nivation – Frost action and mass wasting beneath a snow bank.
Portage – a carrying of boats and supplies overland between navigable lakes and rivers.
Revetment – a facing of stone or cement to protect an embankment.
Rhythmite – an individual unit of a rhythmic succession or of beds developed by rhythmic sedimentation.
Sandur – extensive proglacial fluvial deposits.
Varve – a sedimentary lamina deposited in sequence in a body of still water. Normally seasonal.

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