A bowl-shaped, amphitheater-like depression eroded into the head or the side of a glacier valley. Typically, a cirque has a lip at its lower end. The term is French and is derived from the Latin word circus.

An elongated ridge of glacial sediment sculpted by ice moving over the bed of a glacier. Generally, the down-glacier end is oval or rounded and the up-glacier end tapers. The shape is often compared to an inverted, blunt-ended canoe. Although not common in Alaska, drumlins cover parts of the Eastern and Midwestern United States (Irish).

erratics

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A rock of unspecified shape and size, transported a significant distance from its origin by a glacier or iceberg and deposited by melting of the ice. Erratics range from pebble-size to larger than a house and usually are of a different composition that the bedrock or sediment on which they are deposited.

A meandering, water-deposited, generally steep-sided sediment ridge that forms within a subglacial or englacial stream channel. Its floor can be bedrock, sediment, or ice. Subsequent melting of the glacier exposes the deposit. Generally composed of stratified sand and gravel, eskers can range from feet to miles in length and may exceed 100 feet in height.

An intermediate stage in the transformation of snow to glacier ice. Snow becomes firn when it has been compressed so that no pore space remains between flakes or crystals, a process that takes less than a year.

A large, perennial accumulation of ice, snow, rock, sediment and liquid water originating on land and moving down slope under the influence of its own weight and gravity; a dynamic river of ice. Glaciers are classified by their size, location, and thermal regime.

A pointed, mountain peak, typically pyramidal in shape, bounded by the walls of three or more cirques. Headward erosion has cut prominent faces and ridges into the peak. When a peak has four symmetrical faces, it is called a Matterhorn.

A sand and gravel deposit formed by running water on stagnant or moving-glacier ice. Crevasse fills or crevasse ridges form within crevasses. Kames form on flat or inclined ice, in holes, or in cracks. A kame terrace forms between the glacier and the adjacent land surface. Shapes include hills, mounds, knobs, hummocks, or ridges.

A depression that forms in an outwash plain or other glacial deposit by the melting of an in-situ block of glacier ice that was separated from the retreating glacier-margin and subsequently buried by glacier sedimentation. As the buried ice melts, the depression enlarges.

A general term for unstratified and unsorted deposits of sediment that form through the direct action of, or contact with, glacier ice. Many different varieties are recognized on the basis of their position with respect to a glacier.

A mountain peak or ridge that pokes through the surface of an Ice Field or a Glacier. It may separate adjacent Valley Glaciers (Greenlandic).

 A Sediment deposited by streams flowing away from a melting glacier.

A broad, low-slope angle alluvial plain composed of glacially eroded, sorted sediment (termed outwash), that has been transported by meltwater. The alluvial plain begins at the foot of a glacier and may extend for miles. Typically, the sediment becomes finer grained with increasing distance from the glacier terminus.

Fine-grained, silt-size sediment formed by the mechanical erosion of bedrock at the base and sides of a glacier by moving ice. When it enters a stream, it turns the stream's color brown, gray, iridescent blue-green, or milky white. Also called Glacier Flour or Glacier Milk.

An unsorted and unstratified accumulation of glacial sediment, deposited directly by glacier ice. Till is a heterogeneous mixture of different sized material deposited by moving ice (lodgement till) or by the melting in-place of stagnant ice (ablation till). After deposition, some tills are reworked by water.

valley glacier[image]