sediments are referred to as terminal moraines. During warm periods, meltwaters associated with glaciers
transport and deposit a wide variety of material (see figure 2-16).
Eskers are narrow, sinuous ridges of coarse-grained (sand- and gravel-sized) particles that mark the former
pathways of meltwater streams flowing trough ice tunnels. Small, conical deposits of unconsolidated sediments
that once rested atop the ice sheet and alluvial fan deposits that were originally built up against its edge are both
referred to as kames. A kame terrace is a sand and gravel terrace formed between a melting glacier and its valley
wall. Kame terraces are similar to lateral moraine except that they, like all other glaciofuvial deposits, are sorted
and stratified. Lateral moraines, on the other hand, are composed of unsorted, unstratified debris. Figures 2-17,
page 2-26, and 2-18, page 2-27, show several types of erosional and depositional landforms.
b. Continental Glacier. Continental glaciers, unlike alpine glaciers, are not confined to mountain valleys;
rather, they occur as broad, relatively flat sheets of ice that cover large areas in arctic and polar regions. For
example, the land masses of both Greenland and Antarctica are almost completely covered by huge continental
glaciers. The major landforms associated with continental glaciers are depositional in nature, although a few
minor erosional ones also exist.
(1) Erosional Features of Continentally Glaciated Regions. Continental glaciers, like alpine glaciers,
are capable of grinding and scraping the underlying bedrock as the ice masses flow across an area. This results in
the formation of rounded rock outcrops containing numerous grooves and striations that trend in the direction of
ice movement. Continental
Figure 2-16. Glaciofluvial deposits associated with alpine glaciers
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