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End moraine is a ridgelike accumulation of till built along any part of the margin of a glacier. Terminal moraine is an end moraine built at the terminal margin of a glacier which marks the furthest glacial advance. These ridges may vary from pronounced (mainly rock and boulders) to faint swells (mainly clay, silt,and sand). The ridges are rarely continuous because of breaks for drainage or lack of source material during construction; however, the terminal moraine system can have considerable linear extent perpendicular to the previous ice-flow direction. The material is usually unsorted and unstratified. The shape is usually crescent-like in plan and convex-triangular in cross section. In continental glaciation, several crescents (or lobes) may be connected to each other.
These features may be formed by lodgement, pushing, or dumping of the till into the ridge. The composition of the till can vary from 99% clay to 99% boulders(see definition of ice-laid material).
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