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Recessional moraine is a ridgelike accumulation of till which marks a temporary retreat or readvance of a glacier. A period of stagnation followed by further retreat can create such a ridge. A period of stagnation followed by further glacial advance beyond the current ridge can also create this feature; however, the readvancement of the glacier may destroy the form. The recessional moraine is similar to the terminal moraine except that the recessional does not mark the furthest advance of the glacier (a temporary terminal moraine).
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). 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.
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