It has already been pointed out that talus is composed of angular blocks of rocks. It has little soil. But there is great variation in size of the component parts of talus ranging from big boulders to tiny rock fragments.
Talus on steep slopes of the mountains is likely to creep. As boulders fall due to frost wedging and gravity from the cliffs above the talus, heaps of rock are built up whose slope may be about 35 degrees, this being the maximum angle of repose for the boulders. At the base of such slopes, the boulders spread out in a fringe or sheet-like form.
Because of its composition, talus holds very little water. But in areas of heavy snowfall, there can be much of ice.
Due to succession of freezing and thawing of ice in the spaces between the boulders and the lubrication by water, the talus has a tendency to creep down-slopes.
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This process is aided by water trapped in the upper part of the talus moving on the solid ice in the lower layers, it may be pointed out that the most of the rock glaciers are the result of talus-creep.
Solifluction is the relatively slow down-slope movement of soil and regolith that is saturated with water. Solifluction is a common phenomenon at high latitudes or at high altitude where there is a layer of permafrost beneath the surface.
During warm season when temperatures are higher, the top layers (30-80 cm) of the soil thaws. But the permafrost layer beneath the surface does not allow the downward percolation of thawed water, so that the unfrozen part of the soil becomes saturated with water.
Which creeps gradually down-slope under the influence of gravity until the next freeze arrives. The portion of soil that freezes and thaws annually, and that moves when saturated, is called the active layer.
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Solifluction is most common in Tundra region. The general effect of this process is to produce rounded hillcrests and landscape free of sharp angular features (the subdued landscapes). Bretz has described many examples of solifluction in Greenland which exhibit particularly the terraces with their typical characteristics.