The advance of a glacier by comparatively rapid creep close to its bed, occurring where the ice at the base is at its pressure melting point. The major types are enhanced basal creep, where ice, deformed by stresses created by jagged bedrock, bends round obstructions; regelation (pressure melting); and slippage over a layer of water at the bed. Basal sliding, occurring in sporadic movements, accounts for the majority of flow in warm glaciers, especially where the gradient is steep, the ice thin, or where meltwater is present. Glasser and Bennett (2004) PPG 28, 1 believe that patterns of basal sliding strongly influence patterns of glacial erosion. See also Cohen et al. (2000) J. Glaciol. 46, 155, and Cooke et al. (2006) PPG 30, 5.