Meltwater channel near Sandside
Meltwater channels
Meltwater Channels
Definition: channel cut by glacial meltwater under, along and in front of an ice margin. Meltwater may flow under hydrostatic pressure within the glacier and the resultant channels will show up-down long profiles. Alternatively, water may flow under gravity. Meltwater channels are recognizable from their anomalous topographic positions and their large size (misfit) relative to the streams that now occupy them
Meltwater channels are not conspicuous in many parts of Caithness. Good examples occur where the plateau drops towards the Pentland Firth and at Warehouse but no integrated system of channels has been mapped on the plain of Caithness. It is certain that many of the existing rivers occupy channels which were deepened by meltwater erosion during the Ice Age. The Wick River, for example, flowers in a broad, drift-filled valley where the bedrock floor reaches at least 20 metres below present sea level. Rock-cut channels do not seem to be widespread on the ridges and hills that rise from the plain of Caithness. Given the strong streamlining of the terrain due to glacial erosion by ice flowing towards the north coast, it is likely that the main effects of meltwater erosion are hidden in the valleys and depressions between the ridges.