The meltwater channel systems on the northern flanks of the Lammermuirs
Meltwater channel systems
The meltwater channel systems of part of East Lothian
Meltwater channels rarely form singly. Instead, the channels form meandering and branching networks, often with gaps or breaks where meltwater has flowed within the glacier rather than across its floor.
East Lothian shows a magnificent system of meltwater channelson the flanks of the Lammermuir Hills. The system has a SW-NE trend reflecting the ice surface slope and direction of flow of the last ice sheet but with diversion around prominent hills. The system represents the many conduits for meltwater flowing beneath the ice.
Individual channels are of different age and origin. Several channels, such as at Longyester, are partly plugged by glacial till or sand and gravel and so predate the latest ice movements. Other have up-gradient segments that relate to water moving uphill under pressure, whereas others are clearly gravity flow channels. Locally, one channel set cut across and older set. These relationships indicate that the Lammermuir system has been re-occupied by meltwater during many phases of glaciation.