On the size, origin and significance of the Bowscale Tarn moraine

The large size of the Loch Lomond Stadial moraine ridge at Bowscale Tarn has not previously been satisfactorily explained. It is suggested that the debris of multiple rock-slope failures may represent a significant component of the moraine. This is based on the presence of a large mass of broken rock projecting from the base of the cirque backwall. The rock mass seems anomalous in that it occupies a location where erosion by the cirque glacier was likely most intense. If this rock mass is the product of a rock-slope failure that occurred after the decay of the Loch Lomond Stadial cirque glacier, it may indicate that earlier rock-slope failures, both before and during the Loch Lomond Stadial, may have supplied much of the debris that forms the moraine.