Dwarfie Hamars, Hoy
Boulder resting on a moraine ridge at Dwarfie Hamars. The weathering pit has developed from loosening of the Ca cement of the quartz sandstone - as on sandstones of similar lithology at Enegars Corrie and Dunnet Head. The boulder has given a cosmogenic exposure age of x 10Be ka
The Dwarfie Hamars (HY245003) is a large rock face on the south side of the col leading into the valley of the South Burn to the south of Ward Hill. The top of the rock face is about 200 m and the base at about 140 m. The cliff faces N30˚W. The location is most notable for the Dwarfie Stane, a rock-cut tomb dating from the 3rd millennium BC (Ritchie, 1985).
A morainic complex lies between the cliff and the lowest part of the col (at about 50 m). The system can be resolved into three arcuate moraines (Sutherland, 1993) which stretch the length of the free face behind them. Erratic boulders scatter the surface of the moraines and the largest of these is the Dwarfie Stane.
Where the moraine fronts the rock face, there is little scree but east and west of the moraines the slopes are composed of vegetated scree and the rock face is much reduced in size. The implication seems to be that the bulk of the scree developed while the glacier that formed the moraines was in existence.
The moraines can be followed to an altitude of about 70 m. As at Enegars, this is a particularly favourable site for glacier formation, with the broad, almost flat-topped hills behind the Dwarfie Hamars provide extensive areas from which snow could have been blown from both the SE and the SW on to the glacier surface.
