There are quench features at Slag Hill, which is suggesting that the volcanic activity was subglacial. Slag Hill was formed throughout the Pleistocene period, but its most recent volcanic activity produced a lava flow on its western lobe that shows no evidence of ice-contact volcanism.
There are quench features at Slag Hill, suggesting that the volcanic activity was beneath a glacier. Slag Hill originated in the Pleistocene era but showed no evidence of ice interaction during its most recent volcanic event.