Barron, H F, Gillespie, M R and Merritt, J W 2011. Geodiversity of the Cairngorms National Park. British Geological Survey Open Report, OR/10/019 A PDF of this report is available from the NORA, the NERC archive
Site no.: Q20
Site name: Gleann Ballach Moraine
Grid reference:
Locality: River cliff section in Gleann Balloch, 7 km WNW of Newtonmore
GCR Status: N/A
GCR No.: N/A
Type: Natural section
Description: Section through one of a suite of WNW–ESE aligned recessional moraines revealing glacitectonic structures indicative of ice push from the south. Convolute bedding, dewatering structures and slumps affect a unit of silt at the top of the section, clearly post-dating normal faults and glacitectonites at lower levels.
Justification: An important exposure for determining the deglacial history of the region, when a powerful outlet glacier sourced to the west separated from ice sourced locally in the Monadhliath Mountains to the north. A proglacial lake existed for a while at the head of Gleann Ballach, ponded by ice that still occupied Glen Banchor. Dewatering occurred when the lake emptied following retreat of the ice westwards.