A Lateglacial Plateau Icefield in the Monadhliath Mountains, Scotland: reconstruction, dynamics and palaeoclimatic implications
Abstract
The complex record of glaciogenic landforms and sediments in Britain relating to the last
British-Irish Ice Sheet provides the opportunity to reconstruct former ice extents, ice dynamics,
retreat patterns and examine their links to climate change. Yet in Scotland, as in the rest of
Britain, a previously fragmentary approach to palaeoglaciological research has limited our
understanding of glacier dynamics and their relationship to climate, particularly during the Last
Glacial-Interglacial Transition.
The Monadhliath Mountains in the Central Scottish Highlands are dominated by an extensive
plateau area that has received little research attention in the past. The few examples of research
include work by British Geological Survey officers in the early 1900s and J.R. Young in the
1970s. These studies focussed primarily on the geomorphology and sedimentology of isolated
valleys and therefore this PhD research provides the first systematic mapping of the region as a
whole.
Results of remote and field mapping demonstrate that two coalescent plateau icefields, together
covering an area of c. 280 km2, occurred over the southwest and central sector of the
Monadhliath Mountains during the Younger Dryas. Equilibrium line altitudes calculated for the
icefield are of comparable magnitude to those reconstructed for nearby Younger Dryas ice
masses, such as in Drumochter and Creag Meagaidh, but indicate slightly lower precipitation in
the Monadhliath Mountains. ELAs of individual outlet glaciers rise steeply from west to east
across the plateau, indicating a strong local precipitation gradient.
Significant variations in the geomorphology on the plateau and within outlet valleys allowed an
examination of former thermal regime and differences in ice dynamics during retreat. In-depth
analysis of moraine retreat patterns enabled a detailed insight into palaeoglaciological controls
on deglaciation for the first time, concluding that valley morphology and gradient were the most
influential factors on the retreat dynamics of the plateau icefield.
Authors
Boston, Clare MaryCollections
- Theses [3822]