| Summary: | During the last glacial maximum, the Galloway Hills in southwest Scotland acted as a major centre of ice dispersion within the last British–Irish Ice Sheet (BIIS). Six new or recalibrated 10Be exposure ages for samples obtained from boulders near the former ice divide yielded uncertainty-weighted mean ages of 15.15 ± 0.72 ka (Lm scaling), or 15.33 ± 0.74 ka (Du scaling). These ages indicate that the former ice dome centred over the Galloway Hills had almost (or completely) disappeared by ca. 15 ka, imply prior deglaciation of all of southwest Scotland and refute suggestions that ice cover persisted in this area during the Lateglacial Interstade. They strongly support recent models advocating extensive deglaciation of all areas occupied by the last BIIS (apart from the Scottish Highlands) prior to warming at the onset of the Lateglacial Interstade (ca. 14.7 ka). Three samples obtained from boulders on a large latero-terminal moraine (Tauchers moraine) near the former ice divide yielded a weighted mean age of 11.91 ± 0.77 ka (Lm scaling) or 12.01 ± 0.78 ka (Du scaling), confirming that the moraine is of Loch Lomond (Younger Dryas) Stadial age, and suggesting that the moraine was deposited 200–500 years before the end of the stade.
|
|---|