| Summary: | The aim of this thesis is to use cosmogenic isotope analysis to date a late-glacial stillstand in the eastern Highlands of Scotland. The dates link the extent of the local Cairngorm ice cap and the Scottish Ice Sheet at a particular stage of degiaciation. The constraints provided by such dates add insight to the process of degiaciation and the climatic conditions at the time, The geomorphoiogical and sedimentological evidence suggests that the stillstand lasted around 1 ka and was the last of two or three such stages that affected the region. Cosmogenic 10Be results show that the stillstand occurred at 16-15 ka BP and was synchronous across the massif, Correlations between the Cairngorm 10Be ages, data provided by North Atlantic ocean cores, and the Greenland ice core data suggest that the stillstand in the Cairngorms occurred at the same time as Heinrich 1, the final major iceberg ratting event in the North Atlantic at the end of the last glaciation. independent ,4C and tephrochronoiogicai dating from Loch Etteridge within the Spey Valley show that degiaciation proceeded rapidly after the stillstand. This latter data has been used to provide constraints on erosion rates of granite surfaces in the Cairngorms which are less than 10 mm/ka. Two further implications arise from this work, First the last stage of valley glaciation in the Cairngorms occurred at 16 - 15 ka BP, and thus any Loch Lomond Stadial event (Younger Dryas equivalent) in the Cairngorms was confined to the high corries. Second, the dating of the stillstand shows that the eastern flank of the main Scottish Ice Sheet had retreated to 40% of its LGM extent by the time of the Heinrich 1 Event.
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