| Popis: |
The north-west Highlands (Figure 6.1) contain some of the most spectacular scenery in the country, glaciation having resulted in valley overdeepening, watershed breaching and corrie formation in a landscape that already had considerable pre-glacial relief. There is relatively little known about pre-Late Devensian events in this region. The cave systems of Sutherland have recently been found to contain fossil material and other sediments that predate the Late Devensian, and published uranium-series disequilibrium dates on speleothems imply ice-free conditions around 122 ka (the Ipswichian) and again between approximately 38,000 BP and 26,000 BP (Law-son, 1981a; Atkinson et al., 1986). The latter period of ice-free conditions is also substantiated by radiocarbon dates on reindeer antlers from Creag nan Uamh (Lawson, 1984) of approximately 25,000 BP. Thus there appears to have been an interstadial period towards the end of the Middle Devensian. |
