Lecture: Britain in the Ice Age: Unstable Slopes in a Frozen Landscape
Speaker:
Entry Fee
Members: Free
Visitors: £5.00
Date and Time
19:30 -
Location
Bath Royal Literary and Scientific Institution, 16-18 Queen Square, Bath BA1 2HN
Lecture Description
Although we think of Ice Age Britain as dominated by glaciers, much of Southern Britain actually lay beyond the ice limits. Here conditions were severely cold, with winter snowfall, extensive permafrost (permanently frozen ground) and very different geomorphological processes from those of today. Permafrost results in near surface and more deep seated structures, including ice-wedges, pingos and cambered strata. Such structures can be used to reconstruct former conditions. During the periglacial periods, hillslopes became much less stable than they are today. Seasonal freezing and thawing of the surface layers caused weathering of bedrock and solifluction of the weathered products, the resulting Head deposits being important elements in the present day Quaternary drift. In areas with clay bedrocks, such as for instance the Cotswolds Escarpment, the Weald and the London Basin, shallow landslides were particularly active. These features are still present as relict landslips in many areas, and if not recognised, may still cause engineering problems.