A review of cosmogenic nuclide surface exposure dating: new challenges for Scottish geomorphology

Cosmogenic nuclide surface exposure dating has generated important new insights into landscape evolution and surface process rates. The method permits numerical ages to be estimated for landforms that are difficult or impossible to otherwise date with a precision of about 5 % to 20 %. The accuracy and age range of cosmogenic nuclide surface exposure dating depends critically on local geomorphological conditions. Highly stable landscape features such as large glacial erratics yield the most reliable ages, although the technique can be applied with less precise results to stream terraces and other features lacking boulders or bedrock exposures. While landforms as young as several thousand years and as old as ten million years have been successfully dated, the age range in Scotland will generally reflect the duration of late Devensian glaciation between about 30 kyr to about 12 kyr. Cosmogenic nuclide applications require substantial mass spectrometry resources that are presently lacking or in development in the United Kingdom. Recent investments at the Scottish Universities Environmental Research Centre in noble gas and accelerator mass spectrometry presage the development of a world‐class facility in cosmogenic nuclide applications. Major scientific challenges for cosmogenic nuclide surface exposure dating include relating the rapid climatic changes observed in Greenland ice cores to the glacial history of Scotland.