The Quaternary (the last two million years)

Although rock was and continues to be created in various parts of the world, over the last two million years, rock formation has not occurred in the Quaternary of Scotland. It may well be millions of years before sediments that have accumulated in the last two million years will become rock. Rather than rock formation, the main influence during the Quaternary period of time on Scotland, has been the shaping of the existing rocks and landscape by ice.

Scotland hasn't always been on the same postion on the face of the Earth and has not always had the same outline. This map * shows how 'Scotland' may have looked during a Quaternary ice age. Scotland's present outline has been drawn on the map to help you visualise the ice sheets occured in relation to the land and seas.

At times throughout its history, there have large parts of the Earth that have been covered by vast ice sheets. The Quaternary has been one of these periods in time. Ice ages have come and gone repeatedly with the last major ice age in Scotland peaking around 18000 years ago. Ice up to 1km thick flowed across the country, scraping rock, gouging u-shaped valleys and eroding mountains. We can see the results of this erosion in almost every part of the country. We also see features that formed as the eroded material was laid down and deposited by the ice. They include boulder clay that covers many parts of the country, and erratics, which are the often-large blocks of rock that have been transported over a distance before being ‘dropped’ by the ice, leaving them scattered on the surface of the land.

The ice sheet weighed heavily on the land, pushing it down. After the ice had retreated and melted, the removal of its weight meant that the land slowly began to rise back up again at a rate of a few millimetres a year, and is still rising. Around the country, we see evidence of the land having risen up at raised beaches, which are strips of land above the current coastline that were once the wave eroded shorelines.

As for Scotland’s global position, it is currently still heading north and it is predicted that it will continue to do so over the next 200 million years or so.