Geology of Great Britain - Overview

Overview

Seismographical research shows that the crust of the Earth below Great Britain is from 27 to 35 km (17 to 22 miles) thick. The oldest rocks are found at the surface in north west Scotland and are more than half as old as the planet. These rocks are thought to underlie much of Great Britain and Ireland (although boreholes have only penetrated the first few kilometres), but next appear extensively at the surface in Brittany and the Channel Islands. The youngest rocks are found in south east England.