Video | The geological model that helped build the Elizabeth Line

The geology of central London is complex, especially around Farringdon. Layers of clay, sand, and gravel – sometimes in unexpected places – are shifted by faults. For a deep tunnelling project under London, this posed serious risks. To help manage these risks, the ‪British Geological Survey developed a state-of-the-art 3D geological model.

This model provided a live, evolving picture of ground conditions as tunnelling progressed. The result was a major reduction in risk, time, and cost – including a 70% decrease in the need for in-tunnel testing. It was also the first time a 3D geological model had been used alongside major tunnelling works in the UK.

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