William Smith's geological map

'William Smith was probably the first person to realise that geological strata could be mapped using the fossils they contained. It was an incredibly important thing because geological mapping is now crucial in things like mineral resource exploration and civil engineering.'
Dr Paul Taylor, palaeobiologist

William Smith was the first to produce a geological map of an entire nation. While working as a surveyor and visiting various coal mines in Somerset, UK, he noticed that certain fossils were only found in particular layers of rock, or strata. He used this principle to trace strata across the British Isles, eventually publishing his completed map in 1815.

The map was meticulously hand-coloured, using an innovative colour and shading system to represent each of the 23 rock layers.

Although it failed to make the impact Smith had hoped with scientists at the time, the map provided valuable information about the subsurface for canal builders, miners, landowners and agriculturists. The map is now considered an incredible achievement, and Smith's names for strata are still used by geologists today.

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