Boulder, Colorado, USA - Although most people do not regularly appreciate it, geologic maps have been and remain a critical foundation of industrial society. They are used for myriad purposes, from locating and developing natural resources, to identifying and preparing for natural hazards, to building and maintaining infrastructure.

Many people who are familiar with introductory geology, via courses or reading, know that William Smith presented the first good geological map in 1815, a large map covering much of Great Britain. But beyond being the first such map, why was it so revolutionary and why is it still revered?

In the July issue of GSA Today, Peter Wigley addresses these very questions. Through digitization of "The 1815 Map" and poring through contemporary documents, Wigley describes how original map features were produced and presented, and compares these to those used in the generation of modern geologic maps for the same region.

Digital reconstructions of maps of the English county of Somerset used by William Smith in his geologic mapping. (A) Smith's first geological map around the city of Bath on a base map made by Taylor and Meyler (1799). (B) Part of the Day and Masters (1782) map of Somerset known to have been used by Smith. (C) Smith's geological map of Somerset based on his engraved geological lines on a map by John Cary. All maps have been re-projected and overlain on part of Smith's 1815 geological map of England and Wales. Credit: GSA Today; courtesy Peter Wigley and the Geological Society, London.

Two hundred years later, the original map remains astonishingly accurate. The reasons lie in the combination of a brilliantly creative individual, a crucial collaborator, some timely technology, and an intriguing taxation law. While Wigley does not draw parallels to developments over the last few decades, one could certainly suggest a recurring theme and perhaps a future Hollywood movie.