The first association you may have with geoscience are the landscapes - from high mountains and steep cliffs of the Alps to the wide open flatlands of NW France. These landscapes, their evolution, the rivers and glaciers that flow through them, the nature of the soils, and the hazards that they contain, such as landslides, are studied by a field of geoscience known as physical geography. Processes that shaped the modern landscapes are typically on the order of hundreds of thousands of years or less.

The realm below these landscapes contains a record of a much longer history, of millions to billions of years. Geological processes such as sedimentation and volcanism make kilometers-thick piles of rock. These piles contain an archive of the geography of the past, but also life and climate, in the form of fossils and the chemical compounds they contain. At the edges of tectonic plates, these rocks become folded and broken, uplifted and eroded. They are buried and change their mineralogy, they may melt in places, fluids move through them, ore deposits form, earthquakes happen, volcanoes erupt. And the study of the rock record and the long-term reconstruction of the history of the Earth’s geography, climate, life, deformation, and mineralization is covered by the field of geology. And even deeper parts of the Earth, beyond tens of kilometers, is the realm of which the only abundant records come from lavas brought up from the deep studied by geochemistry, or where we use waves or magnetic fields to image Earth’s interior and its processes, studied by geophysics.

Each blog will briefly explain a geo-process that is related to that day’s stage. If you want to know more, find us on Twitter. And if you want to know more about a study in geoscience, check out the institutes where the blog writers work, all over Europe. And maybe we will see you in the field!




The idea for blogs of the Geology of the Tour de France was born out of combining two passions: geology and cycling.

Geoscientists tend to love the outdoors, and are a talkative bunch who can’t stop explaining about their rocks, fossils, landscapes, and natural processes, and the field expeditions they undertook. At some point I realized that viewers of live coverages of cycling races like the Tour de France watch hours and hours of geological excursions. Surely, we couldn’t let the opportunity pass to geo-monologue! And these races are covered by commentators that explain just about everything that passes the camera. All we had to do is help the commentators to explain a few things about the landscape and underlying hidden treasures. As it turns out, there are quite a few geoscientists who love cycling and watching the race, and quite a few cyclists with a keen interest in the environment. GeoTdF was born.

This web page is dedicated to the Geology of the Tour de France. But on the Twitter account @geotdf, we can’t help ourselves and tweet about the geology of just about every race where we find something to tell you. So if you want your regular geo-fun fact, follow us, and drop your questions should you have any! We hope you enjoy, and we’ll see you on the road!