Testament to a major phenomenon : continental break-up
The Chaîne des Puys-Limagne Fault Tectonic Arena constitutes a unique geological theatre staging one of the large-scale phenomena that has fashioned the surface of our planet: continental break-up (or ‘rifting’).
The landscape of this tectonic arena shows how the Earth’s crust fractured, then subsided, followed by the rise of magma to the surface, accompanied by widespread uplift.
350 million years of geological history
The different geological forms found in the Chaîne des Puys-Limagne Fault Tectonic Arena reveal the successive stages of the rifting process: an ancient continental plateau (the Plateau des Dômes), was stretched, fractured and subject to subsidence (along the Limagne Fault). The surface was then significantly uplifted, leading to major erosion and the formation of inverted relief (the Montagne de la Serre). At the same time magma rose to the surface following fissures created by the extension and fracturing, giving rise to volcanoes (the Chaîne des Puys).
Discover more about the site under the following six headings :
The Plateau des Dômes
This ancient continental basement, relic of a former mountain chain which had been completely planed off by erosion, was fractured during the rifting process.
The Limagne Fault
This 700 m-high fault marks the boundary between the Plateau des Dômes (ancient continental basement) and the subsidence basin (the Limagne Plain) which formed during continental break-up.
The Montagne de la Serre
This ancient lava flow, which originally lay in a valley bottom, is now a raised plateau due to the effects of 3 million years of erosion.
The Chaîne des Puys
This volcanic alignment of 80 varied edifices (domes, cones, maars and lava flows) was formed by rising magma which followed fissures created by the rifting.
A living site
A natural and inhabited site
Man has fashioned the Chaîne des Puys over the last 6,000 years. By maintaining a balance between the forest and the grasslands, the clarity of the volcanic forms is preserved.
A scientific arena
The site is currently the object of a number of scientific research projects, such as imaging the interior of volcanos, drawing analogies with structures on Mars to better understand them, etc.