The geological features of the Canton of Vaud

As part of the energy transition, the canton of Vaud is seeking to better understand its subsurface resources, particularly to develop deep geothermal energy. Since 2013, the Naturéum has been collaborating on this ambitious project led by the Geology Division of the General Directorate of the Environment.

The Naturéum serves as the repository for archives related to oil prospecting and other underground exploration in the canton. These archives consist of rock samples, such as core samples and drill cuttings, as well as a vast number of documents in both paper and digital formats. The digital documents primarily consist of reflection seismic data—the most effective geophysical method for imaging our subsurface to depths of several kilometers. In medicine, this method is comparable to 2D ultrasound or 3D MRI scans.

Based on this data, Robin Marchant is working to develop a 3D model of the main geological layers in our canton, from the Jura to the Alps, to a depth of approximately 5 km. Such a model makes it possible to identify potential targets for deep geothermal energy projects, whether for district heating networks or for vegetable greenhouses. At the same time, his research contributes new academic insights into the geological history of our regions.

For example, analysis of the bedrock roof has revealed significant over-deepening in the Upper Lake region and the lower Rhône Valley caused by glaciers, which eroded the bedrock to depths of more than 1,000 m below the current topography.

Project Leader : Robin Marchant