Seismic campaign confirms geothermal potential in Geneva, Switzerland
Geological model of Geneva, Switzerland showing subsurface layers and faults (source: (a) GEothermies – Etat de Genève – SIG)
Carlo Cariaga
15 Nov 2022
The 3D seismic survey done in Geneva, Switzerland confirms the potential of the regional for large-scale geothermal energy exploitation.
The Canton of Geneva and the Industrial Services of Geneva (SIG) have published the results of the 3D campaign survey conducted in Autumn 2021 to evaluate the potential for geothermal energy exploitation in the region. The results confirm the possibility of developing geothermal energy at a large scale in the near future while also providing an unprecedented level of understanding of the Geneva subsurface.
The 3D seismic campaign was completed on October 2021. Carried out in just 5 weeks, this campaign made it possible to acquire data on 80% of the canton and part of its border area. 100 TB of data were collected from geophones, capturing images from between 150 to 5000 meters in depth.
Through these images, new models were generated of the subsurface of Geneva. The models included the orientation, depth, and trajectories of faults fracturing the geologic layers. These are good indications of a potential geothermal system with productive flowrates.
One major discovery stemming from the study was that the faults in the region were oriented east-west, in contrary to the NW-SE direction indicated in textbooks and maps. “This is an incredible discovery that allows us to better understand why the exploratory drilling in Satigny worked well while those in Lully or Thônex did not give the expected results in terms of water flow,” said SIG General Manager Christian Bruiner. This information will be critical in setting drilling targets for the planned exploratory drilling campaign in 2024 and 2025.
The 3D seismic study in Geneva is considered to be pioneering for Switzerland. Without a mining or oil tradition, little is known of the country’s subsurface. “An example to follow! The Geneva data is essential because they contribute to improving knowledge of the subsoil and show that if we don’t carry out such operations, we risk missing out on an important potential that is necessary for the ecological transition in Switzerland,” said National Geological Survey Head Nathalie Andenmatten-Berthoud.
In addition, the experience acquired by SIG and the Canton on the execution of such a campaign will be ratified within the framework of the national program Transfer supported by the association Géothermie-Schweiz and the Confederation. This will help facilitate succeeding operations and thus contribute to the rise in competence in this field.
Source: Geothermies.ch
