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Bedretto Underground Laboratory for Geosciences and Geoenergies

The BedrettoLab (Bedretto Underground Laboratory for Geosciences and Geoenergies) is a unique research infrastructure run by ETH Zurich making it possible to take a close look at the Earth’s interior. It is located in the Swiss Alps 1.5 kilometres below the surface and in the middle of a 5.2 kilometres long tunnel connecting the Ticino with the Furka railway tunnel.

Equipped with the latest technology, the BedrettoLab offers ideal conditions to conduct experimental research focusing on the behaviour of the deep underground when accessing and stimulating it. Such an access is required to advance scientific knowledge in various domains including geothermal energy and earthquake physics. It is also of relevance to develop novel techniques and sensors for these purposes.

Learn more about the scope of the project.

News

2024-05-27

Doctoral thesis exploring geomechanical characterization methods

In his recently published doctoral thesis at the BedrettoLab, Kai Bröker explored geomechanical characterization methods—ranging from mini-frac tests to borehole breakout analysis and hydraulic stimulation experiments—to enhance the understanding of stress measurement in fractured crystalline rock masses. Therewith he shed light on various methods of stress measurements in granitic reservoirs and their implications for hydraulic stimulations. His investigations revealed a complex stress field heterogeneity influenced by natural fractures, fault zones, and tunnel excavation.

Furthermore, his analyses of the hydraulic stimulation experiments suggest hydraulic shearing of pre-existing fractures as a probable reactivation mechanism. The pressure and flow rate datasets and their interpretation will help in the future integration and interpretation of monitoring data for seismicity, strain and pressure as well as in the improvement of numerical models for hydraulic stimulations.

For his doctoral thesis, Kai drew on a wealth of experience that he gained in the BedrettoLab, where he already completed his Master's thesis on “In-situ stress and rock mass characterisation via mini-frac tests at the Bedretto Underground Laboratory”. In addition to his excellent scientific work, Kai has been involved in setting up and developing the BedrettoLab from the very beginning. We, the entire BedrettoLab team congratulate him on his completed doctoral thesis and are happy that he is continuing his work in the BedrettoLab as a postdoctoral researcher at the Center for Hydrogeology and Geothermics at the Université de Neuchâtel.

For more insights, access here the doctoral thesis of Kai with the titel “From stress field heterogeneity to hydraulic stimulation mechanisms: Insights from a hectometer-scale fractured rock mass”.

2024-05-16

First long-term injection experiment successfully finished

At the end of April, the BedrettoLab team successfully conducted their first long-term injection experiment. The experiment lasted several days aiming to generate an earthquake of about magnitude 0 and monitor it from close by.
Following a week of preliminary tests and a four-day preparation phase, high-pressure hydraulic stimulation commenced, with around-the-clock real-time monitoring. The target earthquake occurred at 6 o'clock in the morning of 30 April, somewhat earlier than expected, achieving the experiment's goal and prompting the cessation of injection.

In an earthquake of this magnitude, the rock moves along a plane by about 1-2 millimeters over an area of roughly 5-by-5 meters. This rupture lasts only a millisecond and radiates seismic waves, which our sensitive monitoring arrays are designed to capture. The waves are much too weak to be felt at the surface.
The seismology team uses these detailed recordings of such a small event to study the physical processes that occur during an earthquake. A better understanding of such processes may lead to improvements in earthquake risk mitigation and management in the future. It also contributes to better management of induced seismicity related to deep geothermal energy projects. Currently, the team is analyzing and modeling the collected data, and preparing the next long-term injection scheduled for autumn.

2024-05-06

BedrettoLab team at SOLA Staffette 2024

Last Saturday 14 team members participated at the SOLA Staffette, a relay race covering a total of 113 km in and around the city of Zurich. The team finished in 545th place out of 997 teams and was the fastest among many teams from the Earth Science Department of ETH Zurich.

Virtual Tour

Click on play and get a deep insight into the BedrettoLab.

Geo-INQUIRE call #2

The EU Project Geo-INQUIRE (Geosphere INfrastructures for QUestions into Integrated REsearch) fosters excellent, interdisciplinary and curiosity-driven research of the solid Earth, including land-sea-atmosphere interfaces. An objective of project Geo-INQUIRE is to provide transnational access to unique high-level installations and experiments to selected users to perform research. The BedrettoLab and its three testbeds (Geothermal Testbed, Earthquake Physics Testbed and the Deep Life Observatory) are made available to the research community through the 2nd Open Call for projects, open between May 22nd and July 11th. For further information and to apply please visit the Geo-INQUIRE website.

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