With the Marthalen borehole, Nagra enhanced its knowledge of the Zürich Nordost siting region. Investigations focused on the properties of the underground rock formations – particularly those of the Opalinus Clay in which the deep geological repository will eventually be constructed.
Existing image confirmed
Data for this region were already available from an earlier deep borehole investigation conducted in the community of Benken in 1998 and 1999. In addition, deep boreholes were also drilled in Trüllikon and Rheinau in Stage 3 of the site selection process.
In the Zürich Nordost siting region, the geological layers dip towards the south-east. The deep boreholes provided data that enabled a thorough interpretation of the geological conditions in the Zürich Nordost siting region. The results from the Marthalen borehole matched and enhanced the existing picture of the subsurface.
Find out more about the Benken exploratory borehole in Technical Report NTB 00-01.
Read report
Further deep boreholes
Rheinau-1 borehole
The Rheinau borehole was the third deep borehole to be drilled in the Zürich Nordost siting region as part of Stage 3 of the site selection process.
Trüllikon-1 borehole
The Trüllikon borehole was the first deep borehole to be drilled in the Zürich Nordost siting region as part of Stage 3 of the site selection process.
Bülach borehole
Bülach was the first deep borehole to be drilled in the Nördlich Lägern siting region as part of Stage 3 of the site selection process for a deep geological repository.
Stadel-3 borehole
Stadel-3 was the second deep borehole to be drilled in the Nördlich Lägern siting region as part of Stage 3 of the site selection process.
Stadel-2 borehole
The Stadel-2 borehole was the third deep borehole to be drilled in the Nördlich Lägern siting region as part of Stage 3 of the site selection process.
Bachs-1 borehole
The Bachs borehole was the fourth deep borehole to be drilled in the Nördlich Lägern siting region as part of Stage 3 of the site selection process.
Bözberg-1 borehole
Bözberg-1 was the first deep borehole to be drilled in the Jura Ost siting region as part of Stage 3 of the site selection process.
Bözberg-2 borehole
Bözberg-2 was the second deep borehole to be drilled in the Jura Ost siting region as part of Stage 3 of the site selection process.
Work report
