Rotondo Granite

Radiometric dating showed an age of 294 Ma.

[3] The Rotondo Granite forms at least part of Monte Prosa.

[4] The Bedretto Underground Laboratory for Geoenergies which is located in the Bedretto Tunnel (in German "Bedretto-Fenster"), is performing research on deep geothermal energy in the Rotondo Granite.

The underground laboratory is operated by the Swiss Federal Institute of Technology in Zürich (ETH Zurich).

The site was selected, among other reasons, because of the similarities that this rock shows with basement rocks that are expected to be encountered at a depth of 4–5 km below the Swiss Plateau.

Ridge made of Rotondo Granite.
Fresh Rotondo Granite surface in the Bedretto Tunnel.