- Project: Field Campaign Switzerland | COOLER Project.
- Project date: 16 July, 2021 – 20 July, 2021
- Team members: Peter van der Beek, Cody Colleps, Maxime Bernard and Julien Amalberti
Overview  The COOLER team members went out for a field campaign to sample glaciated and previously glaciated valleys in Switzerland. The European Alps offer spectacular glacial valleys with very distinct (U-shaped) forms attesting to the impact of glaciers on the landscape morphology. We let you judge by yourself with the photos!
Here, we aim to better quantify the impact of glaciers on topography using a high-resolution thermochronometer: 4He/3He on apatite (see page on “Science behind the project”). Indeed, some questions remain on when glaciers first appeared in the Alps, at which extent, how efficient they have been in eroding the bedrock, does the erosion propagate from the valley head downwards or inversely?
Answering these questions is important because erosion of topography implies interactions between tectonics and climate (see page “Science behind the project”). Especially, it is suspected that glaciers are more efficient at eroding rocks than rivers, and thus could have participated to the climate cooling observed during the Late Cenozoic, and to the transition toward more intense glaciations from the mid-Pleistocene, by increasing atmospheric carbon uptake and burial.
For that purpose, we collected rock samples from outcrops (see photos) from which we will extract apatite minerals in the laboratory. After crushing the rocks and sieving the resulting powder, we will carefully separate the apatites using different protocols. Then, after selecting very clean crystals (i.e., no fractures and mineral/fluid inclusions, euhedral shape), they will be sent for irradiation and implementation of 3He. Finally, we will proceed to 4He/3He analyses through step heating experiments, here at the Potsdam laboratory, using a mass spectrometer coupled to a laser (see page “Science behind the project” for further details).
The team looks forward to proceeding to all these steps and get the first results. Stay tuned!