Membre de la SCNAT

La CH-QUAT se conçoit comme une interface pour les scientifiques issus de domaines de recherche et de pratique variés, qui traitent du Quaternaire et plus particulièrement des aspects homme, environnement et climat.en plus

Image : NASA Earth Observatory, Jesse Allen and Robert Simmonen plus

Support 2022

Sonja Scherer / Departement of Earthsciences / ETH Zürich, Switzerland

Reconstructing the final phase of the Last Glacial Maximum Reuss glacier at Blattiswald and the timing and extent of the prehistoric Steinerberg (Rubenen) landslide in the region of Goldau, Schwyz

The Blattiswald region is well known for the abundance of crystalline erratic blocks that could only have been moved there by a glacier. At the end of the Last Glacial Maximum (LGM), a large rockfall occurred likely from the southern Maderanertal region (UR) onto the Hüfi glacier which was flowing towards the Reuss glacier. Hüfi glacier joined with the Reussglacier east of the present day Amsteg (UR), and the boulders were transported over 35 km to the “Blattiswald” (SZ) where they were finally deposited. A key question of the master thesis is exactly when the erratic boulders were deposited. Determining this would provide key data for understanding the final phase of the LGM just before glaciers melted down catastrophically.

The erratic boulder field in the Blattiswald was in part buried by the later prehistoric Steinerberg (Rubenen) event. Of this mass-transport deposit that originated from massive rock slope failure of Subalpine Molasse neither its exact extent nor its date are known. Determining when this major event happened is one of the goals of this thesis. This data can be combined with the existing knowledge of slope failures in the Goldau region to interpret causes and triggers.

Thanks to the financial support from CH-QUAT, I was able to carry out the field work this summer which consisted of mapping the region, finding suitable boulders and sampling for the following chlorine-36 dating on the Steinerberg landslide and beryllium-10 dating on the erratic boulders in Blattiswald.

Sonja Scherer

S. Scherer
S. SchererImage : C. Edwards und S. Ivy Ochs

Simona Breu/ Geoecology Research Group/ Department of Environmental Sciences/ University of Basel, Schwitzerland

Changes in fossil chironomid and cladoceran assemblages along water depth gradients

Paleoenvironmental reconstructions based on lake sediment records rely on proxies including the remains of aquatic invertebrates to interpret environmental change over long-time scales. The aim of my master’s thesis is to find out to what extent fossil invertebrate composition is directly or indirectly influenced by water depth. A new surface sediment dataset describing how the distribution of fossil aquatic invertebrate remains changes across lake basins and in different lacustrine environments will be developed to aid the interpretation of paleoecological studies concerning the interpretation of lake level changes.

For this purpose, surface sediment samples from the supralittoral to the profundal of Swiss lowland lakes including Lake Constance, Moossee, Burgäschisee, Lützelsee, Lake Thun and Lake Zurich were sampled and will be analysed. The analysis will include the identification of chitinous invertebrate remains from 7 to 12 samples per transect, with a particular focus on chironomid and cladoceran assemblages.

Thanks to the financial support of CH-QUAT, I was able to carry out my fieldwork on such a large scale and sample 10 transects. Thank you, CH-QUAT!

Simona Breu

S. Breu
S. BreuImage : S. Schnyder und S. Breu