Switzerland SedyMONT-IP3 project

Applicants: Prof. Dr. Matthias Hinderer, Dr. Jens Hornung, Prof. Dr. Fritz Schlunegger

Funding: DFG (ESF-Project)

Persons in charge: Daniel Franke

Duration: 2009 – 2012

Summary

Alluvial fans represent deposit areas in the mountains in the immediate vicinity of the delivery areas. They contain information about short-term as well as long-term sediment deliveries and environmental conditions (e.g. climate, vegetation). The use of these alluvial fan deposits as an archive is difficult, however, as the sediment bodies usually have a heterogeneous structure and are only rarely naturally exposed. Therefore, most studies are based on surface observations and there are hardly any studies that characterize the internal structure of an alluvial fan.

Within the SedyMONT IP3 project (Eurocores-Topo Europe project network), a digital 3D model of the aforementioned alluvial fan is to be created at the Illgraben alluvial fan (Swiss Alps; 7.5km²) through sedimentological investigations, dating (C14, OSL) and georadar measurements. This possibility arises because the sediment layers are currently being exposed to a depth of up to 10 m due to the expansion of the A9 motorway.

Goals within the IP3 project are:

• Clarification of delivery area development and sediment transport mechanisms in the past.
• Mapping of supply channels and relocation / development of deposit units.
• Identification of short-term events and their repetition rate and change over time.
• Correlation of events that indicate erosion, sedimentation, resting or relocation phases.
• Quantification of sediment volumes from deposit units.
• Estimation of the amount of sediment that was carried away by the Rhone.
• Investigation of control mechanisms of the alluvial fan development, by comparing sedimentation trends with climatic and environmental changes within the region since the last ice age.