A visit the Audon springs

Tanguy, Lucas and Elie visited the springs of Audon, located north of the Tsanfleuron area. Two major springs, 10 m distant from one another are clearly visible on the aerial photographs of the Audon valley and they provide the bulk of the discharge to the Oldebach (Audon river). The springs are located within a tectonic window into the Diablerets nappe, in the same units which make up the bulk of the Tsanfleuron aquifer. There is a distinct possibility that water from the northern rim of the Tsanfleuron area flows under the Oldehore / Sanetschhore via karst conduits and resurges 2 km away at these springs.

The team characterised the temperature (3.1 °C) and conductivity of the spring waters and measured the discharge by salt dilution. The spring waters were 9°C colder than the surrounding surface torrent, indicating that they travelled underground fast, from a much higher elevation. But are they coming from the Tsanfleuron glacier? A tracer test may prove or disprove this hypothesis, while studying the discharge dynamics of the springs may also reveal a glacier melt source in the summer. This study will be part of a bachelor project.

To begin the characterisation of the site, the team carried out a LiDAR survey of the springs, to build a virtual outcrop. This will be used in turn to assess how to best monitor discharge at the springs continuously.