The relationships between stratigraphic and tectonic setting, recharge
processes and underground drainage of the glacierised karst aquifer
system `Tsanfleuron-Sanetsch' in the Swiss Alps have been studied by
means of various methods, particularly tracer tests (19 injections). The
area belongs to the Helvetic nappes and consists of Jurassic to
Palaeogene sedimentary rocks. Strata are folded and form a regional
anticlinorium. Cretaceous Urgonian limestone constitutes the main karst
aquifer, overlain by a retreating glacier in its upper part. Polished
limestone surfaces are exposed between the glacier front and the end
moraine of 1855/1860 (Little Ice Age); typical alpine karrenfields can
be observed further below. Results show that (1) large parts of the area
are drained by the Glarey spring, which is used as a drinking water
source, while marginal parts belong to the catchments of other springs;
(2) groundwater flow towards the Glarey spring occurs in the main
aquifer, parallel to stratification, while flow towards another spring
crosses the entire stratigraphic sequence, consisting of about 800 m of
marl and limestone, along deep faults that were probably enlarged by
mass movements; (3) the variability of glacial meltwater production
influences the shape of the tracer breakthrough curves and,
consequently, flow and transport in the aquifer.