The Aubonne karst aquifer (Swiss Jura)

Abstract

A synthesis of the hydrogeological investigations carried out in an important karst region of the Jura Mountains led to the recognition of a major hydrological system: the Aubonne-Toleure-Malagne system. The continuous monitoring of hydraulic parameters at the main outlets established a mean discharge of the system of more than 6 m3/ s. A delimitation of the Aubonne catchment area is proposed in accordance with the water balance and the geology. Tracer tests outline the presence of a complex karst network which is closely related to the structural context. A schematic organisation of this network is proposed and a major divergence towards the nearby Montant system is set in evidence. Geological observations provide also evidences for a precise delineation of the catchment area: six major functional elements for the recharge of the aquifer are distinguished and transversal drainages towards the Aubonne spring system are outlined along major strike-slip faults. Combining hydrological information available on the Aubonne karst aquifer provides the indispensable background data for the management and the protection of this water resource.