Karst network geometry and groundwater flow in the Aup du Seuil catchment (Chartreuse, France)

Groundwater flow in karstic aquifers is highly dependent on the geometry of the conduit network. Not integrating the geometry explicitly leads to inaccurate predictions of the aquifer's behavior under both high and low flow conditions.

At the same time, discharge time series at the spring contain information about the internal network organization. Hence, we study how hydrological properties can be related to the statistical metrics developed to characterize network geometry and topology.

One possible way to answer this question is to compare the results of flow simulations in an ensemble of karst networks. We propose using pyKasso, a pseudo-genetic karst network simulator, to obtain a large number of karst networks constrained by the same geological and hydrological settings. We then run flow simulations with openKARST, a flow simulator that handles turbulent and laminar flow in complex karst networks.

Here we present the first results of this comparison exercise on a catchment in the Chartreuse Mountains (France). The Aup du Seuil catchment (~10 km²) was chosen due to its 17-year record of discharge measures at the outlet, and the 25 kilometers of conduits explored and mapped by speleologists. In addition, its geology is relatively simple.