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Gabrovsek, F., Häuselmann, P., & Audra, P. (2014). 'Looping caves' versus 'water table caves': The role of base-level changes and recharge variations in cave development. Geomorphology, 204, 683–691.
Résumé: The vertical organisation of karst conduit networks has been the focus of speleogenetic studies for more than a century. The four state model of Ford and Ewers (1978), which still is considered as the most general, relates the geometry of caves to the frequency of permeable fissures. The model suggests that the water table caves are common in areas with high fissure frequency, which is often the case in natural settings. However, in Alpine karst systems, water table caves are more the exception than the rule. Alpine speleogenesis is influenced by high uplift, valley incision rates and irregular recharge. To study the potential role of these processes for speleogenesis in the dimensions of length and depth, we apply a simple mathematical model based on coupling of flow, dissolution and transport. We assume a master conduit draining the water to the spring at a base level. Incision of the valley triggers evolution of deeper flow pathways, which are initially in a proto-conduit state. The master conduit evolves into a canyon following the valley incision, while the deep pathways evolve towards maturity and tend to capture the water from the master conduits. Two outcomes are possible: a) deep pathways evolve fast enough to capture all the recharge, leaving the master conduit dry; or b) the canyon reaches the level of deep pathways before these evolve to maturity. We introduce the Loop-to-Canyon Ratio (LCR), which predicts which of the two outcomes is more likely to occur in certain settings. Our model is extended to account for transient flow conditions. In the case of an undulating master conduit, floodwater is stored in troughs after the flood retreat. This water seeps through sub-vertical fractures (soutirages) connecting the master conduit with the deep pathways. Therefore, the loops evolve also during the dry season, and the LCR is considerably increased. Although the model is based on several approximations, it leads to some important conclusions for vertical organisation of karst conduit networks and stresses the importance of base-level changes and transient recharge conditions. It therefore gives an explanation of speleogenesis that relies much more on the dynamic nature of water flow than on the static fracture density
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Malard, A., Jeannin, P. Y., Sinreich, M., Weber, E., Vouillamoz, J., & Eichenberger, U. (2014). Praxisorientierter Ansatz zur Kartographischen Darstellung von Karst-Grundwasserressourcen – Erfahrungen aus dem SWISSKARST-Projekt. Grundwasser – Zeitschrift der Fachsektion Hydrogeologie, 19(4), 237–249.
Résumé: Trotz ihrer großen Bedeutung als Wasserressource steht für Karst-Grundwasserleiter auch in der Schweiz eine systematische Abgrenzung und quantitative Beschreibung noch aus. Das Fehlen eines integralen Ansatzes zur Charakterisierung von Karstsystemen mag dazu beigetragen haben. Im Rahmen eines Projektes zur Dokumentation der Karst-Grundwasserleiter in der Schweiz (SWISSKARST) wurde mit der KARSYS-Methode ein pragmatischer Ansatz zur hydraulischen Charakterisierung einzelner Grundwasserleiter und Karstsysteme entwickelt. Eine Weiterentwicklung dieses Ansatzes beinhaltet ein Verfahren zur kartographischen 2D-Darstellung des erstellten 3D-Modellkonzepts, welche sowohl auf wissenschaftliche als auch auf Fragestellungen der Praxis ausgerichtet ist. Dazu werden zunächst mehrere thematische Karten mit den wichtigsten Eigenschaften der Karst-Grundwassersysteme erstellt, welche dann zu einer synthetisierten Karte zusammengefasst werden. In spite of their significant water resource, in Switzerland as well as in other countries, the location and extent of karst aquifers have not been systematically studied and documented yet – mainly due to the lack of systematic and dedicated approaches for their characterization. In the framework of a project aiming at documenting the karst aquifers in Switzerland (SWISSKARST Project) the pragmatic KARSYS approach has been elaborated to systematically assess the main characteristics of karst aquifers and karst systems. One part of this project deals with the development of a 2D karst hydrogeological map representation, which is designed to address both scientific and applied issues. A series of maps based on the approach is proposed to describe the main characteristics of karst groundwater systems resulting in a synthetized map which combines the information in a suitable way.
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Malard, A., Jeannin, P. Y., Weber, E., Vouillamoz, J., Rickerl, D., & Eichenberger, U. (2014). Apport des outils 3D pour la caractérisation des aquifères karstiques: l'approche KARSYS. Karstologia, 2, 31–40.
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Turk, J., Malard, A., Jeannin, P. - Y., Gabrovsek, F., Petric, M., Ravbar, N., et al. (2014). Hydrogeological interpretation of the alpine karst massif by application of a Karsys approach (Kanin case study, Julian Alps). Hydrological Processes, Published online in Wiley Online Library, DOI: 10.1002/hyp.10313.
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