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Häuselmann, P., Jeannin, P. Y., & Monbaron, M. (2003). Role of epiphreatic flow and soutirages in conduit morphogenesis: the Bärenschacht example (BE, Switzerland). Zeitschrift für Geomorphologie, NF, 47(2), 171–190.
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Häuselmann, P., Otz, M., & Jeannin, P. - Y. (2003). A review of dye tracing experiments done in the Siebenhengste karst region (Bern, Switzerland). Eclogae geol. Helv., 96, 23–36.
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Perrin, J., Jeannin, P. Y., & Zwahlen, F. (2003). Epikarst storage in a karst aquifere : a conceptual model based on isotopic data, Milandre test site, Switzerland. Journal of Hydrology, 279, 106–124.
Résumé: The Milandre test site is a karst aquifer characterized by diffuse infiltration, a well developed conduit network, and several tributaries feeding an underground river. Field data include discharge rate measurements, stable isotopes, weekly rainfall and spring-water isotope sampling, and detailed isotope sampling during three flood events. Flood sampling was carried out at several tributaries corresponding to conduit flow, vadose flow and seepage flow. Weekly sampling showed a strong buffering of the rainfall isotopic signal at the spring. This attenuation suggests an important mixing reservoir in the system. Flood events showed highly peaking hydraulic responses but buffered rain isotope responses. These results indicate that the soil and epikarst sub-systems have an important storage capacity. A conceptual model of flow and transport in the soil and epikarst zone is proposed: Soil plays an important role in mixing due to the presence of capillary water storage. Consequently dampened concentrations reach the epikarst despite a rapid hydraulic response. The epikarst acts as the storage element and distributes water as either a base flow component or a quick flow component. When recharge exceeds a given threshold, excess infiltrated water bypasses the soil and epikarst and reaches the saturated zone as fresh flow. Based on this model, the significance of phreatic storage is thought to be limited, at least in Milandre test site. Hence the saturated zone is seen mainly as a transmissive zone through its well developed conduit network. q 2003 Elsevier B.V. All rights reserved.
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Perrin, J., Jeannin, P. Y., & Zwahlen, F. (2003). Implications of the spatial variability of infiltration-water chemistry for the investigation of a karst aquifer: a field study at Milandre test site, Swiss Jura. Hydrogeology Journal, 11, 673–686.
Résumé: The Milandre test site is an ideal karstic aquifer for studying the spatial heterogeneity of groundwater chemistry. Numerous observation points can be sampled: the spring, the underground river and its tributaries, and boreholes at different depths. The main causes of the spatial variability of the chemical parameters are: nature and localisation of the input, the structure of the infiltration zone, chemical reactions (transit time vs. reaction kinetics) and mixing of different waters. Physico-chemical data on springs discharging from the karstic system represent the sum of this spatial heterogeneity. Therefore, it is difficult to interpret the global-chemical response with a simple mixing model of the aquifer subsystems (runoff, matrix reservoir, epikarst). Chemical constituents related to agricultural inputs show important seasonal variations (coefficient of variation approximately 15%) and parameters linked to rainfall (delta(18)O) and to the aquifer (Ca2+, HCO3-) present variations of less than 5%. This result indicates the importance of water storage in the epikarstic aquifer for periods of a few months
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Lacave, C., Koller, M. W., Eichenberger, U., & Jeannin, P. Y. (2003). Prevention of speleothem rupture during nearby construction. Environmental Geology, 43, 892–900.
Résumé: The cave of Milandre, located in the Swiss Jura, is characterised by a rich speleothem population. Some of the most decorated galleries lie at low depth, (40-50 m). A new highway will be built, with a tunnel, just over a decorated part of the cave. In order to prevent damage in the cave, a study was conducted in the,framework of the impact study. One of the goals was to evaluate the risk of speleothem rupture caused by explosive shots that will be used to excavate the tunnel portal. To this end, the speleothems' vulnerability to ground shaking was compared with the observed accelerations induced by experimental explosions. This procedure allowed to determine maximum acceptable explosive charges
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Kovács, A., & Jeannin, P. - Y. (2003). Hydrogeological overview of the Bure plateau, Ajoie, Switzerland. Eclogae geol. Helv., 96, 367–379.
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Häuselmann, P. (2003). Cross-formational flow, diffluence and transfluence observed in St. Beatus Cave and Sieben Hengste (Switzerland). Speleogenesis and Evolution of Karst Aquifers, 1(2), 1–5.
Résumé: Observations in St. Beatus Cave and neighbouring caves revealed complex water flow paths that can be used for explaining the behaviour of tracing experiments. The observations prove that even in vadose conditions, cross-formational flow, diffluences and transfluences are a quite common feature. Therefore, also karst in the vadose zone has a very complex organisation.
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Grasso, A., Jeannin, P. - Y., & Zwahlen, F. (2003). A deterministic approach to the coupled analysis of karsts springs' hydrographs and chemographs. Journal of Hydrology, 271, 65–76.
Résumé: During the chemically based recession flow phase of karstic springs the carbonate (dissolved limestone) concentration can be expressed as negative power of the flow rate. The empirically determined Conc/Q relationship allows two parameters (a and A) to be defined, of which one (a ) depends on the geometric dimensions of the saturated (submerged) karstic network. In this paper we present a deterministic model which simulates the concentration of carbonate at the outlet of a network of circular rectilinear conduits as a function of flow rate. This model, based on hydraulic principles and the calcite dissolution kinetics, allows the sensitivity of the a and A parameters to be studied under different chemical, physical and geometric scenarios. Simulation results show that A is a function of the calcite saturation concentration, whereas a depends on the spatial dimensions of the karstic network (void length and aperture). The deterministic model results were applied to real karstic systems to evaluate the geometric dimensions of submerged karstic networks. q 2002 Elsevier Science B.V. All rights reserved.
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Rotzer, S., Blant, D., Hapka, R., & Taillard, E. (2003). Spéléologie dans la cluse de Pertuis. Cavernes, 47-1, 3–22.
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