Assessment of doline geometry using geophysics on the Quercy plateau karst (South France) |
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| Authors: | Rémi Valois Christian Camerlynck Amine Dhemaied Roger Guerin Gaghik Hovhannissian Valérie Plagnes Faycal Rejiba Henri Robain |
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| Institution: | 1. Université Pierre et Marie Curie‐Paris 6, , 75252 Paris cedex 05, France;2. Institut de Recherche pour le Développement, , Bondy Cedex, France |
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| Abstract: | In the protection of karstic aquifers, the role played by dolines is of interest as these shallow structures can be preferential infiltration pathways for groundwater recharge. In this study, three depressions in South France (Orniac, Lot) were identified and characterized using combined geophysical methods. Apparent conductivity mapping allows precise definition of dolines corresponding to topographic depressions. It also reveals other dolines that are hidden by soil cover. Electrical resistivity and seismic refraction tomography provide detailed cross‐sections. Even though the dolines studied are close one to another, they exhibit great variability in shape and content. Moreover, time‐lapse data show that the most saturated regions are on the edges of the first doline. Such information helps to evaluate human impacts and forecast potential groundwater contamination. Copyright © 2011 John Wiley & Sons, Ltd. |
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| Keywords: | electrical resistivity tomography seismic refraction tomography sinkhole electromagnetic survey Quercy plateau karst |
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