Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 12 6 2008 10.5194/hess-12-1285-2008 http://www.hydrol-earth-syst-sci.net/12/1285/2008/ http://www.hydrol-earth-syst-sci.net/12/1285/2008/hess-12-1285-2008.html http://www.hydrol-earth-syst-sci.net/12/1285/2008/hess-12-1285-2008.pdf 1285 1293 2008-12-01 Infiltrative instability near topography with implication for the drainage of soluble rocks P. Genthon pierre.genthon@ird.ne A. Ormond Paléotropique, IRD, BP A5 98848 Nouméa, New Caledonia DTP, Obs. Midi Pyrénées, Toulouse, France now at: HydroSciences, IRD BP11416 Niamey, Niger We present here numerical modeling of infiltration instability near a topographic edge of a water-saturated porous slice by analogy with a limestone formation devoid of initial heterogeneities such as fractures faults or joints and limited by a vertical cliff. In our runs a first dissolution finger develops near the cliff edge, and ends to intersect it above its mid height. 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