The positive feedback between the rate of flow, the rate of chemical reaction, and the change in permeability accelerates the dissolution processes and might result in the "reactive infiltration instability" which is manifested in "fingers" of cavities, into which fluid is channeled, and salt is dissolved. The spacing between the sinkholes and the rate of their creation is controlled by several factors including: incoming groundwater flux, the salinity of the incoming groundwater, the rate of dissolution, the effective specific surface area, the permeability of the salt and clay layers, the permeability-porosity relation, the dispersivity, and the thickness of the layers.
Shalev, E., V. Lyakhovsky, and Y. Yechieli, Salt dissolution and sinkhole formation along the Dead Sea shore, J Geophys. Res., 111, B03102, doi:10.1029/2005JB004038, 2006.
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Simulated growth of underground voids as a result of dissolution.