1. We have carried out for the first time, evaporation studies on a 2D micro-model based on a thin section of a carbonate (dolomite) rock. 2. For deionised water, we observed the three classical periods of evaporation expected from earlier drying experiments in porous media; the CRP, FRP and RFP. 3. For brines, we observed that the length of the CRP decreased with increasing brine concentration and became almost non-existent for saturated brine. Dry pore area (equivalent to mass lost by evaporation) became linear with the square root of time after a short CRP. 4. This behavior is not due to capillary disconnection from the evaporating surface (because salt continued to deposit at the surface during this time) as usually the case for deionised water. 5. We propose that this behavior is likely due to salt deposited in the fracture channel and matrix below it greatly impeding hydraulic connectivity, lower vapour pressure of brines, and the relatively high viscosity of brines increasing viscous resistance to flow.
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