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Zupan Hajna, 2003
Incomplete Solution: Weathering of Cave Walls and the Production, Transport and Deposition of Carbonate Fines
Zalozba ZRC Publications, Carsologica Series
Order No./Bestell Nr./Art. No.: 35885
The main topic of this monograph is the weathering of carbonate rocks on the walls of cave passages. Of particular interest were the characteristics and peculiarities of the limestone and dolomite weathering processes, the type of solution and why all of the carbonate rock does not dissolve immediately. The results of incomplete solution of carbonate rock are weathered zones that remain on the cave passage walls. The most are weathered cave passage walls soaked by percolation water at the contact with sediments and walls exposed to condensation corrosion. On cave passage walls strongly weathered limestone and dolomite remain only where they are protected from further dissolution and mechanical erosion.
During weathering the rock gradually discolours and by increased porosity looses its mechanical strength. Mineral and chemical composition of the weathered zone is almost identical to composition of parent rock, yet it is much more porous. Soluble remain of the incomplete limestone solution is opposed to general theories of karst origin as they accepted the opinion that limestone dissolves if affected by aggressive solution. In described cases an incomplete dissolution may just prepare the carbonate rock for the mechanical transport of its weathered particles by the flowing water. The transported carbonate particles of silt or clay size may accumulate in the cave passages as clastic cave sediments. In any case the speed of water flow must correspond to the rate of weathering in order to tear exposed particles from the rock surface.