DYNAMIKA A MECHANISMUS INTERAKCE ALBIT-VODA ZA NORMÁLNÍCH PODMÍNEK
Roč.17,č.1-2(2010)
The aim of this work was to contribute to better understanding of feldspar weathering under surface conditions. Laboratory experiments were focused on dissolution stoichiometry and fluxes of single species into solution as a function of dissolution stages. The fluxes of Na and Al from feldspar exceeded that one of Si during the early stages. During the more advanced stages, the Na-fluxes was lower than the both Al- and Si-fluxes. Finally, the fluxes of individual species were nearly consistent with bulk feldspar stoichiometry. A conceptual dissolution model was proposed, based on three processes: (1) extremely fast hydrolysis of Na-O bonds, (2) fast hydrolysis of Al-O bonds, and (3) slow hydrolysis of Si–O bonds. All the processes run concurrently, but one of them can dominate during different dissolution stages, based on instantaneous activities of single species (number of accessible bonds) on mineral surface.
feldspar; dissolution; flux; model; stoichiometry; weathering
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