Special Section: Chapman Conference on Hydrogeochemical Responses of Forested Catchments
Influence of Temperature and Mineral Surface Characteristics on Feldspar Weathering Rates in Natural and Artificial Systems: A First Approximation
Article first published online: 9 JUL 2010
Copyright 1990 by the American Geophysical Union.
Water Resources Research
Volume 26, Issue 12, pages 3049–3053, December 1990
How to Cite
1990), Influence of Temperature and Mineral Surface Characteristics on Feldspar Weathering Rates in Natural and Artificial Systems: A First Approximation, Water Resour. Res., 26(12), 3049–3053, doi:10.1029/WR026i012p03049.(
- Issue published online: 9 JUL 2010
- Article first published online: 9 JUL 2010
- Manuscript Accepted: 6 JUL 1990
- Manuscript Received: 14 NOV 1989
Rates of alkali feldspar hydrolysis in the near-neutral pH range are up to 3 orders of magnitude slower in natural systems than in laboratory experiments. Correcting for differences in temperature between natural weathering and laboratory systems reduces the disparity by as much as a factor of 5. Any remaining disparity can be accounted for by differences in the ratio of effective surface area to total surface area; the ratio of effective-to-total surface area in natural systems is generally considerably smaller than in laboratory systems. This may be related, at least in part, to experimental preparation artifacts and to the fact that naturally weathered feldspars have lost much of their most reactive surface to the formation of etch pits. Hydrological factors such as inhomogeneous access of percolating fluids to mineral surfaces may also reduce the proportion of mineral surface area reacting in natural systems.