In Situ Measurements of Pore Water Diffusion Coefficients Using Tritiated Water
- 29 February 1980
- journal article
- research article
- Published by Canadian Science Publishing in Canadian Journal of Fisheries and Aquatic Sciences
- Vol. 37 (3) , 545-551
- https://doi.org/10.1139/f80-069
Abstract
In situ diffusion coefficients in the pore waters of Lake 227 were measured by monitoring the movement of tritiated water into the pore waters. The diffusion coefficients were determined by analytical and numerical modeling of the tritium profiles. During the summer, tritiated water diffuses into the sediment by molecular diffusion and this process is well approximated by a constant diffusivity model. The summer coefficients for diffusion were 1–2 × 10−5 cm2∙s−1 at a water depth of 1.5 m (20 °C) and 0.3–0.8 × 10−6 cm2∙s−1 at 8.75 m (4 °C). During fall overturn, clear evidence was found for enhanced mixing of pore waters to a sediment depth of 10 cm at water depths of 0.75 and 3.85 m. This enhanced mixing was not accompanied by mixing of the solid phase of the sediments.Key words: sediments, pore water, diffusion coefficients, tritium, lake sedimentsThis publication has 0 references indexed in Scilit: