Mn, Cu, and Pb were measured in pore waters at a site in the Caribou sub-basin, Lake Superior. The pore water profiles show evidence for the post-depositional mobility of the metals, consistent with interpretations made from sediment concentration profiles. The pore water and sediment concentration profiles of Mn appear to be diagenetically linked. Diagenetic modeling results indicate that the measured profiles are not in a steady-state relationship. The cause of the non-steady-state conditions is unclear but may be related to recent changes in sedimentation rates and in Mn oxidation rates. Flux estimates for Cu and Pb show that these metals could be diffusing from the sediment to overlying water. The decomposition of organic matter is suggested as a source for the metals. A significant amount of Cu and Pb brought to the sediment surface during sedimentation appears to be recycled to the pore waters. This suggests that concentration profiles of these metals in the sediment may not be reliable indicators of the timing and amounts of anthropogenic metal input in Lake Superior. (Author's abstract)
RECORD ID: 8911187
F&G CODE: 02h; 02j; 05b
Publication
McKee, J.D., Wilson, T.P., Long, D.T. and Owen, R.M., Pore Water Profiles and
Early Diagenesis of Mn, Cu, and Pb in Sediments from Large Lakes: Journal of
Great Lakes Research JGLRDE; Vol. 15, No. 1, p 68-83, 1989. 9 fig, 5 tab, 32
ref. NOAA Office of Sea Grant, grant NA86AA-D-SG043, EPA contract CR813535-01-1.
Back to USGS, WRD Michigan Home Page
U.S. Department of the
Interior, U.S. Geological
Survey
Maintainer: Webmaster
<gs-w-milns_webmaster@usgs.gov>
Updated On: Wednesday, September 27, 2000
Privacy Statement ||
Disclaimer
URL: http://mi.water.usgs.gov/reports/Long3.html