1994 Arctic Ocean Section
at least the upper 3040 cm. No evidence is present for lowered redox condi-
tions, which would support dramatic solubilization of iron or manganese.
Silicate concentrations were elevated over bottom water contents by only 20
30 M/L. Measurements of titration alkalinity show concentrations within
the sediments to be higher than those in the bottom waters.
The oxygen gradients will be used to calculate the oxygen fluxes into the
sediments. As this flux is driven by the oxidation of organic matter, rates of
carbon oxidation will be calculated. The alkalinity of the pore waters was in-
creased over bottom water concentrations due to either organic matter oxida-
tion or dissolution of solid-phase carbonate. Fluxes of titration alkalinity out
of the sediments can be compared with fluxes of oxygen to evaluate the relative
importance of these two reactions. Thus, the pore-water profiles will allow us
to estimate the rates of carbon oxidation and carbonate dissolution within
these sediments. In conjunction with estimates of burial and productivity, the
results regarding the rates of organic matter oxidation and carbonate dissolu-
tion will be useful in constructing a present-day carbon budget for the central
Arctic Basin.
54
Previous Page
