OXYGEN PENETRATION DEPTHS AND FLUXES IN MARINE-SEDIMENTS

A compilation of numerous studies of oxygen profiles in marine sedimen ts and estimated fluxes across the sediment-water interface supports t he existence of a simple relationship between oxygen penetration depth (L), benthic oxygen flux (F-O2(0)), and bottom water oxygen concentra tion([O-2](BW)). This relationship is: L = 2 phi D-s [O-2](BW)/F-O2(0) , where phi and D-s are the porosity and diffusivity of O-2 in sedimen t, respectively. The relationship holds well for continental margin en vironments, but not in open ocean basins. The success of this simple r elationship in describing continental margin field data suggests that the pore water profiles are at steady state, the depth distribution an d reactivity of organic carbon is nearly uniform, and pore water irrig ation is generally negligible. This work also demonstrates the consist ency of the data recently collected by several independent works.