Diffusion coefficients in nearshore marine sediments1

The formation resistivity factor, F , necessary to calculate bulk sediment diffusion coefficients of interstitial solutes from free solution diffusion coefficients, can be estimated from ϕ , the sediment porosity. Empirical relationships between F and ϕ indicate that F ≈ ϕ −2 for unlithified marine sands or muds when ϕ ≲ 0.7 and F ≈ ϕ − 2.5 to ϕ −3 for high porosity muds when ϕ ≳ 0.7.