Parameters used in calculations
|
Site 1234
|
Site 1235
|
---|---|---|
|
|
|
Average porosity, ![]() |
0.65 | 0.65 |
Diffusivity, Ds, (m2/day)* | 5.0 x 10–5 | 5.0 x 10–5 |
Sediment accumulation rate, ws, m/day | 2.15 x 10–6 | 1.9 x 10–6 |
Pore fluid burial rate, wpw, m/day | 1.33 x 10–6 | 1.9 x 10–6 |
Peclet number = Ds x ![]() |
0.42 | 0.23 |
![]() |
0.065 | 0.02 |
Calculated fluxes | ||
JA2 – JA1 | 0.019 | 0.015 |
JD2 – JD1 | 0.006 | 0.003 |
Total ammonium production flux, PN | 0.025 | 0.018 |
Total Norg flux at 1.45 mcd** | 0.131 | 0.097 |
Fraction buried below zone of active diagenesis†† |
81% ± 10% |
82% ± 10% |
Notes: Fluxes are in mmol/m2 x d. * = Ds = Dm/[1 – ln(2)] (Boudreau, 1997; Li and Gregory, 1974); Dm = molecular diffusivity. † = K = 1.3, ammonium partition coefficient (Berner, 1980), dimensionless. ‡ =
= 1/e-folding distance for ammonium profiles. ** = TNorg flux = PN + TNorg at the bottom of active diagenesis zone; TNorg = TN x 0.8, since adsorbed ammonium is 20% of TN. †† = The uncertainty is based on assumed porosity uncertainty of 5%.