Geochemical Zonation

Below the suboxic zone, sulfate reduction is the main pathway of organic carbon oxidation and 

Methane producing microorganisms are even more strongly inhibited and, although present throughout the entire sediment deposit, methane does not exceed a trace concentration of 0.2 pM. 

Most of the known dissimilatory sulfate reducers are bacteria, but also some thermophilic archaea belong to this group (Rabus et al. 2004 Stetter et al. 1993). For an overview of the most 

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Most SEDEX deposits are not precipitated directly adjacent to their feeder zone (Sangster 2002) therefore the geochemical zonation of distal products provides a valuable exploration tool. Manganese halos have been well documented for the Tynagh mine in... 

Roberts S. and Ruiz J. (1989) Geochemical zonation and evolution of the lower crust in Mexico. J. Geophys. Res. 94, 7961-7974. 

Initial conditions were specified to reflect site conditions in 1994 when a major field sampling program took place (Zhu et al., 2002). The domain was divided into four zones (Figure 10.4), reflecting groundwater geochemical zonations observed in the field (Zhu et al., 2002). The pore fluid chemistry and aquifer mineral compositions for each zone are shown in the phreeqc input file (Table 10.3). 

Fig. 5.11 Pathways of organic carbon degradation in marine sediments and their relation to the geochemical zonations and the consumption of oxidants. (After Fenchel and Jorgensen 1977).

Park, J., R. A. Sanford and C. M. Bethke, 2006, Geochemical and microbiological zonation of the Middendorf aquifer, South Carolina. Chemical Geology 230, 88-104. 

Morganti, J.M. (1983). Zonation of chalcofile elements about the Howard s Pass (XY) Zn-Pb deposit, Selwyn Basin. Journal of Geochemical Exploration, 19, 503-542. Mann, A.W., Birrell, R.D., Mann, A.T., Humphreys, D. B., Perdrix, J.L (1998). Application of the mobile metal ion technique to routine geochemical exploration. Journal of Geochemical Exploration, 61 87-102. Morganti, J. M. (1979). The geology and ore deposits of the Howards Pass Area, Yukon and Northwest Territories the origin of basinal sedimentary stratiform sulphide deposits. Unpublished PhD thesis, University of British Columbia. 

Goodfellow, W.D., Jonasson, l.R. and Morganti, J.M., 1983. Zonation of chalcophile elements about the Howards Pass (XY) Zn-Pb deposit, Selwyn Basin, Yukon. J. Geochem. Explor., 19 503-542. 

Figure 13.15 Schematic cross-section of an idealized uranium roll-front orebody showing the zonation of elements and primary hydrologic and geochemical features. Oxidized groundwaters flow from left to right. The roll front and associated redox interface moves in the same direction. After Larson (1978).

Mozley, P.S. (1989b) Complex compositional zonation in concretionary siderite implications for geochemical studies. J. sediment. Petrol., 59, 815-818. 

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