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Table 1 Minerals and exchangers considered in the model

From: The element-release mechanisms of two pyrite-bearing siliciclastic rocks from the North German Basin at temperatures up to 90 °C under oxic and anoxic conditions

Phase Composition Mass fraction,  % Reactive surface, m2/g
Sample I Sample II Sample I Sample II
Quartz SiO 2 95 39 0.002 0.02
Amorphous silica SiO2 (amorph) 0.0001 0.0009 300 300
Potassium feldspar KAlSi 3 O 8 2 8 0.0023 0.023
Kaolinite Al2Si2O5(OH)4 1 37 3.6 3.6
Muscovite KAl3Si3O10(OH)2 1 12 1.2 1.2
Calcite CaCO3 0 0.2 0 0.0001
Pyrite FeS2 0.005 0.29 0.003 0.001
Ferrihydrite Fe(OH)3 (amorph) 0.007 0.26 n.a. n.a.
Aluminum hydroxide Al(OH)3 (amorph) 0.0013 0.02 n.a. n.a.
Manganese oxohydroxide MnOOH 0.0007 0.0004 n.a. n.a.
Al exchange AlX3 7.3 × 10−5 2.6 × 10−4 n.a. n.a.
Ca exchange CaX2 3.8 × 10−3 0.3 n.a. n.a.
Mn exchange MnX2 8.4 × 10−5 6.4 × 10−4 n.a. n.a.
  1. Phases printed in italics were excluded after sensitivity analysis or initial simulations. Mass fractions were taken from Müller et al. (2017), except amorphous aluminum hydroxide, which was calculated from sequential extraction data (ibid.). Reactive surfaces were calculated from specific surface values collected in the RES3T database
  2. Phases printed in italics were excluded after sensitivity analysis or initial simulations