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Table 1 Isotopic compositions of calcites and CO2 content in the Ongeluk basaltic andesites and hydrothermal jaspilites

From: Weak hydrothermal carbonation of the Ongeluk volcanics: evidence for low CO2 concentrations in seawater and atmosphere during the Paleoproterozoic global glaciation

Sample no. Rock type Classification of calcite CO2 (wt%) δ13C (VPDB, ‰) δ18O (VPDB, ‰) Temperature (°C)a
GU033 Basaltic andesite Disseminated 0 − 14.2 − 15.2 123
GU034 Basaltic andesite Disseminated 0 − 15.6 − 13.8 109
GU035 Basaltic andesite Disseminated 0 − 13.2 − 14.6 117
GU036 Basaltic andesite Disseminated 0.01 − 15.8 − 15.8 130
GU037 Basaltic andesite Disseminated 0.01 − 16.1 − 14.3 114
GU038 Basaltic andesite Disseminated 0 − 15.9 − 12.9 100
GU041 Basaltic andesite Disseminated 0 − 18.9 − 14.1 112
GU045 Basaltic andesite Disseminated 0 − 18.3 − 13.3 104
GU048 Basaltic andesite Disseminated 0 − 15.7 − 13.2 103
GU049 Basaltic andesite Disseminated 0 − 14.9 − 14.6 117
GU054 Basaltic andesite Disseminated 0 − 23.5 − 14.3 114
GU055 Basaltic andesite Disseminated 0.01 − 24.9 − 15 121
GU063 Basaltic andesite Disseminated 0 − 22.3 − 12.3 94
GU110 Pillowed basaltic andesite (core) Disseminated 0 − 15.6 − 10.2 77
GU172 Basaltic andesite Disseminated 0 − 18.0 − 10.8 82
GU174 Basaltic andesite with calcite veins Disseminated/vein 0.060 − 16.1 − 17.1 147
GU144 Interpillow jaspilite 0 − 17.0 − 17.6 153
GU149 Interpillow jaspilite 0 − 21.3 − 13.4 105
GU151 Interpillow jaspilite 0.01 − 31.9 − 17.9 158
GU150 Interpillow jaspilite with calcite/quartz veins 0.1 − 15.4 − 17.7 155
GU158 Brecciated interpillow jaspilite 0.05 − 12.5 − 17.8 156
  1. aFormation temperature was estimated from the reported oxygen fractionation factor (O’Neil et al. 1969; Friedman and O’Neil 1977; Chacko et al. 2001) assuming a fluid with δ18O = 0‰ (SMOW)