Table 3 Representative EMPA data of chlorite.
Analytical points | H1_4 | H1_5 | H1_8 | H1_13 | H1_14 | H1_15 | H1_18 | H1_19 | H1_20 | H1_21 | H1_22 | H1_23 | H1_24 | H1_25 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Composition (wt.%) | ||||||||||||||
SiO2 | 32.89 | 32.68 | 33.05 | 31.42 | 31.07 | 31.40 | 30.77 | 30.96 | 32.18 | 30.98 | 31.58 | 31.66 | 31.54 | 32.33 |
TiO2 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.71 | 0.07 | 0.32 | 0.00 | 0.00 | 0.00 | 0.00 |
Al2O3 | 12.55 | 12.54 | 12.74 | 9.30 | 9.95 | 9.55 | 9.10 | 8.78 | 10.46 | 10.14 | 9.92 | 9.92 | 10.68 | 10.44 |
Cr2O3 | 0.00 | 0.00 | 0.06 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
FeO | 13.36 | 12.86 | 12.76 | 20.87 | 19.50 | 19.35 | 20.33 | 20.62 | 18.66 | 18.69 | 19.71 | 18.59 | 16.88 | 17.49 |
MnO | 0.46 | 0.43 | 0.46 | 0.21 | 0.24 | 0.22 | 0.19 | 0.14 | 0.23 | 0.22 | 0.20 | 0.27 | 0.21 | 0.23 |
MgO | 25.10 | 25.48 | 24.57 | 23.88 | 23.64 | 25.01 | 24.32 | 24.03 | 24.09 | 24.80 | 24.06 | 23.91 | 25.25 | 24.73 |
CaO | 0.72 | 0.70 | 0.72 | 0.28 | 0.29 | 0.24 | 0.25 | 0.73 | 0.44 | 0.49 | 0.39 | 0.86 | 0.26 | 0.32 |
Na2O | 0.11 | 0.13 | 0.13 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.14 | 0.00 | 0.00 |
K2O | 0.41 | 0.30 | 0.29 | 0.00 | 0.00 | 0.28 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
H2O (calc.) | 11.83 | 11.80 | 11.78 | 11.47 | 11.34 | 11.55 | 11.38 | 11.40 | 11.58 | 11.51 | 11.49 | 11.42 | 11.52 | 11.58 |
Totals | 97.44 | 96.91 | 96.55 | 97.44 | 96.02 | 97.58 | 96.36 | 97.37 | 97.69 | 97.15 | 97.33 | 96.77 | 96.34 | 97.10 |
apfu based on 14 oxygen equivalents | ||||||||||||||
Si | 3.33 | 3.32 | 3.37 | 3.29 | 3.29 | 3.26 | 3.24 | 3.26 | 3.33 | 3.23 | 3.30 | 3.32 | 3.28 | 3.35 |
AlIV | 0.67 | 0.68 | 0.63 | 0.71 | 0.71 | 0.74 | 0.76 | 0.74 | 0.67 | 0.77 | 0.70 | 0.68 | 0.72 | 0.65 |
AlVI | 0.83 | 0.82 | 0.90 | 0.43 | 0.53 | 0.43 | 0.37 | 0.35 | 0.61 | 0.47 | 0.52 | 0.55 | 0.59 | 0.62 |
Ti | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.06 | 0.01 | 0.03 | 0.00 | 0.00 | 0.00 | 0.00 |
Cr | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Fe3+ | 0.00 | 0.00 | 0.00 | 0.22 | 0.12 | 0.22 | 0.33 | 0.12 | 0.00 | 0.14 | 0.10 | 0.00 | 0.07 | 0.00 |
Fe2+ | 1.13 | 1.09 | 1.09 | 1.61 | 1.60 | 1.46 | 1.46 | 1.70 | 1.62 | 1.49 | 1.62 | 1.63 | 1.40 | 1.52 |
Mn | 0.04 | 0.04 | 0.04 | 0.02 | 0.02 | 0.02 | 0.02 | 0.01 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 |
Mg | 3.79 | 3.86 | 3.73 | 3.72 | 3.73 | 3.87 | 3.82 | 3.77 | 3.72 | 3.85 | 3.74 | 3.74 | 3.92 | 3.82 |
Σ Octahedral cations | 5.80 | 5.82 | 5.76 | 6.00 | 6.00 | 6.00 | 6.00 | 6.00 | 5.97 | 6.00 | 6.00 | 5.95 | 6.00 | 5.98 |
□ | 0.20 | 0.18 | 0.24 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.03 | 0.00 | 0.00 | 0.05 | 0.00 | 0.02 |
Ca | 0.0786 | 0.08 | 0.08 | 0.03 | 0.03 | 0.03 | 0.03 | 0.08 | 0.05 | 0.05 | 0.04 | 0.10 | 0.03 | 0.04 |
Na | 0.0214 | 0.03 | 0.02 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.03 | 0.00 | 0.00 |
K | 0.0529 | 0.04 | 0.04 | 0.00 | 0.00 | 0.04 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Σ Interlayer cations | 0.15 | 0.14 | 0.14 | 0.03 | 0.03 | 0.06 | 0.03 | 0.08 | 0.05 | 0.05 | 0.04 | 0.13 | 0.03 | 0.04 |
R2+ | 4.97 | 4.99 | 4.86 | 5.35 | 5.35 | 5.35 | 5.30 | 5.48 | 5.36 | 5.36 | 5.38 | 5.40 | 5.34 | 5.35 |
Mg# | 0.77 | 0.78 | 0.77 | 0.70 | 0.70 | 0.73 | 0.72 | 0.69 | 0.70 | 0.72 | 0.70 | 0.70 | 0.74 | 0.72 |
Temperature [°C]24 | 152 | 156 | 142 | 168 | 168 | 176 | 182 | 177 | 153 | 187 | 164 | 156 | 169 | 148 |
Temperature [°C]25 | 155 | 157 | 148 | 165 | 165 | 170 | 174 | 171 | 155 | 177 | 163 | 157 | 165 | 152 |
