Research Article
Petrogenesis of Quaternary Shoshonitic Volcanism in NE Iran (Ardabil): Implication for Postcollisional Magmatism
Table 1
Composition of clinopyroxene, plagioclase, and glass shards in the Sabalan volcanic rocks.
(a) |
| Name | S2 | S2 | S5 | S5 | S5 | S9 | S9 | S9 | S9 | S9 | S4 | S4 | S4 | Mineral | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx | Cpx |
| SiO2 | 53.16 | 52.94 | 51.33 | 52.40 | 52.56 | 50.13 | 52.32 | 51.67 | 52.81 | 50.47 | 50.64 | 52.66 | 52.16 | TiO2 | 0.82 | 0.47 | 0.76 | 0.95 | 0.42 | 0.80 | 0.46 | 0.71 | 0.55 | 0.95 | 0.59 | 0.28 | 0.45 | Al2O3 | 2.22 | 1.99 | 2.44 | 2.52 | 1.34 | 2.67 | 1.22 | 1.93 | 1.11 | 2.10 | 2.78 | 2.71 | 2.51 | Cr2O3 | 0.14 | 0.00 | 0.31 | 0.00 | 0.16 | 0.00 | 0.00 | 0.02 | 0.00 | 0.00 | 0.02 | 0.72 | 0.18 | FeO* | 8.26 | 8.94 | 8.74 | 8.93 | 9.47 | 8.80 | 9.07 | 8.38 | 8.86 | 9.44 | 8.39 | 6.36 | 6.46 | MnO | 0.37 | 0.74 | 0.57 | 0.51 | 0.59 | 0.55 | 0.36 | 0.19 | 0.53 | 0.42 | 0.36 | 0.31 | 0.21 | MgO | 15.07 | 15.01 | 14.67 | 14.29 | 14.84 | 14.87 | 14.78 | 15.19 | 15.39 | 15.35 | 15.37 | 16.60 | 16.81 | CaO | 20.05 | 19.37 | 19.80 | 19.93 | 19.70 | 20.10 | 19.16 | 20.51 | 20.12 | 20.06 | 20.24 | 19.60 | 20.19 | Na2O | 0.46 | 0.46 | 0.59 | 0.45 | 0.49 | 0.37 | 0.34 | 0.46 | 0.42 | 0.68 | 0.32 | 0.38 | 0.40 | K2O | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.02 | 0.01 | 0.05 | 0.03 | 0.05 | 0.05 | 0.01 | 0.07 | NiO | 0.07 | 0.19 | 0.00 | 0.03 | 0.00 | 0.00 | 0.00 | 0.01 | 0.18 | 0.03 | 0.06 | 0.08 | 0.00 | BaO | 0.28 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.21 | 0.00 | 0.00 | 0.00 | 0.00 | 0.43 | 0.14 | F | 0.00 | 0.00 | 0.00 | 0.25 | 0.08 | 0.00 | 0.12 | 0.00 | 0.16 | 0.12 | 0.00 | 0.04 | 0.00 | Cl | 0.00 | 0.00 | 0.02 | 0.05 | 0.09 | 0.00 | 0.00 | 0.00 | 0.00 | 0.05 | 0.03 | 0.00 | 0.00 |
| Total | 100.89 | 100.10 | 99.23 | 100.32 | 99.74 | 98.31 | 98.05 | 99.11 | 100.14 | 99.70 | 98.83 | 100.18 | 99.57 |
| Mg# | 0.76 | 0.75 | 0.75 | 0.74 | 0.74 | 0.75 | 0.74 | 0.76 | 0.76 | 0.74 | 0.77 | 0.82 | 0.82 | Cr# | 0.04 | 0.00 | 0.08 | 0.00 | 0.07 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.15 | 0.04 |
| En | 0.44 | 0.44 | 0.43 | 0.43 | 0.43 | 0.43 | 0.44 | 0.44 | 0.44 | 0.44 | 0.44 | 0.48 | 0.48 | Fs | 0.14 | 0.15 | 0.15 | 0.15 | 0.15 | 0.14 | 0.15 | 0.14 | 0.14 | 0.15 | 0.14 | 0.10 | 0.10 | Wo | 0.42 | 0.41 | 0.42 | 0.43 | 0.41 | 0.42 | 0.41 | 0.43 | 0.42 | 0.41 | 0.42 | 0.41 | 0.42 |
| Si | 1.95 | 1.96 | 1.93 | 1.94 | 1.97 | 1.90 | 1.98 | 1.94 | 1.96 | 1.90 | 1.91 | 1.94 | 1.93 | Ti | 0.02 | 0.01 | 0.02 | 0.03 | 0.01 | 0.02 | 0.01 | 0.02 | 0.02 | 0.03 | 0.02 | 0.01 | 0.01 | Al | 0.10 | 0.09 | 0.11 | 0.11 | 0.06 | 0.12 | 0.05 | 0.09 | 0.05 | 0.09 | 0.12 | 0.12 | 0.11 | Cr | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.02 | 0.01 | Fe* | 0.25 | 0.28 | 0.27 | 0.28 | 0.30 | 0.28 | 0.29 | 0.26 | 0.28 | 0.30 | 0.26 | 0.20 | 0.20 | Mn | 0.01 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.01 | 0.01 | 0.02 | 0.01 | 0.01 | 0.01 | 0.01 | Mg | 0.83 | 0.83 | 0.82 | 0.79 | 0.83 | 0.84 | 0.83 | 0.85 | 0.85 | 0.86 | 0.86 | 0.91 | 0.93 | Ca | 0.79 | 0.77 | 0.80 | 0.79 | 0.79 | 0.82 | 0.78 | 0.82 | 0.80 | 0.81 | 0.82 | 0.77 | 0.80 | Na | 0.03 | 0.03 | 0.04 | 0.03 | 0.04 | 0.03 | 0.03 | 0.03 | 0.03 | 0.05 | 0.02 | 0.03 | 0.03 | K | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | Ni | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.01 | 0.00 | 0.00 | 0.00 | 0.00 |
| Total | 3.99 | 4.00 | 4.02 | 3.99 | 4.01 | 4.03 | 3.99 | 4.02 | 4.01 | 4.05 | 4.03 | 4.00 | 4.02 |
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(b) |
| Name | S2 | S2 | S2 | S9 | S9 | S9 | S9 | S5 | S5 | S4 | S4 | S4 | Mineral | Plag | Plag | Plag | Plag | Plag | Plag | Plag | Plag | Plag | Plag | Plag | Plag |
| SiO2 | 56.984 | 57.374 | 57.797 | 58.691 | 58.503 | 58.330 | 55.219 | 51.093 | 50.666 | 52.338 | 52.592 | 55.365 | TiO2 | 0.162 | 0.067 | 0.080 | 0.080 | 0.117 | 0.052 | 0.073 | 0.073 | 0.022 | 0.058 | 0.000 | 0.022 | Al2O3 | 26.210 | 26.159 | 25.617 | 25.602 | 24.411 | 23.408 | 26.422 | 29.910 | 29.617 | 28.542 | 28.959 | 27.208 | Cr2O3 | 0.000 | 0.063 | 0.000 | 0.032 | 0.000 | 0.000 | 0.032 | 0.000 | 0.114 | 0.032 | 0.000 | 0.292 | FeO | 0.542 | 0.593 | 0.683 | 0.450 | 0.536 | 0.400 | 0.596 | 0.533 | 0.938 | 0.691 | 0.517 | 1.065 | MnO | 0.061 | 0.000 | 0.000 | 0.087 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | MgO | 0.028 | 0.017 | 0.013 | 0.007 | 0.023 | 0.023 | 0.040 | 0.030 | 0.101 | 0.061 | 0.055 | 0.088 | CaO | 8.802 | 8.795 | 7.656 | 7.085 | 7.094 | 7.526 | 9.544 | 12.947 | 12.451 | 12.060 | 12.005 | 9.777 | Na2O | 5.583 | 5.826 | 6.191 | 6.558 | 6.683 | 6.862 | 5.769 | 4.245 | 3.722 | 4.808 | 4.873 | 5.364 | K2O | 0.942 | 1.006 | 1.203 | 1.083 | 1.341 | 1.443 | 0.918 | 0.261 | 0.255 | 0.425 | 0.313 | 0.597 | NiO | 0.000 | 0.041 | 0.041 | 0.000 | 0.055 | 0.000 | 0.000 | 0.136 | 0.000 | 0.055 | 0.000 | 0.150 | BaO | 0.000 | 0.000 | 0.143 | 0.215 | 0.358 | 0.000 | 0.071 | 0.071 | 0.215 | 0.071 | 0.144 | 0.071 | F | 0.000 | 0.000 | 0.000 | 0.205 | 0.041 | 0.123 | 0.124 | 0.168 | 0.000 | 0.000 | 0.000 | 0.083 | Cl | 0.000 | 0.016 | 0.005 | 0.000 | 0.026 | 0.032 | 0.016 | 0.000 | 0.068 | 0.000 | 0.011 | 0.032 |
| Total | 99.314 | 99.955 | 99.430 | 100.095 | 99.189 | 98.199 | 98.824 | 99.466 | 98.169 | 99.141 | 99.469 | 100.115 |
| An% | 46.560 | 45.482 | 40.596 | 37.384 | 36.972 | 37.737 | 47.760 | 62.762 | 64.896 | 58.091 | 57.653 | 50.181 |
| Si | 2.582 | 2.587 | 2.618 | 2.639 | 2.662 | 2.680 | 2.535 | 2.350 | 2.358 | 2.409 | 2.409 | 2.511 | Ti | 0.006 | 0.002 | 0.003 | 0.003 | 0.004 | 0.002 | 0.003 | 0.003 | 0.001 | 0.002 | 0.000 | 0.001 | Al | 1.400 | 1.390 | 1.368 | 1.357 | 1.309 | 1.267 | 1.430 | 1.621 | 1.624 | 1.548 | 1.563 | 1.454 | Cr | 0.000 | 0.002 | 0.000 | 0.001 | 0.000 | 0.000 | 0.001 | 0.000 | 0.004 | 0.001 | 0.000 | 0.010 | Fe* | 0.021 | 0.022 | 0.026 | 0.017 | 0.020 | 0.015 | 0.023 | 0.021 | 0.037 | 0.027 | 0.020 | 0.040 | Mn | 0.002 | 0.000 | 0.000 | 0.003 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | Mg | 0.002 | 0.001 | 0.001 | 0.000 | 0.002 | 0.002 | 0.003 | 0.002 | 0.007 | 0.004 | 0.004 | 0.006 | Ca | 0.427 | 0.425 | 0.372 | 0.341 | 0.346 | 0.370 | 0.469 | 0.638 | 0.621 | 0.595 | 0.589 | 0.475 | Na | 0.491 | 0.509 | 0.544 | 0.572 | 0.590 | 0.611 | 0.514 | 0.379 | 0.336 | 0.429 | 0.433 | 0.472 | K | 0.054 | 0.058 | 0.070 | 0.062 | 0.078 | 0.085 | 0.054 | 0.015 | 0.015 | 0.025 | 0.018 | 0.035 | Ni | 0.000 | 0.001 | 0.001 | 0.000 | 0.002 | 0.000 | 0.000 | 0.005 | 0.000 | 0.002 | 0.000 | 0.005 |
| Total | 4.985 | 4.998 | 5.002 | 4.996 | 5.013 | 5.032 | 5.031 | 5.034 | 5.003 | 5.042 | 5.035 | 5.009 |
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(c) |
| Name | S2 | S2 | S5 | S5 | S9 | S9 | S9 | S4 | S4 | Mineral | Glass | Glass | Glass | Glass | Glass | Glass | Glass | Glass | Glass |
| SiO2 | 75.32 | 75.748 | 73.41 | 74.528 | 68.305 | 72.28 | 66.705 | 72.307 | 72.793 | TiO2 | 0.829 | 0.827 | 0.807 | 0.756 | 0.212 | 0.952 | 0.33 | 1.113 | 1.146 | Al2O3 | 12.863 | 12.567 | 14.018 | 14.063 | 17.432 | 13.495 | 18.55 | 14.152 | 14.029 | Cr2O3 | 0.064 | 0.048 | 0.032 | 0.032 | 0.032 | 0.114 | 0 | 0 | 0.08 | FeO | 0.773 | 1.853 | 0.773 | 0.732 | 0.578 | 1.4 | 0.908 | 1.424 | 2.7 | MnO | 0 | 0 | 0.009 | 0.043 | 0.094 | 0 | 0 | 0 | 0.035 | MgO | 0.041 | 0.041 | 0.003 | 0.025 | 0.036 | 0.051 | 0.046 | 0.051 | 0.065 | CaO | 0.315 | 0.259 | 0.186 | 0.259 | 1.087 | 0.316 | 2.163 | 0.327 | 0.227 | Na2O | 2.599 | 2.205 | 2.536 | 2.99 | 5.346 | 3.317 | 6.42 | 2.062 | 2.092 | K2O | 6.125 | 7.171 | 7.93 | 8.169 | 6.145 | 5.993 | 3.645 | 7.377 | 5.853 | NiO | 0 | 0.027 | 0 | 0 | 0.055 | 0.041 | 0 | 0.055 | 0 | BaO | 0 | 0 | 0.071 | 0 | 0.644 | 0 | 0 | 0 | 0 | F | 0.21 | 0 | 0.042 | 0 | 0.041 | 0.376 | 0.285 | 0 | 0 | Cl | 0.203 | 0.117 | 0.096 | 0.074 | 0.058 | 0.165 | 0.085 | 0.159 | 0.042 |
| Total | 99.343 | 100.863 | 99.727 | 101.671 | 100.065 | 98.5 | 99.139 | 99.028 | 99.063 |
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: Mg number, : total iron.
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