U-Pb Geochronology and Geochemistry of U-Rich Garnet from the Giant Beiya Gold-Polymetallic Deposit in SW China: Constraints on Skarn Mineralization Process
Abstract
:1. Introduction
2. Geological Setting and Ore Geology
2.1. Regional Geology
2.2. Ore Deposit Geology
3. Samples and Analytical Methods
4. Results
4.1. Garnet Petrography
4.2. Major and Trace Elements of Garnet
4.3. Garnet U-Pb Ages
5. Discussion
5.1. Geochronology of the Beiya Garnet
5.2. Metallogenic Implications
6. Conclusions
- (1)
- Two types of U-rich garnet are distinguished from the Beiya skarn ores: Grt I and Grt II. Both Grt I and Grt II are Fe-rich grandites, although Grt II is richer in Fe than Grt I. Grt I and Grt II yield lower intercept U-Pb ages of 35.8 ± 0.8 Ma and 34.0 ± 2.1 Ma, respectively, which is consistent with previous studies within uncertainty and provides a reliable alternative in dating skarn alteration/mineralization.
- (2)
- Trace element characteristics of Grt I and Grt II suggest that from the early to late prograde skarn, the ore-forming fluids may have changed from being relatively reduced and acidic to relatively oxidized and neutral.
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Sample | W297 (Grt I) | |||||||||||||||||||||||
Spot No. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | |||||
SiO2 (wt %) | 38.2 | 37.8 | 38.0 | 38.5 | 38.0 | 37.5 | 37.5 | 37.6 | 38.3 | 37.8 | 37.8 | 38.6 | 38.3 | 37.7 | 38.1 | 39.0 | 38.8 | 39.1 | 39.0 | |||||
Al2O3 | 2.76 | 2.73 | 3.40 | 3.32 | 2.06 | 1.86 | 3.49 | 1.16 | 2.30 | 0.61 | 0.90 | 3.40 | 2.20 | 2.65 | 0.83 | 3.75 | 2.37 | 1.43 | 3.76 | |||||
FeO | 23.9 | 23.8 | 23.0 | 23.4 | 25.0 | 25.0 | 23.0 | 26.1 | 24.8 | 26.3 | 26.4 | 23.4 | 24.1 | 24.1 | 26.4 | 22.9 | 25.0 | 26.0 | 22.8 | |||||
MnO | 0.18 | 0.23 | 0.24 | 0.17 | 0.13 | 0.18 | 0.41 | 0.33 | 0.36 | 0.37 | 0.33 | 0.38 | 0.32 | 0.21 | 0.23 | 0.20 | 0.21 | 0.18 | 0.22 | |||||
MgO | 0.05 | 0.08 | 0.06 | 0.03 | 0.06 | 0.06 | 0.10 | 0.09 | 0.14 | 0.10 | 0.07 | 0.11 | 0.12 | 0.06 | 0.07 | 0.02 | 0.03 | 0.03 | 0.02 | |||||
CaO | 32.4 | 32.3 | 32.7 | 32.6 | 32.2 | 32.6 | 32.3 | 32.0 | 32.2 | 31.7 | 31.6 | 32.3 | 31.9 | 32.4 | 32.1 | 32.6 | 32.1 | 32.4 | 32.3 | |||||
Total | 97.5 | 97.0 | 97.3 | 98.0 | 97.4 | 97.2 | 96.8 | 97.3 | 98.1 | 96.8 | 97.1 | 98.1 | 96.9 | 97.1 | 97.8 | 98.5 | 98.5 | 99.1 | 98.1 | |||||
Cations on the basis of 12 oxygens | ||||||||||||||||||||||||
Si | 3.172 | 3.157 | 3.153 | 3.172 | 3.169 | 3.134 | 3.126 | 3.147 | 3.169 | 3.190 | 3.175 | 3.175 | 3.205 | 3.144 | 3.177 | 3.196 | 3.194 | 3.209 | 3.204 | |||||
Ti | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |||||
Al | 0.270 | 0.269 | 0.332 | 0.323 | 0.202 | 0.183 | 0.343 | 0.115 | 0.224 | 0.061 | 0.089 | 0.330 | 0.217 | 0.260 | 0.082 | 0.362 | 0.230 | 0.139 | 0.364 | |||||
Cr | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | |||||
Fe3+ | 1.385 | 1.418 | 1.361 | 1.333 | 1.459 | 1.548 | 1.405 | 1.591 | 1.438 | 1.560 | 1.561 | 1.319 | 1.374 | 1.453 | 1.565 | 1.247 | 1.383 | 1.444 | 1.228 | |||||
Fe2+ | 0.275 | 0.243 | 0.230 | 0.280 | 0.279 | 0.200 | 0.200 | 0.239 | 0.276 | 0.291 | 0.294 | 0.289 | 0.311 | 0.230 | 0.281 | 0.319 | 0.338 | 0.341 | 0.342 | |||||
Mn | 0.013 | 0.016 | 0.017 | 0.012 | 0.009 | 0.013 | 0.029 | 0.024 | 0.025 | 0.026 | 0.024 | 0.027 | 0.022 | 0.015 | 0.016 | 0.014 | 0.015 | 0.012 | 0.016 | |||||
Mg | 0.006 | 0.010 | 0.007 | 0.004 | 0.007 | 0.007 | 0.013 | 0.011 | 0.017 | 0.013 | 0.008 | 0.013 | 0.015 | 0.008 | 0.009 | 0.003 | 0.003 | 0.003 | 0.003 | |||||
Ca | 2.879 | 2.887 | 2.900 | 2.877 | 2.874 | 2.915 | 2.884 | 2.873 | 2.850 | 2.859 | 2.849 | 2.847 | 2.856 | 2.891 | 2.872 | 2.860 | 2.838 | 2.852 | 2.844 | |||||
Total | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | |||||
Almandine | 8.7 | 7.7 | 7.3 | 8.8 | 8.8 | 6.4 | 6.4 | 7.6 | 8.7 | 9.1 | 9.3 | 9.1 | 9.7 | 7.3 | 8.8 | 10.0 | 10.6 | 10.6 | 10.7 | |||||
Spessartine | 0.4 | 0.5 | 0.5 | 0.4 | 0.3 | 0.4 | 0.9 | 0.8 | 0.8 | 0.8 | 0.7 | 0.8 | 0.7 | 0.5 | 0.5 | 0.4 | 0.5 | 0.4 | 0.5 | |||||
Pyrope | 0.2 | 0.3 | 0.2 | 0.1 | 0.2 | 0.2 | 0.4 | 0.4 | 0.5 | 0.4 | 0.3 | 0.4 | 0.5 | 0.2 | 0.3 | 0.1 | 0.1 | 0.1 | 0.1 | |||||
Grossular | 14.8 | 14.6 | 18.1 | 17.7 | 11.0 | 9.8 | 18.1 | 6.1 | 12.1 | 3.4 | 4.8 | 17.9 | 12.1 | 14.0 | 4.5 | 20.1 | 12.7 | 7.8 | 20.3 | |||||
Andradite | 75.9 | 76.9 | 73.9 | 73.0 | 79.7 | 83.2 | 74.2 | 85.2 | 77.8 | 86.3 | 84.9 | 71.7 | 77.0 | 78.0 | 85.9 | 69.4 | 76.2 | 81.1 | 68.5 | |||||
Sample | W281 (Grt II) | |||||||||||||||||||||||
Spot No. | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
SiO2 (wt %) | 37.3 | 37.7 | 36.7 | 36.5 | 37.1 | 36.5 | 36.7 | 37.0 | 37.6 | 36.9 | 37.8 | 37.9 | 38.3 | 36.8 | 37.3 | 37.0 | 37.2 | 38.1 | 38.0 | 37.7 | 37.8 | 37.2 | 37.4 | 37.0 |
Al2O3 | 5.69 | 3.58 | 1.34 | 2.28 | 1.73 | 1.40 | 1.14 | 3.00 | 5.14 | 2.51 | 3.93 | 4.03 | 5.01 | 1.52 | 2.16 | 2.14 | 2.65 | 4.38 | 5.66 | 4.20 | 5.10 | 0.74 | 1.82 | 0.30 |
FeO | 20.6 | 24.5 | 26.9 | 25.8 | 26.7 | 26.1 | 26.9 | 25.1 | 21.8 | 25.4 | 23.5 | 23.6 | 22.2 | 27.1 | 26.2 | 26.3 | 26.3 | 23.9 | 21.8 | 23.7 | 22.2 | 28.2 | 26.9 | 28.9 |
MnO | 0.37 | 0.37 | 0.31 | 0.18 | 0.17 | 0.20 | 0.15 | 0.17 | 0.25 | 0.37 | 0.28 | 0.32 | 0.29 | 0.33 | 0.28 | 0.32 | 0.27 | 0.37 | 0.46 | 0.34 | 0.47 | 0.29 | 0.28 | 0.23 |
MgO | 0.19 | 0.17 | 0.05 | 0.04 | 0.13 | 0.12 | 0.02 | 0.09 | 0.13 | 0.24 | 0.05 | 0.22 | 0.10 | 0.29 | 0.17 | 0.26 | 0.17 | 0.08 | 0.13 | 0.05 | 0.17 | 0.04 | 0.07 | 0.07 |
CaO | 33.8 | 33.3 | 32.7 | 33.1 | 33.3 | 33.4 | 33.6 | 33.6 | 34.3 | 33.4 | 34.5 | 34.2 | 34.3 | 33.0 | 33.4 | 32.3 | 33.5 | 33.3 | 34.0 | 34.3 | 33.9 | 33.2 | 33.6 | 32.8 |
Total | 98.0 | 99.7 | 98.0 | 97.8 | 99.1 | 97.7 | 98.5 | 98.9 | 99.3 | 98.8 | 100.0 | 100.2 | 100.3 | 99.0 | 99.5 | 98.3 | 100.1 | 100.1 | 100.1 | 100.3 | 99.7 | 99.6 | 100.0 | 99.2 |
Cations on the basis of 12 oxygens | ||||||||||||||||||||||||
Si | 3.044 | 3.059 | 3.053 | 3.027 | 3.041 | 3.037 | 3.034 | 3.025 | 3.038 | 3.025 | 3.043 | 3.042 | 3.068 | 3.023 | 3.041 | 3.057 | 3.018 | 3.065 | 3.045 | 3.026 | 3.040 | 3.053 | 3.043 | 3.054 |
Ti | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
Al | 0.546 | 0.342 | 0.131 | 0.223 | 0.167 | 0.137 | 0.111 | 0.290 | 0.489 | 0.243 | 0.373 | 0.382 | 0.473 | 0.147 | 0.207 | 0.209 | 0.253 | 0.416 | 0.534 | 0.397 | 0.484 | 0.072 | 0.174 | 0.029 |
Cr | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 |
Fe3+ | 1.365 | 1.541 | 1.763 | 1.722 | 1.750 | 1.788 | 1.822 | 1.660 | 1.436 | 1.707 | 1.542 | 1.535 | 1.392 | 1.806 | 1.710 | 1.678 | 1.710 | 1.454 | 1.376 | 1.551 | 1.436 | 1.821 | 1.740 | 1.863 |
Fe2+ | 0.042 | 0.121 | 0.109 | 0.069 | 0.084 | 0.031 | 0.039 | 0.055 | 0.038 | 0.036 | 0.043 | 0.050 | 0.094 | 0.058 | 0.083 | 0.140 | 0.071 | 0.156 | 0.081 | 0.041 | 0.061 | 0.113 | 0.090 | 0.130 |
Mn | 0.026 | 0.025 | 0.022 | 0.013 | 0.012 | 0.014 | 0.010 | 0.012 | 0.017 | 0.026 | 0.019 | 0.022 | 0.019 | 0.023 | 0.019 | 0.022 | 0.019 | 0.025 | 0.031 | 0.023 | 0.032 | 0.020 | 0.019 | 0.016 |
Mg | 0.023 | 0.021 | 0.007 | 0.005 | 0.016 | 0.015 | 0.003 | 0.010 | 0.016 | 0.029 | 0.006 | 0.026 | 0.012 | 0.036 | 0.021 | 0.032 | 0.021 | 0.010 | 0.016 | 0.006 | 0.020 | 0.004 | 0.008 | 0.008 |
Ca | 2.953 | 2.892 | 2.916 | 2.941 | 2.929 | 2.977 | 2.982 | 2.948 | 2.966 | 2.933 | 2.974 | 2.944 | 2.942 | 2.906 | 2.919 | 2.862 | 2.908 | 2.874 | 2.917 | 2.956 | 2.927 | 2.916 | 2.926 | 2.900 |
Total | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 | 8.000 |
Almandine | 1.4 | 3.9 | 3.6 | 2.3 | 2.8 | 1.0 | 1.3 | 1.8 | 1.3 | 1.2 | 1.4 | 1.6 | 3.1 | 1.9 | 2.7 | 4.6 | 2.3 | 5.1 | 2.7 | 1.4 | 2.0 | 3.7 | 2.9 | 4.2 |
Spessartine | 0.8 | 0.8 | 0.7 | 0.4 | 0.4 | 0.5 | 0.3 | 0.4 | 0.6 | 0.9 | 0.6 | 0.7 | 0.6 | 0.8 | 0.6 | 0.7 | 0.6 | 0.8 | 1.0 | 0.8 | 1.0 | 0.7 | 0.6 | 0.5 |
Pyrope | 0.8 | 0.7 | 0.2 | 0.2 | 0.5 | 0.5 | 0.1 | 0.3 | 0.5 | 1.0 | 0.2 | 0.9 | 0.4 | 1.2 | 0.7 | 1.0 | 0.7 | 0.3 | 0.5 | 0.2 | 0.7 | 0.1 | 0.3 | 0.3 |
Grossular | 27.7 | 17.2 | 6.6 | 11.1 | 8.4 | 7.0 | 5.6 | 14.5 | 24.8 | 12.1 | 19.0 | 19.3 | 24.3 | 7.3 | 10.4 | 10.4 | 12.4 | 20.9 | 26.8 | 19.9 | 24.3 | 3.6 | 8.7 | 1.5 |
Andradite | 69.3 | 77.4 | 88.9 | 86.0 | 87.9 | 91.0 | 92.7 | 83.0 | 72.8 | 84.9 | 78.7 | 77.5 | 71.6 | 88.9 | 85.6 | 83.3 | 83.9 | 72.9 | 69.0 | 77.7 | 72.0 | 91.9 | 87.4 | 93.5 |
Point | Y | La | Ce | Pr | Nd | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | Th | U | ΣREE | LREE | HREE | LREE/HREE 1 | δEu 2 | Th/U |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Grt I | |||||||||||||||||||||||
W297-3 | 1.35 | 8.37 | 61.8 | 7.36 | 17.1 | 0.95 | 1.05 | 0.57 | 0.06 | 0.23 | 0.04 | 0.08 | 0.00 | 0.07 | 0.01 | 1.90 | 23.8 | 97.6 | 96.6 | 1.05 | 91.7 | 4.0 | 0.08 |
W297-4 | 1.73 | 13.8 | 92.3 | 9.25 | 18.2 | 0.94 | 1.01 | 0.59 | 0.06 | 0.24 | 0.05 | 0.11 | 0.01 | 0.11 | 0.01 | 2.59 | 25.3 | 137 | 135 | 1.18 | 115 | 3.8 | 0.10 |
W297-5 | 1.70 | 17.2 | 88.1 | 7.35 | 12.6 | 0.75 | 0.79 | 0.46 | 0.03 | 0.22 | 0.03 | 0.09 | 0.02 | 0.09 | 0.01 | 1.71 | 39.3 | 128 | 127 | 0.95 | 133 | 3.8 | 0.04 |
W297-6 | 0.83 | 17.1 | 100.3 | 9.46 | 17.2 | 0.72 | 0.98 | 0.44 | 0.03 | 0.15 | 0.03 | 0.08 | 0.01 | 0.03 | 0.01 | 2.48 | 38.3 | 147 | 146 | 0.79 | 185 | 4.9 | 0.06 |
W297-7 | 0.60 | 17.8 | 82.0 | 6.18 | 10.3 | 0.49 | 0.78 | 0.25 | 0.02 | 0.10 | 0.03 | 0.05 | 0.00 | 0.02 | 0.01 | 0.81 | 45.0 | 118 | 118 | 0.47 | 249 | 6.0 | 0.02 |
W297-8 | 1.69 | 9.60 | 65.5 | 7.37 | 16.0 | 0.77 | 0.98 | 0.59 | 0.05 | 0.29 | 0.05 | 0.12 | 0.02 | 0.11 | 0.02 | 2.06 | 24.5 | 101 | 100 | 1.25 | 79.9 | 4.3 | 0.08 |
W297-9 | 1.31 | 13.5 | 78.5 | 7.20 | 14.6 | 0.77 | 0.95 | 0.52 | 0.03 | 0.20 | 0.04 | 0.08 | 0.00 | 0.07 | 0.00 | 1.76 | 32.4 | 116 | 115 | 0.95 | 122 | 4.3 | 0.05 |
W297-10 | 1.07 | 21.2 | 102 | 8.17 | 14.3 | 0.73 | 0.83 | 0.49 | 0.04 | 0.17 | 0.05 | 0.07 | 0.01 | 0.09 | 0.01 | 1.45 | 38.2 | 148 | 147 | 0.93 | 159 | 4.0 | 0.04 |
W297-11 | 0.75 | 23.4 | 102 | 6.48 | 9.86 | 0.47 | 0.61 | 0.29 | 0.03 | 0.11 | 0.03 | 0.05 | 0.01 | 0.03 | 0.01 | 1.47 | 51.5 | 143 | 143 | 0.56 | 256 | 4.7 | 0.03 |
W297-12 | 1.68 | 16.1 | 96.2 | 9.38 | 19.4 | 0.98 | 1.12 | 0.63 | 0.06 | 0.30 | 0.05 | 0.09 | 0.02 | 0.08 | 0.01 | 3.06 | 37.1 | 144 | 143 | 1.23 | 116 | 4.1 | 0.08 |
W297-13 | 1.96 | 16.6 | 86.5 | 6.88 | 12.6 | 0.79 | 0.85 | 0.49 | 0.07 | 0.28 | 0.04 | 0.13 | 0.01 | 0.13 | 0.00 | 1.66 | 39.9 | 125 | 124 | 1.16 | 107 | 3.9 | 0.04 |
W297-14 | 1.05 | 17.7 | 80.3 | 6.04 | 10.04 | 0.73 | 0.78 | 0.33 | 0.03 | 0.14 | 0.03 | 0.07 | 0.01 | 0.04 | 0.01 | 0.98 | 49.8 | 116 | 116 | 0.64 | 179 | 4.2 | 0.02 |
W297-15 | 1.40 | 20.8 | 111 | 9.05 | 14.9 | 0.68 | 0.75 | 0.51 | 0.05 | 0.17 | 0.04 | 0.06 | 0.02 | 0.06 | 0.01 | 2.49 | 46.1 | 158 | 157 | 0.92 | 171 | 3.7 | 0.05 |
W297-16 | 1.12 | 28.5 | 103 | 7.04 | 11.2 | 0.66 | 0.66 | 0.44 | 0.03 | 0.14 | 0.02 | 0.08 | 0.01 | 0.04 | 0.01 | 1.28 | 64.0 | 152 | 151 | 0.78 | 194 | 3.5 | 0.02 |
W297-17 | 1.61 | 16.8 | 99.7 | 9.42 | 17.8 | 0.89 | 0.87 | 0.49 | 0.06 | 0.30 | 0.05 | 0.09 | 0.01 | 0.09 | 0.01 | 3.29 | 38.2 | 147 | 146 | 1.10 | 133 | 3.7 | 0.09 |
W297-18 | 2.36 | 8.11 | 58.5 | 7.32 | 17.9 | 1.20 | 1.24 | 0.64 | 0.06 | 0.42 | 0.07 | 0.11 | 0.02 | 0.12 | 0.01 | 2.81 | 25.5 | 95.8 | 94.3 | 1.46 | 64.7 | 3.9 | 0.11 |
W297-19 | 1.68 | 11.7 | 67.8 | 7.01 | 14.1 | 0.95 | 1.04 | 0.55 | 0.05 | 0.23 | 0.04 | 0.08 | 0.01 | 0.09 | 0.01 | 2.64 | 39.9 | 104 | 103 | 1.05 | 97.5 | 4.0 | 0.07 |
W297-20 | 1.26 | 17.8 | 80.6 | 6.36 | 11.7 | 0.71 | 0.82 | 0.40 | 0.06 | 0.20 | 0.03 | 0.06 | 0.01 | 0.06 | 0.00 | 1.81 | 50.9 | 119 | 118 | 0.82 | 144 | 4.3 | 0.04 |
W297-21 | 2.39 | 10.9 | 66.0 | 7.42 | 18.5 | 1.12 | 1.31 | 0.72 | 0.07 | 0.37 | 0.07 | 0.20 | 0.02 | 0.07 | 0.01 | 2.06 | 26.1 | 107 | 105 | 1.54 | 68.3 | 4.2 | 0.08 |
W297-22 | 1.31 | 22.4 | 89.4 | 6.67 | 11.6 | 0.86 | 0.77 | 0.40 | 0.03 | 0.23 | 0.03 | 0.05 | 0.01 | 0.06 | 0.01 | 1.31 | 55.0 | 133 | 132 | 0.82 | 161 | 3.5 | 0.02 |
W297-23 | 1.71 | 12.9 | 71.4 | 6.62 | 13.9 | 0.81 | 0.94 | 0.50 | 0.05 | 0.27 | 0.04 | 0.12 | 0.01 | 0.11 | 0.01 | 1.92 | 36.0 | 108 | 107 | 1.11 | 95.9 | 4.2 | 0.05 |
W297-24 | 2.93 | 14.3 | 77.0 | 7.14 | 15.4 | 0.99 | 1.13 | 0.79 | 0.09 | 0.38 | 0.08 | 0.23 | 0.03 | 0.17 | 0.02 | 2.33 | 31.0 | 118 | 116 | 1.79 | 64.8 | 3.8 | 0.08 |
W297-25 | 2.15 | 18.0 | 80.1 | 6.17 | 10.8 | 0.81 | 0.85 | 0.48 | 0.07 | 0.28 | 0.06 | 0.13 | 0.01 | 0.09 | 0.01 | 2.25 | 47.2 | 118 | 117 | 1.14 | 103 | 3.8 | 0.05 |
Grt II | |||||||||||||||||||||||
W281-1 | 10.7 | 15.3 | 89.3 | 12.7 | 45.7 | 4.35 | 1.57 | 3.60 | 0.40 | 2.27 | 0.41 | 1.11 | 0.16 | 1.19 | 0.18 | 13.7 | 14.3 | 178 | 169 | 9.32 | 18.1 | 1.2 | 0.96 |
W281-2 | 9.15 | 13.3 | 80.7 | 11.5 | 41.4 | 4.26 | 1.52 | 2.97 | 0.38 | 2.14 | 0.38 | 0.95 | 0.14 | 1.03 | 0.16 | 10.3 | 12.1 | 161 | 153 | 8.15 | 18.7 | 1.2 | 0.85 |
W281-3 | 3.33 | 16.8 | 96.4 | 13.9 | 49.3 | 3.91 | 1.72 | 1.90 | 0.16 | 0.69 | 0.14 | 0.30 | 0.05 | 0.37 | 0.04 | 22.1 | 12.0 | 186 | 182 | 3.65 | 49.9 | 1.7 | 1.84 |
W281-4 | 1.86 | 9.63 | 54.5 | 7.23 | 23.5 | 1.82 | 0.71 | 1.00 | 0.08 | 0.46 | 0.07 | 0.18 | 0.03 | 0.19 | 0.03 | 6.54 | 6.12 | 99.5 | 97.5 | 2.03 | 48.1 | 1.5 | 1.07 |
W281-6 | 0.31 | 12.1 | 67.0 | 8.35 | 21.6 | 0.80 | 0.36 | 0.44 | 0.02 | 0.07 | 0.01 | 0.03 | 0.00 | 0.03 | 0.00 | 4.80 | 8.19 | 111 | 110 | 0.61 | 179 | 1.7 | 0.59 |
W281-7 | 0.40 | 14.3 | 95.6 | 13.4 | 38.5 | 1.50 | 0.56 | 0.73 | 0.03 | 0.13 | 0.01 | 0.04 | 0.00 | 0.05 | 0.01 | 8.97 | 9.51 | 165 | 164 | 0.99 | 165 | 1.5 | 0.94 |
W281-8 | 0.30 | 15.8 | 105 | 15.2 | 47.0 | 2.14 | 0.90 | 0.78 | 0.03 | 0.06 | 0.01 | 0.02 | 0.01 | 0.02 | 0.00 | 13.5 | 10.8 | 187 | 186 | 0.93 | 200 | 1.7 | 1.25 |
W281-9 | 1.16 | 14.2 | 95.6 | 14.4 | 48.4 | 2.49 | 1.15 | 0.93 | 0.05 | 0.25 | 0.03 | 0.09 | 0.01 | 0.08 | 0.01 | 11.1 | 7.73 | 178 | 176 | 1.45 | 121 | 1.9 | 1.44 |
W281-10 | 27.0 | 6.47 | 37.0 | 6.71 | 32.2 | 5.17 | 1.55 | 4.82 | 0.74 | 4.72 | 0.99 | 2.94 | 0.44 | 2.81 | 0.41 | 5.69 | 7.72 | 107 | 89.0 | 17.9 | 4.98 | 0.9 | 0.74 |
W281-11 | 19.5 | 5.14 | 32.6 | 5.97 | 25.7 | 4.20 | 1.33 | 3.96 | 0.57 | 3.45 | 0.74 | 1.97 | 0.27 | 2.10 | 0.28 | 3.56 | 6.34 | 88.3 | 75.0 | 13.3 | 5.62 | 1.0 | 0.56 |
W281-12 | 11.1 | 3.98 | 31.1 | 5.40 | 22.9 | 3.43 | 1.14 | 2.94 | 0.40 | 2.16 | 0.39 | 1.12 | 0.15 | 1.01 | 0.17 | 3.10 | 5.46 | 76.3 | 68.0 | 8.34 | 8.15 | 1.1 | 0.57 |
W281-13 | 4.02 | 12.3 | 77.7 | 11.7 | 41.3 | 3.13 | 1.33 | 1.74 | 0.16 | 0.84 | 0.15 | 0.41 | 0.05 | 0.42 | 0.05 | 11.9 | 9.32 | 151 | 147 | 3.82 | 38.6 | 1.6 | 1.28 |
W281-14 | 0.56 | 19.1 | 77.1 | 6.88 | 14.1 | 0.72 | 0.39 | 0.43 | 0.03 | 0.12 | 0.03 | 0.06 | 0.01 | 0.06 | 0.01 | 3.46 | 7.56 | 119 | 118 | 0.75 | 157 | 2.0 | 0.46 |
W281-15 | 5.25 | 12.1 | 28.6 | 2.05 | 7.49 | 1.13 | 0.33 | 1.19 | 0.15 | 1.03 | 0.19 | 0.53 | 0.08 | 0.49 | 0.06 | 0.89 | 2.95 | 55.4 | 51.7 | 3.72 | 13.9 | 0.9 | 0.30 |
W281-18 | 3.75 | 16.4 | 107 | 13.8 | 39.1 | 2.52 | 0.77 | 1.46 | 0.16 | 0.79 | 0.13 | 0.25 | 0.04 | 0.28 | 0.04 | 6.21 | 5.85 | 183 | 180 | 3.14 | 57.3 | 1.1 | 1.06 |
W281-19 | 12.9 | 23.7 | 46.6 | 5.07 | 19.6 | 3.22 | 0.82 | 2.84 | 0.41 | 2.40 | 0.47 | 1.24 | 0.15 | 1.18 | 0.14 | 1.18 | 5.15 | 108 | 99.0 | 8.84 | 11.2 | 0.8 | 0.23 |
W281-20 | 11.0 | 12.3 | 40.0 | 5.13 | 20.4 | 3.54 | 1.10 | 3.22 | 0.40 | 2.21 | 0.37 | 0.98 | 0.13 | 0.97 | 0.14 | 3.25 | 5.07 | 90.8 | 82.4 | 8.40 | 9.8 | 1.0 | 0.64 |
W281-21 | 18.5 | 45.7 | 77.4 | 6.65 | 22.8 | 4.40 | 1.01 | 4.36 | 0.63 | 3.63 | 0.69 | 1.72 | 0.24 | 1.59 | 0.21 | 1.90 | 9.98 | 171 | 158 | 13.1 | 12.1 | 0.7 | 0.19 |
W281-22 | 9.05 | 12.6 | 38.8 | 4.64 | 17.7 | 2.89 | 0.96 | 2.57 | 0.33 | 1.81 | 0.29 | 0.84 | 0.12 | 0.79 | 0.10 | 2.36 | 4.74 | 84.4 | 77.6 | 6.85 | 11.3 | 1.1 | 0.50 |
W281-25 | 20.7 | 71.5 | 92.9 | 6.59 | 23.1 | 4.90 | 1.02 | 4.49 | 0.68 | 3.77 | 0.73 | 1.90 | 0.27 | 1.65 | 0.21 | 2.08 | 10.5 | 214 | 200 | 13.7 | 14.6 | 0.7 | 0.20 |
W281-26 | 2.19 | 14.9 | 74.6 | 10.8 | 39.5 | 3.43 | 1.67 | 1.37 | 0.12 | 0.46 | 0.06 | 0.18 | 0.02 | 0.16 | 0.02 | 10.5 | 7.27 | 147 | 145 | 2.39 | 60.5 | 2.0 | 1.45 |
W281-27 | 8.75 | 41.5 | 72.0 | 5.81 | 19.8 | 3.26 | 0.89 | 2.23 | 0.33 | 1.70 | 0.29 | 0.74 | 0.11 | 0.64 | 0.09 | 7.12 | 9.68 | 149 | 143 | 6.15 | 23.3 | 1.0 | 0.74 |
W281-28 | 8.25 | 60.8 | 89.2 | 6.15 | 18.7 | 2.74 | 0.84 | 2.35 | 0.31 | 1.55 | 0.32 | 0.74 | 0.09 | 0.68 | 0.08 | 0.99 | 10.3 | 185 | 178 | 6.13 | 29.1 | 1.0 | 0.10 |
W281-29 | 0.83 | 18.3 | 92.6 | 12.5 | 45.2 | 3.15 | 1.77 | 1.04 | 0.06 | 0.27 | 0.04 | 0.08 | 0.01 | 0.04 | 0.00 | 13.2 | 9.08 | 175 | 174 | 1.55 | 112 | 2.4 | 1.45 |
W281-30 | 2.82 | 49.3 | 81.5 | 5.96 | 16.5 | 1.61 | 0.56 | 1.17 | 0.11 | 0.55 | 0.10 | 0.22 | 0.03 | 0.23 | 0.03 | 1.22 | 10.4 | 158 | 155 | 2.43 | 64.0 | 1.2 | 0.12 |
Point | 207Pb/206Pb | 207Pb/235U | 206Pb/238U | |||
---|---|---|---|---|---|---|
Ratio | 1sigma | Ratio | 1sigma | Ratio | 1sigma | |
Grt I | ||||||
W297-1-03 | 0.1078 | 0.0149 | 0.0900 | 0.0092 | 0.0061 | 0.0002 |
W297-1-04 | 0.1300 | 0.0320 | 0.1100 | 0.0128 | 0.0061 | 0.0003 |
W297-1-05 | 0.0898 | 0.0147 | 0.0725 | 0.0102 | 0.0059 | 0.0002 |
W297-1-06 | 0.2506 | 0.0294 | 0.2385 | 0.0267 | 0.0069 | 0.0002 |
W297-1-07 | 0.1167 | 0.0261 | 0.0969 | 0.0110 | 0.0060 | 0.0003 |
W297-1-09 | 0.0931 | 0.0215 | 0.0765 | 0.0075 | 0.0060 | 0.0002 |
W297-1-10 | 0.0973 | 0.0206 | 0.0838 | 0.0090 | 0.0062 | 0.0002 |
W297-1-11 | 0.1006 | 0.0260 | 0.0800 | 0.0087 | 0.0058 | 0.0002 |
W297-1-12 | 0.1081 | 0.0196 | 0.0880 | 0.0082 | 0.0059 | 0.0002 |
W297-1-14 | 0.2618 | 0.0338 | 0.2555 | 0.0166 | 0.0071 | 0.0003 |
W297-1-15 | 0.2181 | 0.0372 | 0.2062 | 0.0213 | 0.0069 | 0.0004 |
W297-1-17 | 0.2804 | 0.0417 | 0.3148 | 0.0260 | 0.0081 | 0.0003 |
W297-1-20 | 0.1042 | 0.0201 | 0.0879 | 0.0086 | 0.0061 | 0.0002 |
W297-1-21 | 0.1747 | 0.0347 | 0.1617 | 0.0162 | 0.0067 | 0.0003 |
W297-1-25 | 0.0889 | 0.0169 | 0.0758 | 0.0105 | 0.0062 | 0.0002 |
W297-1-26 | 0.1029 | 0.0145 | 0.0899 | 0.0083 | 0.0063 | 0.0002 |
W297-1-27 | 0.6246 | 0.0376 | 1.7264 | 0.1087 | 0.0200 | 0.0010 |
W297-1-28 | 0.1993 | 0.0226 | 0.1787 | 0.0258 | 0.0065 | 0.0004 |
W297-1-30 | 0.4950 | 0.0379 | 0.9488 | 0.0404 | 0.0139 | 0.0004 |
W297-1-31 | 0.4569 | 0.0366 | 0.7666 | 0.0457 | 0.0122 | 0.0005 |
Grt II | ||||||
W281-1-01 | 0.2996 | 0.0477 | 0.3466 | 0.0393 | 0.0084 | 0.0004 |
W281-1-04 | 0.4768 | 0.0564 | 0.8491 | 0.0814 | 0.0129 | 0.0007 |
W281-1-08 | 0.7728 | 0.0410 | 6.4467 | 0.2126 | 0.0605 | 0.0016 |
W281-1-09 | 0.7856 | 0.0415 | 7.1790 | 0.4840 | 0.0663 | 0.0040 |
W281-1-12 | 0.6480 | 0.0563 | 2.5820 | 0.2228 | 0.0289 | 0.0020 |
W281-1-13 | 0.7230 | 0.0618 | 2.8244 | 0.1252 | 0.0283 | 0.0010 |
W281-1-14 | 0.1749 | 0.0372 | 0.1563 | 0.0318 | 0.0065 | 0.0004 |
W281-1-15 | 0.3994 | 0.0484 | 0.5604 | 0.0444 | 0.0102 | 0.0005 |
W281-1-18 | 0.5441 | 0.0541 | 1.1597 | 0.0768 | 0.0155 | 0.0008 |
W281-1-21 | 0.7054 | 0.0631 | 3.4552 | 0.2264 | 0.0355 | 0.0019 |
W281-1-23 | 0.7634 | 0.0560 | 6.2413 | 0.3263 | 0.0593 | 0.0026 |
W281-1-24 | 0.1625 | 0.0217 | 0.1367 | 0.0202 | 0.0061 | 0.0003 |
W281-1-25 | 0.6523 | 0.0392 | 1.4804 | 0.2499 | 0.0165 | 0.0019 |
W281-1-26 | 0.5611 | 0.0586 | 1.0598 | 0.0635 | 0.0137 | 0.0006 |
W281-1-27 | 0.1607 | 0.0234 | 0.1272 | 0.0306 | 0.0057 | 0.0004 |
W281-1-29 | 0.6043 | 0.0660 | 1.1606 | 0.0680 | 0.0139 | 0.0007 |
© 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
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Fu, Y.; Sun, X.; Li, D.; Lin, H. U-Pb Geochronology and Geochemistry of U-Rich Garnet from the Giant Beiya Gold-Polymetallic Deposit in SW China: Constraints on Skarn Mineralization Process. Minerals 2018, 8, 128. https://doi.org/10.3390/min8040128
Fu Y, Sun X, Li D, Lin H. U-Pb Geochronology and Geochemistry of U-Rich Garnet from the Giant Beiya Gold-Polymetallic Deposit in SW China: Constraints on Skarn Mineralization Process. Minerals. 2018; 8(4):128. https://doi.org/10.3390/min8040128
Chicago/Turabian StyleFu, Yu, Xiaoming Sun, Dengfeng Li, and Hai Lin. 2018. "U-Pb Geochronology and Geochemistry of U-Rich Garnet from the Giant Beiya Gold-Polymetallic Deposit in SW China: Constraints on Skarn Mineralization Process" Minerals 8, no. 4: 128. https://doi.org/10.3390/min8040128