The Geochronology and Geochemistry of Zircon as Evidence for the Reconcentration of REE in the Triassic Period in the Chungju Area, South Korea
Abstract
1. Introduction
2. Geological Setting
3. Methods
3.1. EPMA
3.2. LA-ICP-MS
3.3. Laser Ablation Multi-Collector (LA-MC)-ICP-MS
4. Results
4.1. Quartz–Allanite Vein and Zircon Occurrence in the Gyemyeongsan Formation
4.2. Geochronology
4.3. Zircon Composition
5. Discussion and Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Non Correction Ratio | Anderson Correction Age [25] | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
No. | U (ppm) | Th (ppm) | Pb (ppm) | Th/U | 238Pb/206U | 2σ | 207Pb/206Pb | 2σ | 206Pb/238U | 2σ |
1 | 462 | 715 | 232 | 1.43 | 14.938750 | 0.071413 | 0.062570 | 0.000810 | 412.6 | 2.3 |
2 | 407 | 145 | 14 | 0.36 | 32.000000 | 0.399360 | 0.052200 | 0.001400 | 196.4 | 2.7 |
3 | 434 | 238 | 66 | 0.53 | 20.833330 | 0.520833 | 0.065000 | 0.001700 | 299.2 | 8.0 |
4 | 116 | 80 | 9 | 0.68 | 24.740230 | 0.232590 | 0.050900 | 0.002500 | 254.1 | 2.4 |
5 | 113 | 57 | 6 | 0.51 | 25.214320 | 0.292451 | 0.050600 | 0.003100 | 250.9 | 2.9 |
6 | 286 | 126 | 29 | 0.42 | 22.558090 | 0.432537 | 0.059300 | 0.001200 | 275.1 | 5.4 |
7 | 411 | 596 | 223 | 1.40 | 16.528930 | 0.273205 | 0.089000 | 0.001200 | 362.2 | 6.3 |
8 | 229 | 103 | 17 | 0.45 | 24.119630 | 0.378142 | 0.060700 | 0.002300 | 256.9 | 3.5 |
9 | 175 | 250 | 12 | 0.88 | 26.917900 | 0.688345 | 0.053600 | 0.002500 | 235.2 | 6.5 |
10 | 266 | 74 | 9 | 0.26 | 26.518160 | 0.246125 | 0.052200 | 0.001500 | 236.9 | 2.4 |
11 | 168 | 65 | 8 | 0.40 | 26.371310 | 0.271224 | 0.054700 | 0.002800 | 236.1 | 3.1 |
12 | 276 | 60 | 8 | 0.22 | 25.634450 | 0.197138 | 0.052700 | 0.002000 | 244.5 | 2.1 |
13 | 197 | 76 | 12 | 0.38 | 23.148150 | 0.492970 | 0.060600 | 0.001300 | 267.8 | 5.7 |
14 | 488 | 104 | 12 | 0.21 | 25.246150 | 0.216705 | 0.053200 | 0.001700 | 248.6 | 2.2 |
15 | 305 | 158 | 19 | 0.51 | 25.634450 | 0.210280 | 0.055500 | 0.001500 | 244.1 | 1.9 |
16 | 323 | 103 | 13 | 0.32 | 25.258900 | 0.421088 | 0.052300 | 0.001800 | 248.2 | 4.2 |
17 | 233 | 80 | 11 | 0.35 | 25.581990 | 0.242142 | 0.053800 | 0.001900 | 245.4 | 2.7 |
18 | 636 | 696 | 177 | 1.13 | 17.793590 | 0.379934 | 0.072900 | 0.004000 | 343.6 | 6.3 |
19 | 349 | 188 | 48 | 0.51 | 20.755500 | 0.392020 | 0.055060 | 0.000690 | 301.2 | 5.8 |
20 | 201 | 54 | 9 | 0.27 | 24.503800 | 0.300218 | 0.050400 | 0.002500 | 257.1 | 3.5 |
21 | 229 | 69 | 9 | 0.31 | 24.721880 | 0.415597 | 0.050600 | 0.001600 | 254.6 | 3.9 |
22 | 311 | 154 | 35 | 0.48 | 20.618560 | 0.552662 | 0.058600 | 0.002300 | 300.7 | 8.5 |
23 | 283 | 59 | 7 | 0.21 | 25.799790 | 0.226314 | 0.051400 | 0.001400 | 244.1 | 2.2 |
24 | 162 | 84 | 11 | 0.52 | 24.461840 | 0.365013 | 0.053200 | 0.002000 | 256.0 | 3.7 |
25 | 438 | 121 | 13 | 0.28 | 26.191720 | 0.315563 | 0.052200 | 0.001100 | 240.1 | 2.9 |
26 | 398 | 307 | 82 | 0.77 | 20.374900 | 0.319655 | 0.067800 | 0.001600 | 303.0 | 4.8 |
27 | 366 | 203 | 36 | 0.55 | 25.406500 | 0.342110 | 0.054700 | 0.001500 | 245.4 | 3.0 |
28 | 337 | 108 | 24 | 0.32 | 20.820320 | 0.177729 | 0.057700 | 0.001700 | 297.9 | 2.9 |
29 | 342 | 79 | 9 | 0.22 | 24.863250 | 0.185454 | 0.052270 | 0.000790 | 252.6 | 1.8 |
30 | 303 | 128 | 15 | 0.41 | 25.947070 | 0.309695 | 0.055800 | 0.001400 | 241.1 | 3.0 |
31 | 343 | 126 | 23 | 0.36 | 22.794620 | 0.233818 | 0.061200 | 0.002300 | 271.0 | 2.3 |
32 | 575 | 285 | 54 | 0.51 | 23.629490 | 0.256842 | 0.058600 | 0.001900 | 263.1 | 3.0 |
33 | 713 | 675 | 172 | 0.95 | 17.304030 | 0.254515 | 0.060800 | 0.001300 | 358.3 | 5.4 |
34 | 409 | 123 | 17 | 0.30 | 24.061600 | 0.237374 | 0.054900 | 0.001700 | 260.5 | 3.1 |
35 | 284 | 90 | 14 | 0.31 | 25.627880 | 0.229876 | 0.058200 | 0.001500 | 242.7 | 2.3 |
36 | 292 | 362 | 111 | 1.22 | 17.921150 | 0.321168 | 0.061200 | 0.001300 | 346.0 | 6.3 |
37 | 444 | 345 | 91 | 0.77 | 20.416500 | 0.337635 | 0.058700 | 0.001500 | 305.7 | 5.4 |
38 | 478 | 652 | 109 | 1.33 | 20.833330 | 0.998264 | 0.072700 | 0.003600 | 292.0 | 13.0 |
39 | 166 | 53 | 10 | 0.31 | 29.163020 | 0.263649 | 0.060600 | 0.002300 | 213.3 | 1.8 |
40 | 240 | 66 | 8 | 0.28 | 26.874500 | 0.180560 | 0.053800 | 0.001400 | 233.7 | 1.4 |
Spots | SiO2 | HfO2 | UO2 | Al2O3 | Ce2O3 | ThO2 | La2O3 | PbO | TiO2 | ZrO2 | Y2O3 | Total |
---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 32.5 | 1.8 | <0.1 | <0.1 | 0.3 | <0.1 | <0.1 | <0.1 | <0.1 | 63.7 | <0.1 | 98.6 |
2 | 32.6 | 1.7 | <0.1 | 0.2 | 0.2 | <0.1 | <0.1 | <0.1 | <0.1 | 64.4 | <0.1 | 99.3 |
3 | 33.1 | 1.8 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.0 | <0.1 | 100.1 |
4 | 32.6 | 1.7 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 66.4 | <0.1 | 100.9 |
5 | 32.3 | 1.6 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 64.3 | <0.1 | 98.4 |
6 | 32.5 | 1.9 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 66.2 | <0.1 | 100.9 |
7 | 32.4 | 1.8 | <0.1 | <0.1 | 0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.6 | <0.1 | 100.0 |
8 | 32.6 | 1.6 | <0.1 | <0.1 | <0.1 | 0.1 | <0.1 | <0.1 | <0.1 | 65.5 | <0.1 | 99.8 |
9 | 32.7 | 1.6 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.5 | <0.1 | 99.9 |
10 | 32.5 | 1.6 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.6 | <0.1 | 99.9 |
11 | 32.6 | 1.8 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.5 | <0.1 | 100.2 |
12 | 32.8 | 1.9 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | <0.1 | 65.0 | <0.1 | 99.8 |
Elements | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
---|---|---|---|---|---|---|---|
P | 167 | 155 | 149 | 113 | 117 | 74.6 | 81.1 |
Y | 651 | 577 | 766 | 581 | 885 | 718 | 697 |
Nb | 118 | 105 | 152 | 122 | 112 | 109 | 107 |
La | 11.8 | 10.3 | 16.3 | 11.1 | 15.4 | 14.3 | 20.5 |
Ce | 51.2 | 45.3 | 109.4 | 31.7 | 75.2 | 55.9 | 71.1 |
Pr | 2.6 | 2.1 | 4.2 | 2.3 | 3.3 | 3.4 | 4.1 |
Nd | 9.4 | 8.2 | 17.9 | 8.6 | 17.0 | 11.8 | 11.9 |
Sm | 2.6 | 2.1 | 5.3 | 1.9 | 4.1 | 3.5 | 2.3 |
Eu | 0.2 | 0.2 | 0.4 | 0.2 | 0.3 | 0.3 | 0.2 |
Gd | 7.4 | 6.1 | 11.9 | 5.9 | 12.5 | 9.6 | 7.3 |
Tb | 2.9 | 2.4 | 4.2 | 2.2 | 4.1 | 3.2 | 2.6 |
Dy | 42.7 | 35.1 | 57.2 | 34.7 | 57.1 | 44.7 | 39.7 |
Ho | 16.7 | 14.7 | 20.4 | 14.5 | 22.4 | 18.1 | 15.9 |
Er | 93.4 | 85.0 | 110.9 | 85.0 | 117.9 | 98.2 | 93.3 |
Tm | 27.1 | 25.1 | 31.6 | 24.2 | 33.0 | 28.0 | 27.5 |
Yb | 316 | 282 | 351 | 287 | 367 | 316 | 315 |
Lu | 62.7 | 55.9 | 67.9 | 55.1 | 72.7 | 63.4 | 64.2 |
Hf | 8406 | 7785 | 10086 | 7228 | 11441 | 9380 | 11780 |
Ta | 116 | 102 | 134 | 107 | 116 | 109 | 140 |
Pb | 4.6 | 2.8 | 6.1 | 2.8 | 6.7 | 4.8 | 4.0 |
Th | 149 | 114 | 190 | 121 | 184 | 170 | 157 |
U | 180 | 154 | 203 | 161 | 194 | 154 | 165 |
Ce/Ce* | 2.24 | 2.33 | 3.21 | 1.53 | 2.56 | 1.95 | 1.87 |
Eu/Eu* | 0.15 | 0.14 | 0.14 | 0.17 | 0.14 | 0.16 | 0.17 |
(Sm/La)N | 0.35 | 0.32 | 0.52 | 0.27 | 0.43 | 0.40 | 0.18 |
LREE | 85 | 74 | 165 | 62 | 128 | 99 | 118 |
HREE | 562 | 500 | 643 | 502 | 674 | 572 | 558 |
TREE | 647 | 574 | 808 | 564 | 802 | 671 | 676 |
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No, S.-G.; Park, M.-E. The Geochronology and Geochemistry of Zircon as Evidence for the Reconcentration of REE in the Triassic Period in the Chungju Area, South Korea. Minerals 2020, 10, 49. https://doi.org/10.3390/min10010049
No S-G, Park M-E. The Geochronology and Geochemistry of Zircon as Evidence for the Reconcentration of REE in the Triassic Period in the Chungju Area, South Korea. Minerals. 2020; 10(1):49. https://doi.org/10.3390/min10010049
Chicago/Turabian StyleNo, Sang-Gun, and Maeng-Eon Park. 2020. "The Geochronology and Geochemistry of Zircon as Evidence for the Reconcentration of REE in the Triassic Period in the Chungju Area, South Korea" Minerals 10, no. 1: 49. https://doi.org/10.3390/min10010049
APA StyleNo, S.-G., & Park, M.-E. (2020). The Geochronology and Geochemistry of Zircon as Evidence for the Reconcentration of REE in the Triassic Period in the Chungju Area, South Korea. Minerals, 10(1), 49. https://doi.org/10.3390/min10010049