Chronological, geochemical characteristics and tectonic evolution significance of the Sanyan eclogites in the Jinsha River suture zone, eastern Xizang
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摘要:
金沙江−哀牢山缝合带作为东特提斯构造域的关键组成部分，被广泛认为是一条古特提斯造山带。然而，由于缺乏标志性高压/超高压岩石的变质作用研究，该区域洋壳俯冲闭合过程及后续碰撞造山演化一直未能得到有效约束。研究针对藏东金沙江缝合带“三岩地区”新发现的榴辉岩，开展了系统的野外调查、岩相学观察、锆石U-Pb测年及全岩主微量元素分析。根据退变质程度、主要矿物组合及结构特征，将“三岩地区”榴辉岩划分为石榴钠长阳起片岩、石榴阳起石岩、榴闪岩和榴辉岩4类。选取2件榴辉岩样品进行锆石U-Pb测年，获得206Pb/238U年龄分别为 247±2 Ma 和 246±1 Ma。锆石具有低 Th/U 比值、极低的Nb、Ta 和重稀土元素（HREE）含量，且无明显 Eu 负异常，表明其为榴辉岩相变质成因，~246 Ma 代表榴辉岩相变质时代。12 件样品的全岩主量元素分析显示原岩为苦橄质玄武岩−玄武岩，微量元素特征揭示原岩构造背景多样，包括洋岛玄武岩（OIB）、正常型洋中脊玄武岩（N-MORB）和富集型洋中脊玄武岩（E-MORB），表明“三岩地区”榴辉岩主要由古特提斯洋壳物质（洋岛及洋中脊玄武岩）经俯冲作用形成，属于洋壳型榴辉岩。结合前期研究获得的榴辉岩锆石U-Pb 年龄和多硅白云母 Ar-Ar 坪年龄，进一步限定金沙江古特提斯洋在中三叠世早期（T21）完全闭合。
Abstract:Objective As a key component of the eastern Tethys tectonic domain, the Jinsha River–Ailao Mountain suture zone is widely recognized as a Paleo-Tethys orogenic belt. However, due to the lack of metamorphic studies on high-pressure/ultra-high-pressure rocks, the subduction-to-closure process of the oceanic crust and the subsequent collisional orogenic evolution remain poorly constrained.
Methods Systematic field surveys, petrographic observations, zircon U–Pb dating, and whole-rock major and trace element analyses were carried out on the newly discovered eclogites in the Sanyan area of the Jinsha River suture zone in eastern Xizang. Based on the degree of retrogressive metamorphism, major mineral assemblages, and textural features, the Sanyan eclogites are classified into four types: garnet–albite–actinolite schist, garnet–actinolite, garnet–amphibolite, and eclogite.
Results Zircon U–Pb dating of two eclogite samples yields 206Pb/238U ages of 247±2 Ma and 246±1 Ma, respectively. These zircons feature low Th/U ratios, extremely low content of Nb, Ta, and HREE, and no obvious negative Eu anomalies. Therefore, the genesis of the zircons should be eclogite-facies metamorphism, with the ~246 Ma age representing the timing of eclogite-facies metamorphism.
Conclusion The whole-rock major element analysis of 12 samples shows that the protoliths are picritic basalt–basalt, and the trace element characteristics reveal diverse tectonic settings of the protoliths, including ocean island basalt (OIB), normal mid-ocean ridge basalt (N-MORB), and enriched mid-ocean ridge basalt (E-MORB), suggesting that the Sanyan eclogites were mainly formed by subduction of Paleo-Tethys oceanic crust materials (ocean islands and mid-ocean ridge basalts).
Significance Combining the previously obtained zircon U–Pb ages of eclogites and the Ar–Ar plateau ages of phengites, the complete closure of the Jinsha River Paleo-Tethys Ocean in the early Middle Triassic (T21) is further constrained.
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Key words:
- Jinsha River suture zone /
- eclogite /
- subduction /
- Paleo-Tethys /
- Qinghai–Xizang Plateau /
- geochemistry
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图 1 青藏高原及东南缘大地构造简图(据Xu et al.，2015修改)
Figure 1.
图 6 榴辉岩样品的球粒陨石标准化REE模式图和原始地幔标准化微量元素蛛网图（球粒陨石、原始地幔数据引自McDonough and Sun，1995）
Figure 6.
图 10 金沙江古特提斯缝合带构造演化模式图（据王立全等，1999修改）
Figure 10.
表 1 榴辉岩样品的主量元素含量和稀土微量含量
Table 1. Major and trace element composition of eclogites
样品号 22SD01-1 22SD01-2 22SD02-1 22SD02-2 22SD02-3 22SD03-1 22SD03-2 D4058-1 D4058-2 D4058-3 岩性 石榴钠长阳起片岩 榴闪岩 石榴阳起石岩 SiO2 /% 47.94 49.59 51.13 50.77 51.25 51.54 52.02 41.88 47.73 47.72 TiO2 /% 0.49 0.47 0.85 1.21 0.50 1.06 0.92 2.09 1.98 1.84 Al2O3 /% 17.95 16.22 11.76 12.06 14.40 11.46 11.45 13.10 13.66 13.56 FeOT/% 5.84 5.94 9.67 10.23 6.99 9.74 9.51 15.98 15.88 16.40 MnO /% 0.06 0.06 0.19 0.20 0.12 0.13 0.12 0.24 0.20 0.20 MgO/% 4.56 5.30 7.17 6.93 6.59 7.50 7.64 5.35 5.23 5.88 CaO /% 16.72 15.88 12.88 12.60 15.20 13.80 13.88 12.04 7.46 6.82 Na2O/% 3.67 4.41 4.89 4.88 4.41 4.70 4.85 3.91 3.70 3.76 K2O/% 0.43 0.29 0.04 0.04 0.02 0.02 0.02 0.10 0.48 0.46 P2O5 /% 0.19 0.32 0.02 0.02 0.03 0.02 0.02 0.31 0.22 0.23 LOI /% 2.01 1.61 0.78 0.64 0.83 <0.01 0.10 5.98 3.48 2.96 Total/% 99.86 100.09 99.38 99.58 100.34 99.96 100.53 100.98 100.02 99.83 Mg# 58 62 57 55 63 58 59 38 37 39 Na2O+K2O/% 4.10 4.70 4.93 4.92 4.43 4.72 4.87 4.01 4.18 4.22 Na2O/K2O 8.5 15.2 111.1 116.2 191.7 313.3 269.4 39.1 7.7 8.2 Li/ (×10−6) 46.90 52.90 64.90 73.20 66.30 39.30 40.60 12.70 27.60 13.20 Be/(×10−6) 5.67 5.56 7.57 6.86 6.10 3.74 5.90 1.32 0.57 0.96 Sc/(×10−6) 5.67 5.56 7.57 6.86 6.10 3.74 5.90 1.32 0.57 0.96 V/(×10−6) 93.90 83.30 102.00 104.00 101.00 180.00 177.00 396.00 401.00 383.00 Cr/(×10−6) 72.60 67.20 114.00 142.00 126.00 168.00 163.00 163.00 215.00 156.00 Co/(×10−6) 9.83 13.70 19.10 18.00 13.80 23.90 24.80 35.80 44.90 36.20 Ni/(×10−6) 30.20 33.80 58.00 65.60 63.60 57.60 60.60 43.80 61.50 48.80 Cu/(×10−6) 13.20 8.14 20.90 7.39 8.14 10.90 11.30 20.60 75.40 21.70 Zn/(×10−6) 125.00 146.00 155.00 149.00 144.00 126.00 133.00 87.20 103.00 91.80 Ga/(×10−6) 39.10 34.80 19.70 20.00 35.40 22.20 20.60 21.40 23.30 17.80 Rb/(×10−6) 24.30 13.40 1.90 1.86 0.96 0.82 0.73 8.22 32.30 20.80 Sr/(×10−6) 1300.00 1100.00 83.80 75.20 600.00 63.50 57.80 267.00 117.00 77.60 Y/(×10−6) 40.70 32.60 40.30 50.00 37.30 49.90 45.00 43.20 38.70 33.20 Zr/(×10−6) 85.30 73.40 150.00 187.00 88.50 178.00 168.00 119.00 114.00 118.00 Nb/(×10−6) 8.44 7.66 20.20 22.90 8.49 19.00 16.80 24.60 22.10 17.40 Sn/(×10−6) 6.50 5.27 3.49 3.20 5.30 3.56 3.40 1.61 1.46 1.46 Cs/(×10−6) 2.01 0.82 0.08 0.09 0.07 0.10 0.09 5.23 9.73 5.14 Ba/(×10−6) 29.20 12.20 17.80 25.60 8.20 6.10 10.30 83.80 208.00 135.00 La/(×10−6) 44.30 36.20 55.60 68.00 126.00 105.00 86.60 13.50 18.00 14.70 Ce/(×10−6) 78.90 66.80 102.00 124.00 228.00 192.00 157.00 26.90 34.90 28.40 Pr/(×10−6) 9.41 8.02 12.30 14.40 27.00 23.60 19.30 3.74 4.66 4.00 Nd/(×10−6) 34.90 29.40 44.80 53.60 105.00 90.10 74.30 17.10 20.00 16.40 Sm/(×10−6) 6.68 5.82 8.15 9.46 21.30 18.40 14.80 4.45 4.66 4.10 Eu/(×10−6) 1.47 1.34 1.30 1.66 4.19 3.69 2.98 1.45 1.57 1.34 Gd/(×10−6) 5.80 5.44 6.09 7.70 14.50 12.20 9.94 4.36 4.55 4.25 Tb/(×10−6) 1.16 1.01 1.01 1.33 1.91 1.57 1.29 0.97 0.92 0.84 Dy/(×10−6) 6.91 6.04 6.38 8.06 8.32 8.55 7.11 6.89 6.34 5.58 Ho/(×10−6) 1.30 1.10 1.31 1.66 1.25 1.66 1.49 1.43 1.31 1.20 Er/(×10−6) 3.26 2.64 4.00 4.94 3.08 5.09 4.56 4.10 3.70 3.44 Tm/(×10−6) 0.43 0.34 0.63 0.78 0.43 0.78 0.72 0.60 0.57 0.52 Yb/(×10−6) 2.52 1.90 4.42 5.36 2.64 5.35 4.96 3.96 3.84 3.45 Lu/(×10−6) 0.36 0.29 0.76 0.90 0.43 0.91 0.85 0.65 0.62 0.54 Hf/(×10−6) 3.14 2.82 5.45 7.52 3.87 6.94 7.22 5.29 6.30 6.33 Ta/(×10−6) 0.57 0.56 1.20 0.54 0.39 0.70 0.57 1.07 1.00 0.89 Tl/(×10−6) 0.15 0.11 0.01 0.01 0.00 0.00 0.00 0.07 0.22 0.11 Pb/(×10−6) 187.00 150.00 11.80 11.80 76.20 5.54 4.94 3.52 2.34 2.10 Th/(×10−6) 15.80 13.90 22.30 27.20 32.60 36.70 31.60 1.41 2.22 1.96 U/(×10−6) 4.70 4.00 2.58 3.18 6.66 6.48 5.18 0.35 0.36 0.32 ΣREE/(×10−6) 197.40 166.34 248.75 301.85 544.05 468.90 385.90 90.10 105.64 88.76 LREE/HREE 8.08 7.87 9.11 8.82 15.71 11.99 11.48 2.92 3.83 3.48 δEu 0.72 0.73 0.56 0.59 0.73 0.75 0.75 1.01 1.04 0.98 LaN/YbN 12.61 13.67 9.02 9.10 34.23 14.08 12.52 2.45 3.36 3.06 
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表 2 榴辉岩样品的锆石LA-ICP-MS U-Pb年龄
Table 2. LA-ICP-MS U-Pb data of zircons in eclogites
分析点 含量 /（×10−6） Th/U 同位素比值 年龄/Ma Th U 207Pb/206Pb 1σ 207Pb/235U 1σ 206Pb/238U 1σ 207Pb/235U 1σ 206Pb/238U 1σ 21LM01 21LM01-01 7.84 54.3 0.14 0.0474 0.0060 0.2405 0.0243 0.0391 0.0010 219 20 247 6 21LM01-02 6.62 51.5 0.13 0.0632 0.0087 0.3185 0.0340 0.0402 0.0011 281 26 254 7 21LM01-03 11.20 52.9 0.21 0.0542 0.0059 0.2866 0.0267 0.0388 0.0010 256 21 245 6 21LM01-04 4.29 58.9 0.07 0.0627 0.0074 0.3261 0.0251 0.0392 0.0010 287 19 248 6 21LM01-05 8.07 68.6 0.12 0.0446 0.0050 0.2355 0.0210 0.0391 0.0009 215 17 247 5 21LM01-06 7.11 48.4 0.15 0.0502 0.0069 0.2527 0.0281 0.0388 0.0009 229 23 245 6 21LM01-07 6.93 49.3 0.14 0.0683 0.0085 0.3276 0.0299 0.0388 0.0010 288 23 246 6 21LM01-08 7.48 58.7 0.13 0.0484 0.0052 0.2502 0.0221 0.0391 0.0011 227 18 247 7 21LM01-09 7.12 81.2 0.09 0.0450 0.0043 0.2411 0.0182 0.0391 0.0009 219 15 247 6 21LM01-10 3.85 81.4 0.05 0.0484 0.0048 0.2554 0.0233 0.0390 0.0009 231 19 247 6 21LM01-11 5.81 41.1 0.14 0.0412 0.0071 0.2190 0.0353 0.0388 0.0012 201 29 245 7 21LM01-12 6.77 52.4 0.13 0.0491 0.0072 0.2309 0.0215 0.0391 0.0010 211 18 247 6 21LM01-13 5.93 46.9 0.13 0.0442 0.0067 0.2132 0.0232 0.0391 0.0013 196 19 248 8 21LM01-14 6.41 28.0 0.23 0.0622 0.0106 0.2916 0.0321 0.0392 0.0015 260 25 248 10 21LM01-15 5.39 47.9 0.11 0.0613 0.0081 0.3064 0.0273 0.0390 0.0010 271 21 247 6 21LM01-16 8.00 46.4 0.17 0.0570 0.0083 0.2869 0.0318 0.0388 0.0010 256 25 246 7 21LM01-17 4.69 45.7 0.10 0.0530 0.0069 0.2644 0.0267 0.0389 0.0010 238 21 246 6 21LM01-18 6.64 54.3 0.12 0.0455 0.0060 0.2334 0.0214 0.0393 0.0011 213 18 248 7 21LM01-19 4.04 26.8 0.15 0.0506 0.0130 0.2451 0.0596 0.0391 0.0016 223 49 247 10 21LM01-20 4.99 54.2 0.09 0.0517 0.0058 0.2627 0.0203 0.0388 0.0010 237 16 246 6 21LM01-21 7.44 59.2 0.13 0.0484 0.0055 0.2562 0.0243 0.0387 0.0010 232 20 245 6 21LM01-22 6.79 44.4 0.15 0.0508 0.0069 0.2494 0.0319 0.0388 0.0010 226 26 245 6 21LM01-23 7.99 58.7 0.14 0.0529 0.0056 0.2763 0.0225 0.0401 0.0010 248 18 253 6 D4058-1 D4058-1-01 0.95 178 0.01 0.0517 0.0022 0.2786 0.0120 0.0391 0.0006 250 10 247 4 D4058-1-02 10.70 249 0.04 0.0510 0.0020 0.2752 0.0109 0.0390 0.0005 247 9 247 3 D4058-1-03 2.65 463 0.01 0.0508 0.0015 0.2764 0.0088 0.0393 0.0006 248 7 249 3 D4058-1-06 1.84 309 0.01 0.0506 0.0020 0.2715 0.0103 0.0391 0.0005 244 8 247 3 D4058-1-07 2.03 296 0.01 0.0541 0.0019 0.2895 0.0100 0.0390 0.0005 258 8 246 3 D4058-1-09 2.19 238 0.01 0.0536 0.0023 0.2857 0.0116 0.0388 0.0004 255 9 245 3 D4058-1-10 2.22 414 0.01 0.0519 0.0014 0.2797 0.0078 0.0390 0.0004 250 6 247 3 D4058-1-11 1.69 263 0.01 0.0483 0.0021 0.2554 0.0106 0.0386 0.0004 231 9 244 3 D4058-1-12 1.67 311 0.01 0.0532 0.0019 0.2812 0.0094 0.0385 0.0004 252 7 243 2 D4058-1-13 2.91 378 0.01 0.0520 0.0017 0.2806 0.0096 0.0390 0.0004 251 8 246 2 D4058-1-14 1.45 249 0.01 0.0517 0.0022 0.2743 0.0114 0.0387 0.0004 246 9 245 3 D4058-1-15 2.72 439 0.01 0.0520 0.0016 0.2778 0.0088 0.0386 0.0003 249 7 244 2 D4058-1-16 2.73 292 0.01 0.0484 0.0016 0.2583 0.0085 0.0387 0.0004 233 7 245 3 D4058-1-18 4.43 443 0.01 0.0525 0.0018 0.2853 0.0096 0.0393 0.0005 255 8 249 3 D4058-1-19 8.65 259 0.03 0.0546 0.0021 0.2927 0.0111 0.0390 0.0005 261 9 246 3 D4058-1-20 2.04 367 0.01 0.0550 0.0020 0.2952 0.0106 0.0389 0.0004 263 8 246 3 D4058-1-21 1.67 268 0.01 0.0531 0.0020 0.2887 0.0110 0.0394 0.0005 258 9 249 3 D4058-1-22 3.78 315 0.01 0.0512 0.0018 0.2746 0.0100 0.0387 0.0005 246 8 245 3 D4058-1-23 5.57 314 0.02 0.0493 0.0016 0.2653 0.0089 0.0389 0.0005 239 7 246 3 D4058-1-24 1.88 282 0.01 0.0550 0.0019 0.2927 0.0098 0.0387 0.0005 261 8 245 3
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表 3 榴辉岩样品的锆石稀土元素含量（μg/g）
Table 3. REE analytical data in situ single zircon of eclogites
点号 La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu ∑REE *Eu *Ce Nb Ta 21LM01 21LM01-01 bd 0.88 bd 0.151 0.36 0.11 1.16 0.37 3.79 1.23 4.27 0.92 8.31 1.54 23.11 0.53 1.07 0.19 0.04 21LM01-02 bd 0.75 0.023 0.082 0.13 0.04 0.23 0.11 0.74 0.30 1.23 0.22 2.38 0.37 6.61 0.69 0.93 0.16 0.06 21LM01-03 bd 1.31 0.011 0.162 0.86 0.20 1.79 0.42 3.03 0.86 2.67 0.46 4.53 0.73 17.03 0.49 0.85 0.10 0.03 21LM01-04 0.0062 0.51 bd bd 0.32 0.06 0.57 0.087 1.46 0.49 1.78 0.32 2.83 0.48 8.91 0.46 0.69 0.14 0.07 21LM01-05 0.0177 1.44 bd 0.162 0.47 0.26 0.83 0.22 1.98 0.39 1.39 0.22 1.99 0.23 9.61 1.27 9.04 0.11 0.04 21LM01-06 bd 0.86 0.011 0.158 0.30 0.19 1.15 0.38 3.93 1.16 4.50 1.12 8.34 1.52 23.62 0.98 bd 0.13 0.04 21LM01-07 bd 0.78 bd 0.077 0.37 0.08 0.43 0.20 2.10 0.71 2.35 0.51 4.63 0.77 12.99 0.59 bd 0.17 0.04 21LM01-08 bd 0.86 bd 0.080 0.04 0.13 0.54 0.14 1.78 0.56 1.97 0.47 4.60 0.74 11.90 2.73 bd 0.37 0.04 21LM01-09 bd 0.89 0.013 bd 0.24 0.10 0.57 0.13 1.24 0.47 1.89 0.38 2.72 0.40 9.05 0.83 bd 0.21 0.08 21LM01-10 bd 0.87 0.011 0.040 0.34 0.29 1.28 0.38 2.39 0.65 2.01 0.38 2.98 0.51 12.13 1.37 bd 0.16 0.06 21LM01-11 bd 0.62 bd 0.126 0.31 0.12 0.74 0.27 2.27 0.67 2.41 0.50 4.30 0.77 13.09 0.73 bd 0.10 0.04 21LM01-12 0.0057 0.66 0.011 0.117 0.13 0.07 0.87 0.19 1.78 0.53 2.46 0.48 4.27 0.62 12.20 0.63 20.60 0.16 0.03 21LM01-13 bd 0.49 0.011 0.120 0.09 0.09 0.53 0.10 1.63 0.55 2.48 0.43 4.65 0.78 11.94 1.29 bd 0.13 0.02 21LM01-14 0.0059 0.70 bd 0.285 0.22 0.19 1.36 0.39 3.65 1.13 3.77 0.68 6.29 1.02 19.70 1.08 7.90 0.12 0.02 21LM01-15 bd 0.77 0.012 bd 0.09 0.05 0.71 0.07 0.90 0.36 1.01 0.15 1.43 0.28 5.83 0.64 bd 0.13 0.03 21LM01-16 0.0184 0.68 0.024 0.087 0.01 0.13 0.77 0.22 2.05 0.60 2.51 0.50 5.29 0.62 13.49 8.12 8.03 0.12 0.04 21LM01-17 0.0052 0.60 bd 0.035 0.15 0.25 1.15 0.24 1.90 0.43 1.25 0.27 1.96 0.37 8.60 1.80 12.70 0.13 0.02 21LM01-18 bd 0.82 bd 0.084 0.13 0.11 0.63 0.21 1.90 0.54 1.91 0.31 3.48 0.59 10.73 1.21 bd 0.07 0.04 21LM01-19 bd 0.50 0.035 0.042 0.09 0.05 0.34 0.12 1.17 0.33 1.41 0.34 3.06 0.57 8.06 0.90 bd 0.20 0.05 21LM01-20 bd 0.60 0.010 bd 0.16 0.06 0.65 0.16 1.57 0.43 1.47 0.32 2.68 0.46 8.57 0.61 bd 0.14 0.03 21LM01-21 bd 0.67 bd 0.124 0.13 0.09 0.79 0.18 1.62 0.64 2.04 0.42 3.66 0.69 11.06 0.87 bd 0.18 0.03 21LM01-22 bd 0.84 0.010 0.069 0.07 0.03 0.52 0.18 2.12 0.55 2.26 0.42 4.71 0.65 12.44 0.53 bd 0.19 0.04 21LM01-23 0.0253 1.21 0.034 0.160 0.36 0.23 1.51 0.45 2.95 0.69 2.24 0.39 3.39 0.61 14.24 0.96 10.20 0.09 bd D4058-1 D4058-1-01 bd 0.28 bd 0.058 0.72 0.98 8.86 3.44 30.8 7.16 19.19 3.06 23.70 3.77 102.04 1.19 0.93 0.22 0.04 D4058-1-02 0.0159 0.44 0.009 0.131 0.81 1.13 9.64 3.19 27.2 5.82 17.20 3.06 27.72 5.07 101.47 1.24 9.03 0.24 0.06 D4058-1-03 bd 0.61 0.005 bd 0.48 0.42 4.35 1.16 9.2 1.93 5.19 0.80 6.19 1.02 31.33 0.89 0.93 0.33 0.10 D4058-1-06 0.0168 0.36 0.002 0.260 0.87 1.29 9.21 2.82 22.7 4.65 13.46 2.13 17.32 2.90 77.97 1.39 16.93 0.18 0.04 D4058-1-07 bd 0.30 bd 0.099 0.67 0.78 7.61 2.91 25.4 5.56 14.92 2.28 17.56 2.90 80.98 1.05 0.69 0.31 0.08 D4058-1-09 0.0157 0.36 0.013 0.032 0.62 0.92 9.51 3.35 29.2 6.40 18.64 2.94 22.72 3.72 98.45 1.16 6.07 0.27 0.04 D4058-1-10 bd 0.63 bd 0.028 0.28 0.43 3.09 0.88 6.0 1.34 3.85 0.69 5.38 0.77 23.40 1.42 bd 0.25 0.07 D4058-1-11 bd 0.38 0.010 0.031 0.58 0.87 7.46 2.92 25.8 5.35 14.94 2.28 18.11 2.96 81.68 1.28 bd 0.34 0.08 D4058-1-12 bd 0.41 0.015 0.127 0.99 1.09 9.06 2.73 22.7 4.79 14.25 2.36 19.12 3.01 80.62 1.11 bd 0.22 0.40 D4058-1-13 0.0088 0.61 0.005 0.048 1.04 1.29 8.98 2.70 22.1 4.68 12.76 2.14 17.87 2.84 77.12 1.29 22.48 0.18 0.05 D4058-1-14 bd 0.41 0.010 0.109 0.71 0.98 9.13 3.21 29.0 6.35 17.05 2.80 21.76 3.45 94.96 1.18 bd 0.29 0.07 D4058-1-15 bd 0.60 bd 0.127 1.12 1.14 7.29 2.01 13.2 2.84 9.34 1.40 11.91 1.85 52.83 1.22 bd 0.22 0.10 D4058-1-16 0.0370 0.42 0.004 0.054 0.74 1.01 9.48 3.40 27.9 5.99 16.56 2.68 21.15 3.58 93.01 1.16 8.17 0.31 0.05 D4058-1-17 bd 0.63 0.010 0.183 0.84 0.87 7.80 2.46 19.0 4.08 11.63 2.02 15.70 2.56 67.78 1.04 bd 0.2 0.07 D4058-1-19 bd 0.35 0.002 0.115 0.86 0.99 9.62 3.34 30.2 6.77 20.78 3.85 33.91 5.95 116.69 1.06 bd 0.37 0.05 D4058-1-20 bd 0.48 0.005 0.058 0.51 0.50 4.75 1.38 11.1 2.56 6.27 1.07 7.42 1.22 37.30 0.98 bd 0.26 0.10 D4058-1-21 bd 0.40 bd 0.121 0.62 0.87 9.29 3.32 30.1 6.50 17.58 2.97 22.50 3.71 97.96 1.10 bd 0.23 0.07 D4058-1-23 0.0083 0.46 0.015 0.090 0.81 0.95 8.63 3.14 27.7 6.27 17.92 3.15 26.10 4.39 99.67 1.10 9.87 0.29 0.08 D4058-1-24 0.0563 0.75 0.001 0.203 1.35 1.27 10.60 3.43 28.3 6.06 16.88 2.77 21.22 3.46 96.36 1.03 23.23 0.22 0.04 注：*Ce=CeN/(LaN×PrN)1/2；*Eu=EuN/(SmN×GdN)1/2；bd—低于检测限
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