The 2.65 Ga A-type granite in the northeastern Yangtze craton: Petrogenesis and geological implications
The 2.65 Ga A-type granite in the northeastern Yangtze craton: Petrogenesis and geological implications
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扬子克拉通东北部2.65 Ga A型花岗岩的岩石成因及地质意义
DOI：
10.1016/j.precamres.2015.01.003
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发表时间：
2015-03
影响因子：
3.8
通讯作者：
Saihong Yang
中科院分区：
文献类型：
--
作者：
Jianping Zheng;Zhengwei Qin;Hao Wang;Saihong Yang
克拉通中古老的残留陆壳岩石的存在对于研究它们的早期演化是至关重要的。由于太古宙岩石暴露较差，扬子克拉通早期演化尚未得到很好的制约。本文对扬子克拉通北部胡集镇某花岗岩岩体进行了锆石U-Pb、Hf-O同位素、全岩主量元素、微量元素和Nd同位素的联合研究。岩浆锆石U-Pb定年的加权平均年龄为2656 Ma±5.6 Ma，揭示了除孔岭地体外扬子克拉通另一个太古宙露头。花岗岩样品具有相对较好的(K2O+Na2O)/CaO、TFeO/MgO比值和Zr、Nb、Ce、Ga、Y含量，与A型花岗岩具有相同的特征。在原始地幔归一化微量元素蜘蛛图上有明显的Eu、Sr、Ba负异常，表明岩浆源区残留有斜长石。锆石ɛHf(T)为负的−值为2.7~0.1，Hf模式年龄约为3.2Ga。锆石的δ~(18)O值在4.94~5.72‰之间，平均为5.26±0.14‰，表明表壳岩石对寄主岩浆没有贡献。因此，Hf模式年龄表明，虎集花岗岩是由约3.2Ga年轻地壳岩石改造而形成的。结合前人的研究，新太古代虎集花岗岩的发现表明扬子克拉通中广泛存在太古宙基底。大约2.65Ga Huji花岗岩的产出可能记录了岩石圈的热稳定，从而预示着扬子地块东部克拉通的稳定。
The presence of old residual continental crustal rocks in cratons is crucial for investigation of their early evolution. Due to the poor exposure of Archean rocks, the early evolution of the Yangtze Craton has not been well constrained yet. In this study, a combined study of zircon U–Pb and Hf–O isotopes, as well as whole rock major and trace elements and Nd isotopes have been conducted for a granite pluton at Huji town, in the northern part of the Yangtze Craton. U–Pb dating for magmatic zircons yielded a weighted mean age of 2656 ± 6 Ma, revealing another Archean outcrop in the Yangtze Craton besides the Kongling terrane. The granite samples show relatively evaluated (K2O + Na2O)/CaO, TFeO/MgO ratios, and Zr, Nb, Ce, Ga and Y contents, sharing the same features as the A-type granite. They have pronounced Eu, Sr and Ba negative anomalies on the primitive mantle-normalized trace element spidergram, implying the residual of plagioclase in the magma sources. Their high Zr contents of 440–529 ppm correspond to initial magma temperatures of 930–962 °C. The zircons have negativeɛHf(t) values of −2.7 to 0.1, and Hf model ages of ca. 3.2 Ga, respectively. Theδ18O values of the zircons range between 4.94 and 5.72‰ and give an average of 5.26 ± 0.14‰, suggesting no contribution of supracrustal rock into the host magma. Therefore, the Hf model ages indicate the generation of the Huji granite by reworking of ca. 3.2 Ga juvenile crustal rocks. Combined with previous studies, the finding of the Neoarchean Huji granites with ca. 3.2 Ga Hf model ages suggests the widespread of Archean basement in the Yangtze Craton. The occurrence of the ca. 2.65 Ga Huji granites likely records the thermally stable lithosphere and thus heralds the craton stabilization of the eastern part of the Yangtze Block.
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DOI：
10.1016/0024-4937(92)90029-x
发表时间：
1992-07
期刊：
--
影响因子：
--
作者：
S. Turner;J. Foden;R. S. Morrison
通讯作者：
S. Turner;J. Foden;R. S. Morrison
影响因子：
3.8
作者：
Kang Chen;Shan Gao;Y. Wu;Jing‐Liang Guo;Zhaochu Hu;Yongsheng Liu;K. Zong;Zhengwei Liang;
通讯作者：
Kang Chen;Shan Gao;Y. Wu;Jing‐Liang Guo;Zhaochu Hu;Yongsheng Liu;K. Zong;Zhengwei Liang;
影响因子：
3.8
作者：
J. Moyen;H. Martin;M. Jayananda;B. Auvray
通讯作者：
J. Moyen;H. Martin;M. Jayananda;B. Auvray
DOI：
10.1080/10020070612330050
发表时间：
2006-10
期刊：
Progress in Natural Science
影响因子：
--
作者：
L. Xiaoming;G. Shan;Ling Wenli;Yu Honglin;Hu Zhao-chu
通讯作者：
L. Xiaoming;G. Shan;Ling Wenli;Yu Honglin;Hu Zhao-chu
影响因子：
3.4
作者：
M. Sandiford;S. McLaren;N. Neumann
通讯作者：
M. Sandiford;S. McLaren;N. Neumann