First Direct Evidence of Pan-African Orogeny Associated with Gondwana Assembly in the Cathaysia Block of Southern China.
First Direct Evidence of Pan-African Orogeny Associated with Gondwana Assembly in the Cathaysia Block of Southern China.
复制标题
华南华夏地块泛非造山运动与冈瓦纳大陆组装有关的首个直接证据
DOI：
10.1038/s41598-017-00950-x
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发表时间：
2017-04-11
影响因子：
4.6
通讯作者：
He J
中科院分区：
文献类型：
--
作者：
Li L;Lin S;Xing G;Jiang Y;He J
华南地块角闪石岩中变质锆石U-Pb年龄为533 ± 7 Ma，Hf模式年龄为900 ~ 1200 Ma。地球化学和同位素特征表明，角闪石岩的原始岩浆可能来自富集的软流圈地幔源区。这一新元古代晚期-寒武纪（泛非洲）变质事件提供了第一个直接证据，表明SCB是冈瓦纳组合的一个组成部分。结合已有的地质资料表明，SCB与印度或澳大利亚有很大的亲缘关系，泛非变质事件最有可能属于东库恩加造山带。我们认为，SCB位于印度，南极和澳大利亚之间的连接沿着东冈瓦纳大陆的北方边缘，与华夏地块连接澳大利亚西部，而扬子地块面对印度北方约。公元533年。
Metamorphic zircon from a hornblendite in the South China Block (SCB) yield U-Pb age of 533 ± 7 Ma and Hf model ages from 900 to 1200 Ma. Geochemical and isotopic characteristics indicate that primary magma of the hornblendites was probably derived from an enriched asthenospheric mantle source. This Late Neoproterozoic–Cambrian (Pan-African) metamorphic event provides the first direct evidence that the SCB was an integral part of the Gondwana assembly. Combined with available geological data which show that the SCB has great affinity with India or Australia, the Pan-African metamorphic event most likely belongs to the eastern Kuunga orogeny. We propose that the SCB was located at the nexus between India, Antarctica and Australia along the northern margin of East Gondwana, with the Cathaysia Block connecting western Australia whereas the Yangtze Block facing northern India at ca. 533 Ma.