Tracing a late Mesozoic magmatic arc along the Southeast Asian margin from the granitoids drilled from the northern South China Sea
Tracing a late Mesozoic magmatic arc along the Southeast Asian margin from the granitoids drilled from the northern South China Sea
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从南海北部钻探的花岗岩中追踪东南亚边缘的晚中生代岩浆弧
DOI：
10.1080/00206814.2015.1056256
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发表时间：
2016-01
影响因子：
2.6
通讯作者：
许长海
中科院分区：
文献类型：
--
作者：
许长海
摘要南海北方钻探发现的花岗岩类岩套对了解晚中生代东南亚大陆边缘的演化具有重要意义。它们包括一系列岩石类型，包括闪长岩、英云闪长岩、花岗闪长岩、二长花岗岩和正长花岗岩，SiO2含量为56.4- 76.8%。新获得的14个钻孔样品的二次离子质谱（西姆斯）U-Pb年龄显示了两个关键的岩浆期：晚侏罗世（161.6- 148.2Ma）和早白垩世（136.5- 101.7Ma）。侏罗纪岩浆活动可能开始于中侏罗世晚期，由继承锆石的年代记录。花岗岩类主要由变铝质到弱过铝质的I型花岗岩组成，介于镁铁质和铁质之间，包括钙碱性、高钾钙碱性和钾玄质系列。地球化学特征表明，这些花岗岩类主要形成于正常的陆弧环境。I型样品的显著特征是明确的Nb-Ta-Ti负异常，这是典型的弧相关岩浆。南海晚中生代岛弧花岗岩、东南部巴拉望海脊的增生楔以及南海北部贯穿中国东南部的岩石圈伸展带共同构成了晚中生代东南亚大陆边缘的一个东南-西北向的沟-弧-弧后结构，其地球动力学背景与古太平洋板块向亚洲大陆俯冲有关。两个关键的俯冲幕，一个在晚侏罗世和早白垩世的时间被确认。
Abstract The granitoid suites encountered by drilling in the northern South China Sea (SCS) remain important for understanding the evolution of the late Mesozoic Southeast Asian continental margin. They comprise a range of rock types including diorite, tonalite, granodiorite, monzogranite and syenogranite with SiO2 spanning 56.4–76.8%. Newly acquired secondary ion mass spectrometry (SIMS) U–Pb ages of samples from 14 boreholes indicate two key magmatic episodes: Late Jurassic (161.6–148.2 Ma) and Early Cretaceous (136.5–101.7 Ma). Jurassic magmatism probably began in late Middle Jurassic time, documented by the dates of inherited zircons. The granitoids are dominated by metaluminous to weakly peraluminous I-type granites, are transitional between magnesian and ferroan, and encompass calc-alkaline, high-K calc-alkaline, and shoshonitic series. The geochemical signatures suggest that these granitoids were mostly generated in a normal continental arc environment. Notable features of the I-type samples are well-defined negative Nb–Ta–Ti anomalies typical of arc-related magmas. Taken together, the late Mesozoic arc granites of the SCS, the accretionary wedge of the Palawan terrane to the southeast, and the zone of lithospheric extension north of the SCS throughout Southeast China, define a southeast-to-northwest trench-arc-backarc architecture for the late Mesozoic Southeast Asian continental margin whose geodynamic setting is related to subduction of the Palaeo-Pacific slab beneath the Asian continent. Two key subduction episodes are recognized, one in Late Jurassic and the other in Early Cretaceous time.
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影响因子：
3.9
作者：
Zhenyu He;Xi‐sheng Xu
通讯作者：
Zhenyu He;Xi‐sheng Xu
DOI：
10.1144/gsl.sp.1984.016.01.05
发表时间：
1984
期刊：
Geological Society, London, Special Publications
影响因子：
--
作者：
A. Saunders;J. Tarney
通讯作者：
A. Saunders;J. Tarney
DOI：
--
发表时间：
2008
期刊：
Acta Geological Sinica
影响因子：
--
作者：
X. Guang-fu
通讯作者：
X. Guang-fu
影响因子：
2.7
作者：
D. Davis;R. J. Sewell;S. Campbell
通讯作者：
D. Davis;R. J. Sewell;S. Campbell
二叠纪以来华南大陆边缘岩浆的开启与关闭：安第斯型板块边界向西太平洋型板块边界的转变
影响因子：
2.9
作者：
Li, Zheng-Xiang;Li, Xian-Hua;Chung, Sun-Lin;Lo, Ching-Hua;Xu, Xisheng;Li, Wu-Xian
通讯作者：
Li, Wu-Xian