Zircon SHRIMP U-Pb dating of the Neogene coral reefs,Xisha Islands,South China Sea:implications for tectonic evolution

• 作者: Da-peng Su Hai-yang Zhang Hong Xu Long-wei Qiu Meng Tao Na Qin Shan-ying Li Shou-jie Liu Shu-shen Lu Tong-qiang Shi Wei-wei Zhang Yan-qiou Yang Zhao-peng Ji
• 来源期刊: 中国地质（英文）
• 年，卷（期）: 2018,（1）
• 所属期刊栏目: Original Articles
• 页码范围: 49-60
• 页数: 12页
• 语种: 中文
• DOI: 10.31035/cg2018007

摘要

The Xisha Block is a minor one in the South China Sea and an important tectonic unit in the northwestern part of the region. Zircon SHRIMP U-Pb ages for three volcanic intrusive core samples from Xike-1,an exploratory well penetrating the bioherms of the Xisha Islands. The core samples are from the Miocene reef carbonate bedrock and are recognized as dark-gray biotite-hornblende gabbro,gray fine-grained bi-otite diorite,and gray fine-grained granite,respectively. Zircon cathodoluminescence (CL) images and trace Th,U and Pb compositions of the zircons show that these rocks are of volcanic intrusive origin. Zir-con SHRIMP U-Pb dating yielded six groups of ages,ranging from 2451-1857 Ma to early Cretaceous,which indicate that the formation and evolution of the Xisha Block was affected by the evolution and clos-ure of Neotethys Ocean,probably within its eastern extension into South China Sea. Both old,deep-sourced material,including fragments from Rodina supercontinent,and recent mantle-derived magma products contributed to the emergence and formation of the Xisha block. The SHRIMP U-Pb results also proved that this process differed from that of the Kontum massif,the Hainan Block,and the South China Block,but is similar to that of the Nansha and Zhongsha blocks. The process was associated with the ef-fects of Yanshanian magmatism induced by subduction mechanisms of the Paleo-Pacific Plate or the re-working of the multiple magmatisms since the Early to mid-Yanshanian,possibly jointly experienced by the Xisha-Zhongsha-Nansha Block.

作者信息

序号	姓名	单位	发文数	被引次数	H指数	G指数
1	Hong Xu		1	0	0.0	0.0
2	Zhao-peng Ji		1	0	0.0	0.0
3	Shan-ying Li		1	0	0.0	0.0
4	Yan-qiou Yang		1	0	0.0	0.0
5	Shou-jie Liu		2	0	0.0	0.0
6	Hai-yang Zhang		1	0	0.0	0.0
7	Shu-shen Lu		1	0	0.0	0.0
8	Tong-qiang Shi		1	0	0.0	0.0
9	Meng Tao		1	0	0.0	0.0
10	Na Qin		1	0	0.0	0.0
11	Wei-wei Zhang		1	0	0.0	0.0
12	Da-peng Su		1	0	0.0	0.0
13	Long-wei Qiu		1	0	0.0	0.0