热带海洋学报 ›› 2021, Vol. 40 ›› Issue (3): 25-33.doi: 10.11978/YG2020011

• 综述 • 上一篇    下一篇

南海东部马尼拉俯冲带深部结构新认识*

赵明辉1,2,6(), 程锦辉1,2,6, 高金尉3, 孙龙涛1,2, 徐亚4, 张佳政1,2, 杜峰5   

  1. 1.中国科学院边缘海与大洋地质重点实验室, 中国科学院南海海洋研究所, 广东 广州 511458
    2.南方海洋科学与工程广东省实验室, 广东 广州 511458
    3.中国科学院深海科学与工程研究所, 海南 三亚 572000
    4.中国科学院油气资源研究重点实验室, 中国科学院地质与地球物理研究所, 北京 100029
    5.湖北省地震局, 地震预警湖北省重点实验室, 湖北 武汉 430071
    6.中国科学院大学, 北京 100049
  • 收稿日期:2020-12-29 修回日期:2021-01-20 出版日期:2021-05-10 发布日期:2021-01-20
  • 通讯作者: 赵明辉
  • 作者简介:赵明辉(1967—), 女, 辽宁省锦州市人, 博士生导师, 研究员, 研究方向为海洋地球物理。email: mhzhao@scsio.ac.cn
  • 基金资助:
    国家自然科学基金项目(91958212);国家自然科学基金项目(41730532);国家自然科学基金项目(91428204);国家自然科学基金项目(91858212);南方海洋科学与工程广东省实验室(广州)人才团队引进重大专项(GML2019ZD0204);广东省基金团队项目(2017A030312002)

New development on crustal structures of the Manila subduction in the eastern South China Sea

ZHAO Minghui1,2,6(), CHENG Jinhui1,2,6, GAO Jinwei3, SUN Longtao1,2, XU Ya4, ZHANG Jiazheng1,2, DU Feng5   

  1. 1. Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 511458, China
    2. Guangdong Laboratory of Marine Science and Engineering, Guangzhou 511458, China
    3. Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
    4. Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
    5. Hubei Key Laboratory of Earthquake Early Warning, Hubei Earthquake Agency, Wuhan 430071, China
    6. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2020-12-29 Revised:2021-01-20 Online:2021-05-10 Published:2021-01-20
  • Contact: ZHAO Minghui
  • Supported by:
    Natural Science Foundation of China(91958212);Natural Science Foundation of China(41730532);Natural Science Foundation of China(91428204);Natural Science Foundation of China(91858212);Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)(GML2019ZD0204);Guangdong Natural Science Foundation research team project(2017A030312002)

摘要:

2015—2018年, 国家自然科学基金重大研究计划“南海深海过程演变”的重点支持项目“南海东部马尼拉俯冲带深部结构探测与研究”以马尼拉俯冲带为研究重点, 从深部地球物理的角度探索南海形成演化史与运行规律。项目执行期间, 在国家基金委共享航次协助下, 先后开展和参与5次综合地球物理探测, 共投放海底地震仪(Ocean Bottom Seismometer, OBS)台站73台次, 海底电磁仪(Ocean Bottom ElectroMagnetometers, OBEM)仪器5台次, 累积放炮达13872炮, 成功获得了60台OBS数据和5台OBEM数据。同时, 取得了一系列创新性研究成果: (1)基于人工地震探测及天然地震层析成像结果, 确定南海东北部的地壳属性为受到张裂后期岩浆活动影响的减薄陆壳(12~15km), 划分了南海北部陆缘洋陆边界(Continent-Ocean Boundary, COB); (2)根据多道地震反射剖面, 划分了马尼拉俯冲带北部增生楔前缘的精细结构; (3)圈定了南海停止扩张时洋壳范围; (4)初步构建了南海与菲律宾海板块构造演化模型。本项目为重大研究计划“南海深海过程演变”核心科学问题(海底扩张的年代与过程)提供了实质性的证据, 同时为南海构造演化生命史的“骨架”提供了重要的基础数据, 具有深远的科学意义。

关键词: 马尼拉俯冲带, 深部结构, 海底地震仪, 洋陆边界, 南海东部

Abstract:

The key project of "Deep Structure survey and study on the Manila subduction zone in the eastern South China Sea (SCS)" was funded from the major research program "Deep Sea Processes and Evolution of the SCS" of the National Natural Science Foundation of China (NSFC) during 2015-2018. This project focuses on the Manila subduction zone to resolve the formation and evolution of the SCS using geological and geophysical methods. Five comprehensive geophysical surveys were successively carried out during the project period with the help of NSFC open cruises. A total of 73 Ocean Bottom Seismometer (OBS) stations and five Ocean Bottom ElectroMagnetometers (OBEM) have been deployed; and 13,872 airgun shots were fired. Totally 60 OBSs and five OBEMs have been recovered, and a large amount of data have been acquired. At the same time, a series of innovative results have been obtained. (1) The crust of the northeastern SCS has been determined as a 12-15 km thinned continental crust affected by volcanic activities after post-rifting phase based on the results of active seismic and earthquake tomography; and its continent-ocean boundary (COB) was also determined. (2) According to the multi-channel seismic reflection profile, the detailed structure of the accretionary wedge front of the northern Manila subduction zone was delineated. (3) The SCS oceanic crust domain when the seafloor spreading stopped has been outlined. (4) The tectonic evolution model of the SCS and the Philippine Sea Plate (PSP) was constructed. This project not only contributes substantially to the key scientific question (age and process of seafloor spreading) of the major research program "Deep Sea Processes and Evolution of the SCS," but also provides important basic data for the "skeleton" of the tectonic evolution and life history of the SCS from seafloor spreading to plate subduction, which has a far-reaching scientific significance.

Key words: Manila subduction zone, deep structure, Ocean Bottom Seismometers, Continent-Ocean boundary, eastern South China Sea

中图分类号: 

  • P738