中沙海域的广角与多道地震探测

doi:10.6038/cjg2020N0259

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摘要由于浅滩和暗礁广布，中沙海域（环礁区）长期以来处在南海地震探测的空白区域.为了揭示该区域的地壳结构及地层-构造特征，进而全面刻画南海陆缘新生代伸展过程，我们首次在中沙及其邻近海域完成了1条广角地震测线OBS2017-2和4条多道地震测线的数据采集.对得到的海底地震仪（OBS）数据进行了格式转换、位置校正等初步处理，识别了来自地壳深部的震相并对中沙环礁地壳结构进行了正演模拟；对穿过中沙环礁的多道地震剖面进行了地层-构造解释，共划分出6套地层.OBS2017-2测线处理结果显示，其数据质量良好，深部震相清晰，且位于环礁内的台站震相延伸较长，可达100 km以上.中沙环礁地壳性质为轻微减薄的坚硬大陆块体，厚度约为25 km左右.多道地震剖面显示，环礁之上沉积层厚度较薄，除环礁西南部存在一条基底断裂——"排洪-美溪断裂"外，基本不存在其他构造-岩浆活动.而在环礁坡脚周缘，有广泛的岩浆侵入和喷出体的存在.中沙环礁上较薄的上地壳厚度和沉积特征指示了该区域可能在古新世时期经历的强烈暴露剥蚀作用.中沙海域最新开展的广角和多道地震探测填补了南海地质地球物理研究的空白，为解读该区的构造-沉积演化提供了数据基础.

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	黎雨晗
	黄海波
	丘学林
	杜峰
	龙根元
	张浩宇
	陈瀚
	王强

关键词 ：南海, 中沙海域, 广角地震探测, 多道地震探测, 海底地震仪, 环礁, 沉积地层

Abstract：Due to the wide-spread shoals and reefs, Zhongsha waters (atoll) has long been a blank area for seismic exploration in the South China Sea. To reveal the crustal structures and the stratigraphic-tectonic characteristics of this area, and to comprehensively depict the Cenozoic extension process of the continental margins in the South China Sea, we carried out one wide-angle seismic profile OBS2017-2 and four multi-channel seismic profiles in the Zhongsha Atoll and its adjacent areas for the first time. The Ocean Bottom Seismometer (OBS) data was processed by format conversion, position relocation, etc. The seismic phases from deep crust were identified and used to simulate the crustal structures by forward modeling approach. Six sets of sedimentary strata were established based on the stratigraphic and tectonic interpretation of the multi-channel seismic profiles. The data processing of the OBS2017-2 shows that the data quality is very high, the deep seismic phases are clear and extend longer on the atoll, reaching over 100 km. The Zhongsha Atoll is characterized by slightly-thinned continental crust, with thickness of about 25 km. Sedimentary layers in the atoll are relatively thin as shown in the multi-channel seismic data. Basically, there is few tectonic-magmatic activities exist within the atoll except for a basement-cutting fault that named Paihong-Meixi Fault in the southwest of the atoll. Extensive magmatic intrusions and volcanoes exist only around the slope toe of the Zhongsha Atoll. The thinned upper crust and the sedimentary characteristics in the Zhongsha Atoll indicate that this area may have experienced strong processes of exposure and denudation. The recent wide-angle and multi-channel seismic surveys in the Zhongsha waters have filled in the blank of geological/geophysical research in the South China Sea, providing important data for understanding the tectonic-sedimentary evolution in this area.

Key words： South China Sea Zhongsha Waters Wide-angle seismic survey Multi-channel seismic survey Ocean Bottom Seismometer Atoll Sedimentary strata

收稿日期: 2019-06-13

PACS:

P736

基金资助:国家自然科学基金项目（41676045，41674092，41306046），海南省自然科学基金项目（418QN306）联合资助.

通讯作者: 黄海波,男,1987年生,副研究员,研究方向为深部地球物理.E-mail:go223@scsio.ac.cn E-mail: go223@scsio.ac.cn

作者简介: 黎雨晗,男,1994年生,博士研究生,主要从事海洋地球物理与海底构造研究.E-mail:liyuhan15@mails.ucas.ac.cn

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http://www.geophy.cn//CN/10.6038/cjg2020N0259 或 http://www.geophy.cn//CN/Y2020/V63/I4/1523

Ao W, Zhao M H, Qiu X L, et al. 2010. The correction of shot and OBS position in the 3D seismic experiment of the SW Indian Ocean Ridge. Chinese Journal of Geophysics (in Chinese), 53(12):2982-2991, doi:10.3969/j.issn.0001-5733.2010.12.022.
Chen M, Fang J, Cui R H. 2018. Lithospheric structure of the South China Sea and adjacent regions:Results from potential field modelling. Tectonophysics, 726, 62-72, doi:10.1016/j.tecto.2018.01.021.
Du F. 2018. Three-dimensional OBS relocation and velocity structures of the Manila Subduction Zone in the Northeastern South China Sea[Master's Thesis] (in Chinese). Guangzhou:South China Sea Institute of Oceanology, Chinese Academy of Sciences.
Gozzard S, Kusznir N, Franke D, et al. 2019. South China Sea crustal thickness and oceanic lithosphere distribution from satellite gravity inversion. Petroleum Geoscience, 25(1):112-128, doi:10.1144/petgeo2016-162.
Huang H B, Qiu X L, Pichot T, et al. 2019. Seismic structure of the northwestern margin of the South China Sea:implication for asymmetric continental extension. Geophysical Journal International, 218(2):1246-1261, doi:10.1093/gji/ggz219.
Huang H B, Qiu X L, Xu Y, et al. 2011. Crustal structure beneath the Xisha Islands of the South China Sea simulated by the teleseismic receiver function method. Chinese Journal of Geophysics (in Chinese), 54(11):2788-2798, doi:10.3969/j.issn.0001-5733.2011.11.009.
Jin X L. 1989. The geosciences research report in South China Sea. Donghai Mar. Sci. (in Chinese), 7(4):30-42.
Li C F, Song T R. 2012. Magnetic recording of the Cenozoic oceanic crustal accretion and evolution of the South China Sea Basin. Chinese Science Bulletin, 57(24):3165-3181.
Oshida A, Kubota R, Nishiyama E, et al. 2008. A new method for determining OBS positions for crustal structure studies, using airgun shots and precise bathymetric data. Exploration Geophysics, 39(1):15-25.
Qiu X L, Ye S Y, Wu S M, et al. 2001. Crustal structure across the Xisha Trough, northwestern South China Sea. Tectonophysics, 341(1-4):179-193, doi:10.1016/S0040-1951(01)00222-0.
Qiu X L, Zeng G P, Xu Y, et al. 2006. The crustal structure beneath the Shidao Station on Xisha Islands of South China Sea. Chinese Journal of Geophysics (in Chinese), 49(6):1720-1729.
Qiu X L, Zhao M H, Ao W, et al. 2011. OBS survey and crustal structure of the Southwest Sub-basin and Nansha Block, South China Sea. Chinese Journal of Geophysics (in Chinese), 54(12):3117-3128, doi:10.3969/j.issn.0001-5733.2011.12.012.
Ruan A G, Niu X W, Qiu X L, et al. 2011. A wide angle ocean bottom seismometer profile across Liyue Bank, the southern margin of South China Sea. Chinese Journal of Geophysics (in Chinese), 54(12):3139-3149, doi:10.3969/j.issn.0001-5733.2011.12.014.
Shao L, Li Q Y, Zhu W L, et al. 2017. Neogene carbonate platform development in the NW South China Sea:Litho-, bio-and chemo-stratigraphic evidence. Marine Geology, 385:233-243, doi:10.1016/j.margeo.2017.01.009.
Wang T K, Chen M K, Lee C S, et al. 2006. Seismic imaging of the transitional crust across the northeastern margin of the South China Sea. Tectonophysics, 412(3-4):237-254, doi:10.1016/j.tecto.2005.10.039.
Wang Y L, Yan P, Zheng H B, et al. 2007. Timing and positioning corrections of ocean bottom seismograph data. Journal of Tropical Oceanography (in Chinese), 26(5):40-46.
Wei X, Deng J F, Xie W Y, et al. 2005. Constraints on biogenetic reef formation during evolution of the South China Sea and exploration potential analysis. Earth Science Frontiers (in Chinese), 12(3):245-252.
William C T, Joseph E T. 1991. SAC-Seismic Analysis Code Users Manual. Livermore, CA:Lawrence Livermore National Laboratory, 1-153.
Wu S G, Yang Z, Wang D W, et al. 2014. Architecture, development and geological control of the Xisha carbonate platforms, Northwestern South China Sea. Marine Geology, 350:71-83, doi:10.1016/j.margeo.2013.12.016.
Wu S G, Zhu W L, Ma Y S. 2019. Vicissitude of Cenozoic carbonate platforms in the South China Sea:Sedimentation in semi-closed marginal seas. Marine Geology & Quaternary Geology (in Chinese), 38(6):1-17, doi:10.16562/j.cnki.0256-1492.2018.06.001.
Wu Z C, Gao J Y, Ding W W, et al. 2017. Moho depth of the South China Sea Basin from three-dimensional gravity inversion with constraint points. Chinese Journal of Geophysics (in Chinese), 60(7):2599-2613, doi:10.6038/cjg20170709.
Wu Z L, Li J B, Ruan A G, et al. 2012. Crustal structure of the northwestern sub-basin, South China Sea:Results from a wide-angle seismic experiment. Science China Earth Sciences, 55(1):159-172, doi:10.1007/s11430-011-4324-9.
Xia S H, Qiu X L, Zhao M H, et al. 2008. Investigation on deep crustal structure along the onshore-offshore seismic profile near Hongkong. Progress in Geophysics (in Chinese), 23(5):1389-1397.
Yan P, Zhou D, Liu Z S. 2001. A crustal structure profile across the northern continental margin of the South China Sea. Tectonophysics, 338(1):1-21, doi:10.1016/S0040-1951(01)00062-2.
Yan Q S, Shi X F, Wang K S, et al. 2008. Major element, trace element, and Sr, Nd and Pb isotope studies of Cenozoic basalts from the South China Sea. Science in China Series D:Earth Sciences, 51(4):550-566, doi:10.1007/s11430-008-0026-3.
Yi L, Jian Z M, Liu X Y, et al. 2018. Astronomical tuning and magnetostratigraphy of Neogene biogenic reefs in Xisha Islands, South China Sea. Science Bulletin, 63(9):564-573, doi:10.1016/j.scib.2018.04.001.
Zhang H Y, Qiu X L, Zhang J Z, et al. 2019. Time record and accurate correction of Chinese OBS raw data. Chinese Journal of Geophysics (in Chinese), 62(1):172-182, doi:10.6038/cjg2019L0715.
Zhang L, Zhao M H, Wang J, et al. 2013. Correction of OBS position and recent advances of 3D seismic exploration in the central sub-basin of South China Sea. Earth Science-Journal of China University of Geosciences (in Chinese), 38(1):33-42, doi:10.3799/dqkx.2013.004.
Zhang J Z, Qiu X L, Zhao M H, et al. 2018. Abnormal data retrieval of three-dimensional OBS survey at the Bashi Channel Area of the South China Sea. Chinese Journal of Geophysics (in Chinese), 61(4):1529-1538, doi:10.6038/cjg2018L0268.
Zhang Q, Wu S G, Dong D D. 2016. Cenozoic magmatism in the northern continental margin of the South China Sea:Evidence from seismic profiles. Marine Geophysical Research, 37(2):71-94, doi:10.1007/s11001-016-9266-3.
Zhao M H, Qiu X L, Xia K Y, et al. 2004. Onshore-offshore seismic data processing and preliminary results in the South China Sea. Journal of Tropical Oceanography (in Chinese), 23(1):58-63.
Zhu W L, Xie X N, Wang Z F, et al. 2017. New insights on the origin of the basement of the Xisha Uplift, South China Sea. Science China Earth Sciences, 60(12):2214-2222, doi:10.1007/s11430-017-9089-9.
附中文参考文献
敖威,赵明辉,丘学林等. 2010. 西南印度洋中脊三维地震探测中炮点与海底地震仪的位置校正. 地球物理学报,53(12):2982-2991, doi:10.3969/j.issn.0001-5733.2010.12.022.
杜峰. 2018. 南海东北部马尼拉海沟俯冲带三维OBS位置校正与速度结构特征[硕士论文]. 广州:中国科学院南海海洋研究所.
黄海波,丘学林,胥颐等. 2011. 利用远震接收函数方法研究南海西沙群岛下方地壳结构. 地球物理学报,54 (11):2788-2798, doi:10.3969/j.issn.0001-5733.2011.11.009.
金翔龙. 1989. 南海地球科学研究报告. 东海海洋,7(4):1-92.
丘学林, 曾钢平, 胥颐等. 2006. 南海西沙石岛地震台下的地壳结构研究. 地球物理学报,49(6):1720-1729.
丘学林,赵明辉,敖威等. 2011. 南海西南次海盆与南沙地块的OBS探测和地壳结构. 地球物理学报,54(12):3117-3128, doi:10.3969/j.issn.0001-5733.2011.12.012.
阮爱国,牛雄伟,丘学林等. 2011. 穿越南沙礼乐滩的海底地震仪广角地震试验. 地球物理学报,54(12):3139-3149, doi:10.3969/j.issn.0001-5733.2011.12.014.
王彦林,阎贫,郑红波等. 2007. OBS记录的时间和定位误差校正. 热带海洋学报,26(5):40-16.
魏喜,邓晋福,谢文彦等. 2005. 南海盆地演化对生物礁的控制及礁油气藏勘探潜力分析. 地学前缘,12(3):245-252.
吴时国,朱伟林,马永生. 2019. 南海半封闭边缘海碳酸盐台地兴衰史. 海洋地质与第四纪地质,38(6):1-17, doi:10.16562/j.cnki.0256-1492.2018.06.001.
吴招才,高金耀,丁巍伟等. 2017. 南海海盆三维重力约束反演莫霍面深度及其特征. 地球物理学报, 60(7):2599-2613, doi:10.6038/cjg20170709.
夏少红,丘学林,赵明辉等. 2008. 香港地区海陆地震联测及深部地壳结构研究. 地球物理学进展,23(5):1389-1397.
张浩宇,丘学林,张佳政等. 2019. 国产海底地震仪的时间记录与原始数据精细校正. 地球物理学报, 62(1):172-182, doi:10.6038/cjg2019L0715.
张莉,赵明辉,王建等. 2013. 南海中央次海盆OBS位置校正及三维地震探测新进展. 地球科学——中国地质大学学报,38(1):33-42, doi:10.3799/dqkx.2013.004.
张佳政,丘学林,赵明辉等. 2018. 南海巴士海峡三维OBS探测的异常数据恢复. 地球物理学报,61(4):1529-1538, doi:10.6038/cjg2018L0268.
赵明辉,丘学林,夏戡原等. 2004. 南海东北部海陆联测地震数据处理及初步结果. 热带海洋学报,23(1):58-63.