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热带海洋学报 >

2016 , Vol. 35 >Issue 1: 61 - 71

DOI: https://doi.org/10.11978/2015025

海洋地球物理学

南沙地块海底地震仪转换横波震相识别最新进展*

  • 张莉 ,
  • 赵明辉 ,
  • 丘学林 ,
  • 王强
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  • 1. 中国科学院边缘海地质重点实验室, 中国科学院南海海洋研究所, 广东 广州 510301;
    2. 中国科学院大学, 北京 100049
张莉(1989—), 女, 四川省广安市人, 硕士研究生, 主要从事海洋地球物理研究。E-mail: zephy@foxmail.com

收稿日期: 2015-02-12

  网络出版日期: 2016-02-02

基金资助

国家自然科学基金(41276049、91428204、91028002、41176053)

收起

Recent progress of converted shear-wave phase identification in Nansha Block using Ocean Bottom Seismometers data

  • ZHANG Li ,
  • ZHAO Minghui ,
  • QIU Xuelin ,
  • WANG Qiang
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  • 1. Key Laboratory of Marginal Sea Geology of Chinese Academy of Sciences, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China;
    2. University of Chinese Academy of Sciences, Beijing 100049, China

Received date: 2015-02-12

  Online published: 2016-02-02

Supported by

Natural Science Foundation of China (41276049, 91428204, 91028002)

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摘要

通过挖掘海底地震仪记录的转换横波信息, 可以促进对地壳岩性、均质性的认识。以南海南沙地块OBS973-1剖面上18个台站的数据为实例, 阐明了海底地震仪横波震相识别的方法。首先对三分量OBS (Ocean Bottom Seismometer )地震数据进行带通滤波、维纳滤波、极化滤波等去噪处理, 然后利用能量扫描法求得极化角进行水平分量坐标旋转, 求取最佳径向分量。数据处理结果表明, 相对于OBS记录的磁罗盘方位角, 能量扫描法求取的极化角更为准确可靠。最后通过OBS973-1地震剖面垂直分量与径向分量上的纵横波走时对比、质点运动轨迹、速度模型试算等手段, 进一步确定了转换横波震相的类别。在南沙地块OBS探测中成功地在10个台站中识别出了PgSs、PnSc、Pms等震相, 不仅可以为下一步横波速度结构模拟提供坚实的数据基础, 而且可以为今后OBS转换横波在其他地区的有效应用与推广提供借鉴。

关键词： 海底地震仪(OBS); 转换横波; 滤波; 水平分量旋转; 南沙地块

本文引用格式

张莉 , 赵明辉 , 丘学林 , 王强 . 南沙地块海底地震仪转换横波震相识别最新进展*[J]. 热带海洋学报, 2016 , 35(1) : 61 -71 . DOI: 10.11978/2015025

Abstract

Using converted shear-wave information recorded by Ocean Bottom Seismometer (OBS) can promote our understanding about lithology and physical properties of crustal rocks. Taking 18 OBS stations along Profile OBS973-1 of Nansha Block in the South China Sea (SCS) as examples, we illustrated the method of OBS converted shear-wave identification. First, noise reduction processing of three-component OBS seismic data was completed using a band-pass filter, Wiener filter and polarization filter. Then, we used energy scanning method to find out the polarization angle, and obtained the optimal radial component data by horizontal component rotation. The results showed that the angle obtained by energy scanning method was more accurate and reliable than the magnetic compass angle recorded by OBS. Finally, the types of converted shear-waves were determined through the comparisons of travel times, particle trajectory and velocity model trial between vertical component and radial component. The method was applied successfully to the experiment in Nansha Block of the SCS for Profile OBS973-1. A few converted shear-wave phase groups, such as PgSs, PnSc and PmS, were identified in 10 OBSs. These results not only provided solid foundation for shear-wave velocity structure, but also offered experience and reference for effective application and promotion of OBS-converted shear-wave in other areas in the future.

Key words： Ocean Bottom Seismometer (OBS); converted shear wave; filter; horizontal components rotation; Nansha Block

参考文献

1 李春峰, 周祖翼, 李家彪, 等, 2007. 台湾岛南部海域的前碰撞构造地球物理特征[J]. 中国科学 D辑(地球科学), 37(5): 649-659. LI C F, ZHOU Z Y, LI J B, et al, 2007. Precollisional tectonics and terrain amalgamation offshore southern Taiwan: Charac- terizations from reflection seismic and potential field data[J]. Science in China Series D: Earth Sciences, 37(5), 649-659.
2 李家彪, 金翔龙, 阮爱国, 等, 2004. 马尼拉海沟增生楔中段的挤入构造[J]. 科学通报, 49(10): 1000-1008. LI J B, JIN X L, RUAN A G, et al, 2004. Indentation tectonics in the accretionary wedge of middle Manila Trench [J]. Chinese Science Bulletin, 49(10): 1000-1008.
3 丘学林, 赵明辉, 徐辉龙, 等, 2012. 南海深地震探测的重要科学进程: 回顾和展望[J]. 热带海洋学报, 31(3): 1-8. QIU X L, ZHAO M H, XU H L, et al, 2012. Important processes of deep seismic surveys in the South China Sea: Retrospection and expectation [J]. Journal of Tropical Oceanography, 31(3): 1-8.
4 孙金龙, 徐辉龙, 曹敬贺, 2011. 台湾—吕宋会聚带的地壳运动特征及其动力学机制[J]. 地球物理学报, 54(12): 3016-3025. SUN J L, XU H L, CAO J H, 2012. Crustal movement and its dynamic mechanism of the Taiwan-Luzon convergent zone [J]. Chinese J. Geophys, 54(12): 3016-3025.
5 田丽艳, 2003. 马里亚纳海槽热液活动区玄武岩岩石地球化学研究[D]. 青岛: 中国海洋大学: 1-72. TIAN L Y, 2003. The study of petrological geochemistry of basalts from hyrothermal fields, Mariana Trough[D]. Qingdao: Ocean University of China: 1-72.
6 赵明辉, 丘学林, 夏少红, 等, 2008. 大容量气枪震源及其波形特征[J]. 地球物理学报, 51(2): 558-565. ZHAO M H, QIU X L, XIA S H, et al, 2008. Large volume air~gun sources and its seismic waveform characters[J]. Chinese J Geophys, 51(2): 558-565.
7 ARCULUS R, ISHIZUKA O, BOGUS K A, 2013. Izu-Bonin- Mariana arc origins: continental crust formation at intraoceanic arc: foundations, inceptions, and early evolution [R/OL]. IODP Sci Prosp, 351. [2015-04-16] doi:10.2204/ iodp.sp.351.2013. http://publications.iodp.org/scientific_prospectus/351/
8 BIRD P, 2003. An updated digital model of plate boundaries [J/OL]. Geochem Geophys Geosyst, 4(3): 1-52. [2015-04-16]. http://dx.doi.org/ 10.1029/2001GC000252.
9 BLOOMER S H, STERN R J, FISK E, et al, 1989. Shoshonitic volcanism in the northern Mariana arc 1. Mineralogic and major and trace element characteristics[J]. J Geophys Res, 94(B4): 4469-4496.
10 CALVERT A J, KLEMPERER S L, TAKAHASHI N, et al, 2008. Three-dimensional crustal structure of the Mariana island arc from seismic tomography[J]. J Geophys Res, 113(B1): 1-24. doi:10.1029/2007JB004939.
11 CALVERT A J, 2011. The seismic structure of island arc crust[M] // BROWN D, RYAN P D. Arc-continent collision. Berlin: Springer Berlin Heidelberg: 87-119.
12 CHRISTENSEN N I, MOONEY W D, 1995. Seismic velocity structure and composition of the continental crust: A global view [J]. J Geophys Res, 100(B6): 9761-9788. doi:10.1029/ 95JB00259.
13 EAKIN D H, MCINTOSH K D, VAN AVENDONK H J A, et al, 2014. Crustal‐scale seismic profiles across the Manila subduction zone: The transition from intraoceanic subduction to incipient collision[J]. Journal of Geophysical Research: Solid Earth, 119(1): 1-17.
14 FACCENDA M, GERYA T V, MANCKTELOW, N S, et al, 2012. Fluid flow during slab unbending and dehydration: implications for intermediate-depth seismicity, slab weakening and deep water recycling[J]. Geochem Geophys Geosyst, 13(1): 1-23.
15 FACCENDA M, 2014. Water in the slab: A trilogy[J]. Tectonophysics, 614: 1-30.
16 GVIRTZMAN Z, STERN R J, 2004. Bathymetry of Mariana trench-arc system and formation of the Challenger Deep as a consequence of weak plate coupling [J]. Tectonics, 23(2), 1-15. doi:10.1029/2003TC001581
17 KEY K, 2012. Marine electromagnetic studies of seafloor resources and tectonics [J]. Surveys in Geophysics, 33(1): 135-167. doi:10.1007/s10712-011-9139-x.
18 KEY K, CONSTABLE S, LIU L, et al, 2013. Electrical image of passive mantle upwelling beneath the northern East Pacific Rise [J]. Nature, 495(7442): 499-502.
19 KODAIRA S, SATO T, TAKAHASHI N, et al, 2007a. New seismological constraints on growth of continental crust in the Izu-Bonin intra-oceanic arc[J]. Geology, 35(11): 1031-1034. doi:10.1130/G23901A.
20 KODAIRA S, SATO T, TAKAHASHI N, et al, 2007b. Seismological evidence for variable growth of crust along the Izu intraoceanic arc[J]. J Geophys Res, 112: 1-25. doi:10.1029/2006JB004593.
21 LESTER R, MCINTOSH K, AVENDONK H V, et al, 2013. Crustal accretion in the Manila trench accretionary wedge at the transition from subduction to mountain-building in Taiwan [J]. Earth Planet Sci Lett, 375: 430-440.
22 MATSUNO T, SEAMA N, EVANS R L, et al, 2010. Upper mantle electrical resistivity structure beneath the central Mariana subduction system [J]. Geochemistry, Geophysics, Geosystems, 11(9): 5424-5425.
23 NAIF S, KEY K, CONSTABLE S, et al, 2013. Melt-rich channel observed at the lithosphere-asthenosphere boundary [J]. Nature, 495(7441): 356-359.
24 PEARCE J A, REAGAN M K, STERN R J, et al, 2013. Izu-Bonin-Mariana fore arc: testing subduction initiation and ophiolite models by drilling the outer Izu-Bonin-Mariana fore arc [R/OL]. IODP Sci Prosp, 352. [2015-04-16]. doi:10. 14379/iodp.sp.352.2013. http://publications.iodp.org/scientific_ prospectus/352/
25 RUDNICK R L, FOUNTAIN D M, 1995. Nature and composition of the continental crust: a lower crustal perspective [J]. Reviews of geophysics, 33(3): 267-309.
26 STERN R J, 2002. Subduction zones [J]. Reviews of Geophysics, 40(4): 1012. doi:10.1029/2001RG000108.
27 SUYEHIRO K, TAKAHASHI N, ARIIE Y, et al, 1996. Continental crust, crustal underplating and low-Q upper mantle beneath an oceanic island arc [J]. Science, 272: 390-392. doi:10.1126/ science.272.5260.390.
28 TAKAHASHI N, KODAIRA S, TATSUMI Y, et al, 2008. Structure and growth of the Izu-Bonin-Mariana arc crust: 1. Seismic constraint on crust and mantle structure of the Mariana arc-back-arc system [J]. J Geophys Res, 113: B01104. doi:10. 1029/2007JB005120.
29 TAKAHASHI N, KODAIRA S, TATSUMI Y, et al, 2009. Structural variations of arc crusts and rifted margins in the southern Izu-Ogasawara arc-back arc system [J]. Geochem Geophys Geosyst, 10(9): 1-28.
30 TAMURA Y, BUSBY C, BLUM P, 2013. Izu-Bonin-Mariana Rear Arc: The missing half of the subduction factory [R/OL]. IODP Sci Prosp, 350. [2015-04-16]. doi:10.2204/iodp.sp.350.2013. http://publications.iodp.org/scientific_prospectus/350/
31 TATSUMI Y, SHUKUNO H, TANI K, et al, 2008. Structure and growth of the Izu-Bonin-Mariana arc crust: 2. Role of crust-mantle transformation and the transparent Moho in arc crust evolution [J]. J Geophys Res, 113(B02203): 1-19. doi:10.1029/2007JB005121.
32 TIBI R, WIENS D A, SHIOBARA H, et al, 2006. Depth of the 660-km discontinuity near the Mariana slab from an array of ocean bottom seismographs[J]. Geophysical Research Letters, 33(2): 1-4. doi:10.1029/ 2005GL024523.
33 TOH H, BABA K, ICHIKI M, et al, 2006. Two-dimensional electrical section beneath the eastern margin of Japan Sea [J]. Geophys Res Lett, 33(22): L22309.
34 WESSEL P, SMITH W H F, 1995. New version of the Generic Mapping Tools released, EOS Trans[J]. AGU, 76: 329.
35 WORZEWSKI T, JEGEN M, KOPP H, et al, 2010. Magnetotelluric image of the fluid cycle in the Costa Rican subduction zone [J]. Nature Geoscience, 4(2): 108-111.
36 YU H S, 2000. Closure of Manila Trench north of Latitude 21°N in transition of passive-convergent margin south of Taiwan[J]. Acta Oceanographica Taiwanica, 38(2): 115-127.
37 YUASA M, NOHARA M, 1992. Petrographic and geochemical along-arc variations of volcanic rocks on the volcanic front of the Izu-Ogasawara (Bonin) Arc[J]. Geological Survey of Japan Bulletin, 43: 421-456.
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