地震研究

提高对马尼拉俯冲带海啸生成机制的认识对研究我国东南沿海地区海洋防灾减灾具有重要意义。目前,大型俯冲带震源破裂的运动过程对海啸生成的影响逐渐受到关注,但震源运动学破裂过程对马尼拉俯冲带潜在海啸的影响尚未明确。基于马尼拉俯冲带的典型破裂模型,对不同破裂速度和方向设定的海啸情景开展数值模拟,评估分析破裂速度和方向对海啸波传播特征的影响。结果表明:破裂方向相同时,破裂速度越慢,海啸波到时越晚,峰值波高越小; 破裂速度相同时,与不考虑破裂运动过程的模拟结果相比,破裂前方的场点峰值波高更大,距离初始破裂位置更近的场点到时越早; 不同设定情境下,沿海场点的海啸波到时最大相差10 min左右,峰值波高最大值约为最小值的1.5倍。

Enhancing the understanding of the tsunami generation mechanism in the Manila subduction zone is of great significance to marine disaster prevention and reduction in the southeastern coastal areas of China.So far,scientistshave shown great concern about the impact of the kinematic source rupture process in the large-scale subduction zone on the tsunami generation.However,the impact of the earthquake source kinematic rupture process in the Manila subduction zone has not been investigated clearly yet.Based on the typical scenario of rupture model of the Manila subduction zone,this study conducts numerical simulations of tsunami scenarios with different rupture velocities and directions separately.It aims to evaluate and analyze the influence of rupture velocity and rupture direction on the propagation characteristics of the tsunami wave.The results show that when the rupture direction keeps the same,the slower the rupture velocity,the later the tsunami wave arrives and the smaller the peak wave height.When the rupture velocity keeps the same,the peak wave height at the sites in front of the rupture is much higher,and the wave at sites closer to the initial rupture location will arrive earlier,compared with the simulation results that do not consider the rupture kinematic process.Among the different scenarios,the arrival time of tsunami waves at the coastal sites may differ 10 minutes at most,and the maximum peak-wave value is about 1.5 times as large as the minimum peak-wave value.

引言
1 基于震源破裂运动学的海啸数值模拟
2 马尼拉俯冲带海啸情景的设定
3 破裂速度的影响
4 破裂方向性的影响
5 结论

图1 33个子断层位置、尺寸、滑移量以及6个虚拟验潮站位置<br/>Fig.1 The location,size,slip of 33 sub-faults and the locations of 6 virtual tide gauges

图1 33个子断层位置、尺寸、滑移量以及6个虚拟验潮站位置
Fig.1 The location,size,slip of 33 sub-faults and the locations of 6 virtual tide gauges

表1 设定海啸情景的破裂方向以及破裂速度的控制参数VS<br/>Tab.1 The rupture direction and the rupture velocity control parameter VS of tsunami scenarios

表1 设定海啸情景的破裂方向以及破裂速度的控制参数VS
Tab.1 The rupture direction and the rupture velocity control parameter VS of tsunami scenarios

图2 设定破裂速度分别为1 km/s(a)、2 km/s(b)、3 km/s(c)和4 km/s(d)时各子断层的起始破裂时间<br/>Fig.2 Initial rupture time of each sub-fault when the rupture velocity is 1 km/s(a),2 km/s(b),3 km/s(c)and 4 km/s(d)

图2 设定破裂速度分别为1 km/s(a)、2 km/s(b)、3 km/s(c)和4 km/s(d)时各子断层的起始破裂时间
Fig.2 Initial rupture time of each sub-fault when the rupture velocity is 1 km/s(a),2 km/s(b),3 km/s(c)and 4 km/s(d)

图3 设定4种破裂速度考虑震源运动学破裂过程模拟的海啸波在1号验潮站的波形比较<br/>Fig.3 Comparison of simulated tsunami waveform at No.1 tide gauge considering four scenarios with different rupture velocities in kinematic rupture process

图3 设定4种破裂速度考虑震源运动学破裂过程模拟的海啸波在1号验潮站的波形比较
Fig.3 Comparison of simulated tsunami waveform at No.1 tide gauge considering four scenarios with different rupture velocities in kinematic rupture process

图4 4种海啸情景下6个验潮站记录的海啸波时程<br/>Fig.4 Simulated tsunami waveform at 6 tide gauges considering four scenarios

图4 4种海啸情景下6个验潮站记录的海啸波时程
Fig.4 Simulated tsunami waveform at 6 tide gauges considering four scenarios

图5 设定3种破裂起始点分别为最北端(a)、中间(b)和最南端(c)时各子断层的起始破裂时间<br/>Fig.5 Initial rupture time of each sub-fault when their initial points are at the northernmost end(a),central part(b)and southernmost end(c)

图5 设定3种破裂起始点分别为最北端(a)、中间(b)和最南端(c)时各子断层的起始破裂时间
Fig.5 Initial rupture time of each sub-fault when their initial points are at the northernmost end(a),central part(b)and southernmost end(c)

图6 设定3种破裂起始点考虑震源运动学破裂过程模拟的海啸波在1号验潮站的波形比较<br/>Fig.6 Comparison of simulated tsunami waveform at No.1 tide gauge considering three scenarios with different rupture initial locations in kinematic rupture process

图6 设定3种破裂起始点考虑震源运动学破裂过程模拟的海啸波在1号验潮站的波形比较
Fig.6 Comparison of simulated tsunami waveform at No.1 tide gauge considering three scenarios with different rupture initial locations in kinematic rupture process

图7 3种海啸情景下6个验潮站记录的海啸波时程<br/>Fig.7 Simulated tsunami waveforms recorded at 6 tide gauges considering three scenarios

图7 3种海啸情景下6个验潮站记录的海啸波时程
Fig.7 Simulated tsunami waveforms recorded at 6 tide gauges considering three scenarios

图8 瞬时破裂情景下最大海啸波高空间分布<br/>Fig.8 Spatial distribution of the maximum tsunami wave height in the instantaneous-rupture scenario

图8 瞬时破裂情景下最大海啸波高空间分布
Fig.8 Spatial distribution of the maximum tsunami wave height in the instantaneous-rupture scenario

图9 考虑震源运动学破裂过程海啸情景与瞬时破裂情景的最大海啸波高差值空间分布图(绿色五角星代表破裂起始位置)<br/>Fig.9 The spatial distribution of the maximum tsunami wave height difference between the tsunami scenarios with source kinematic rupture process and instantaneous rupture

图9 考虑震源运动学破裂过程海啸情景与瞬时破裂情景的最大海啸波高差值空间分布图(绿色五角星代表破裂起始位置)
Fig.9 The spatial distribution of the maximum tsunami wave height difference between the tsunami scenarios with source kinematic rupture process and instantaneous rupture

李宏伟,徐志国,史健宇,等.2024.基于俯冲带动力学参数评估琉球海沟对我国东南沿岸的海啸威胁[J].地球科学,49(2):403-413.
Li H W,Xu Z G,Shi J Y,et al.2024.Tsunami potential threat from the Ryukyu Trench on Chinese coast based on subduction zone dynamics parameters[J].Earth Science,49(2):403-413.(in Chinese)
李琳琳,邱强,李志刚,等.2022.南海海啸灾害研究进展及展望[J].中国科学:地球科学,52(5):803-831.
Li L L,Qiu Q,Li Z G,et al.2022.Tsunami hazard assessment in the South China Sea:A review of recent progress and research gaps[J].Scientia Sinica Terrae,65(5):783-809.(in Chinese)
刘也.2018.中国东南沿海海啸危险性区域特征分析[D].哈尔滨:中国地震局工程力学研究所.
Liu Y.2018.Regional characteristics of the probabilistic tsunami hazard for the southeast coastal area of China[D].Harbin:Institute of Engineering Mechanics,China Earthquake Administration.(in Chinese)
刘哲,任鲁川.2024.耦合震级、震源深度和滑动角不确定性效应的地震海啸危险性估计[J].地震研究,47(2):233-244.
Liu Z,Ren L C.2024.Estimation of the risk of earthquake-induced tsunami by coupling uncertainty of magnitude,focal depth and slip angle[J].Journal of Seismological Researh,47(2):233-244.(in Chinese)
王培涛,于福江,赵联大,等.2012.越洋海啸的数值模拟及其对我国的影响分析[J].海洋学报,34(2):39-47.
Wang P T,Yu F J,Zhao L D,et al.2012.Numerical simulation of trans-oceanie tsunami and its impact analysis on Chinese coasts[J].Acta Oceanologica Sinica,34(2):39-47.(in Chinese)
王晓青,吕金霞,丁香.2006.我国地震海啸危险性初步探讨[J].华南地震,26(1):76-80.
Wang X Q,Lu J X,Ding X.2006.A preliminary study on the risk of tsunami in China[J].South China Journal of Seismology,26(1):76-80.(in Chinese)
温瑞智,任叶飞,李小军.2011.日本MW9.0级地震海啸数值模拟与启示[J].国际地震动态,1(4):22-27.
Wen R Z,Ren Y F,Li X J.2011.The tsunami simulation for off the Pacific coast of Tohoku earthquake and disaster mitigation in China[J].Recent Developments in World Seismology,1(4):22-27.(in Chinese)
温瑞智,任叶飞,周正华等.2008.越洋海啸的数值模拟[J].地震工程与工程振动,28(4):28-34.
Wen R Z,Ren Y F,Zhou Z H,et al.2008.Preliminary study on numerical simulation of transoceanic tsunami[J].Journal of Earthquake Engineeringand Engineering Dynamics,28(4):28-34.(in Chinese)
杨智博.2015.中国地震海啸危险性分析[D].哈尔滨:中国地震局工程力学研究所.
Yang Z B.2015.Probabilistic tsunami hazard analysis aloneg Chinese coast[D].Harbin:Institute of Engineering Mechanics,China Earthquake Administration.(in Chinese)
张鹏.2017.中国东南沿海海啸危险性分析[D].哈尔滨:中国地震局工程力学研究所.
Zhang P.2017.Probabilistic tsunami hazard analysis along Chinese coast[D].Harbin:Institute of Engineering Mechanics,China Earthquake Administration.(in Chinese)
郑旭,周少辉.2022.马尼拉海沟俯冲带板缘地震特征及衰减关系研究[J].华南地震,42(1):86-96.
Zheng X,Zhou S H.2022.Study on the characteristics and attenuation relationship of plate margin earthquakes in the subduction zone of Manila Trench[J].South China Journal of Seismology,42(1):86-96.(in Chinese)
Ben-Menahem A,Rosenman M.1972.Amplitude patterns of tsunami waves from submarine earthquakes[J].Journalof Geophysical Research,77(17):3097-3128.
Fujii Y,Satake K.2007.Tsunami source of the 2004 Sumatra-Andaman earthquake inferred from tide gauge and satellite data[J].Bulletin of the Seismological Society of America,97(1A):S192-S207.
Geist E L.1998.Local tsunamis and earthquake source parameters[M]//Advances in Geophysics.Elsevier,39:117-209.
Graves R W,Pitarka A.2010.Broadband ground-motion simulation using a hybrid approach[J].Bulletin of the Seismological Society of America,100(5A):2095-2123.
Grilli S T,Ioualalen M,Asavanant J,et al.2007.Source constraints and model simulation of the December 26,2004,Indian Ocean tsunami[J].Journal of Waterway,Port,Coastal,and Ocean Engineering,133(6):414-428.
Liu P L F,Wang X,Salisbury A J.2009.Tsunami hazard and early warning system in South China Sea[J].Journal of Asian Earth Sciences,36(1):2-12.
Liu Y,Santos A,Wang S M,et al.2007.Tsunami hazards along Chinese coast from potential earthquakes in South China Sea[J].Physics of the Earth and Planetary Interiors,163(1-4):233-244.
Megawati K,Shaw F,Sieh K,et al.2009.Tsunami hazard from the subduction megathrust of the South China Sea:Part I.Source characterization and the resulting tsunami[J].Journal of Asian Earth Sciences,36(1):13-20.
Okada Y.1992.Internal deformation due to shear and tensile faults in a half-space[J].Bulletin of the Seismological Society of America,82(2):1018-1040.
Okal E A,Reymond D,Hébert H.2013.From earthquake size to far-field tsunami amplitude:development of a simple formula and application to DART buoy data[J].Geophysical Journal International,196(1):340-356.
Okal E A.1988.Seismic parameters controlling far-field tsunami amplitudes:A review[J].Natural Hazards,1(1):67-96.
Ren Y,Wen R,Song Y.2014.Recent progress of tsunami hazard mitigation in China[J].Episodes Journal of International Geoscience,37(4):277-283.
Ren Y,Wen R,Zhang P,et al.2017.Implications of local sources to probabilistic tsunami hazard analysis in south Chinese coastal area[J].Journal of Earthquake and Tsunami,11(1):1740001.
Ren Z,Liu H,Zhao X,et al.2019.Effect of kinematic fault rupture process on tsunami propagation[J].Ocean Engineering,181(3-4):43-58.
Satake K,Fujii Y,Harada T,et al.2013.Time and space distribution of coseismic slip of the 2011 Tohoku earthquake as inferred from tsunami waveform data[J].Bulletin of the Seismological Society of America,103(2B):1473-1492.
Suppasri A,Imamura F,Koshimura S.2010.Effects of the rupture velocity of fault motion,ocean current and initial sea level on the transoceanic propagation of tsunami[J].Coastal Engineering Journal,52(2):107-132.
Wang P,Lu W,Wang Y,et al.2024.Multi-scale free oscillations and resonances over the continental shelf of the East China Sea from the 2011 Tohoku-Oki tsunami[J].Ocean Modelling,188(2):1-16.
Williamson A,Melgar D,Rim D.2019.The effect of earthquake kinematics on tsunami propagation[J].Journal of Geophysical Research:Solid Earth,124(11):11639-11650.

备注

引言

1 基于震源破裂运动学的海啸数值模拟

2 马尼拉俯冲带海啸情景的设定

3 破裂速度的影响

4 破裂方向性的影响

5 结论

期刊信息