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2011年MW9.0东日本大地震动力学破裂过程的数值模拟

DOI: 10.6038/cjg20150910, PP. 3133-3143

Keywords: 东日本大地震,断层破裂过程,断层位移,应力降,有限元方法

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Abstract:

力学上,地震可以看作在应力场作用下由于断层带介质的突然损伤或软化导致的断层带失稳事件.本文基于这个地震动力学模型,利用一种可以模拟断层大位错的有限元方法,研究了2011年MW9.0东日本大地震(Tohoku-Oki)的动力学破裂过程.比较了无障碍体和具有不同刚度障碍体的断层带模型产生的断层位移、位错和应力降.主要结果表明,障碍体的存在并不明显地改变障碍体区域的初始构造应力场.对有障碍体情形,准静态结果显示断层上盘最大逆冲位移和最大剪切位错分别为51m和58m,均发生在海底表面海沟处,与无障碍体的结果(最大剪切位错约55m)相比差别不大;下盘最大倾向位移(-10m)并不与上盘最大值出现在同一位置,而是在障碍体处.障碍体处剪应力降(约11MPa)大于周围非障碍体区域.障碍体处正应力降的最大值约为3MPa.模拟结果似乎不支持海山是导致本次地震异乎寻常大位错的原因,而倾向于断层带剪切刚度在地震过程中极度损伤或软化.

References

[1]  Gudmundsson A. 2004. Effects of Young''s modulus on fault displacement. Comptes Rendus Geoscience, 336(1): 85-92.
[2]  Hu C B, Zhou Y J, Cai Y E. 2009. A new finite element model in studying earthquake triggering and continuous evolution of stress field. Sci. China Ser. D-Earth Sci., 52(7): 994-1004, doi: 10.1007/S11430-009-0082-3.
[3]  Ide S, Baltay A, Beroza G C. 2011. Shallow dynamic overshoot and energetic deep rupture in the 2011 MW9.0 Tohoku-Oki earthquake. Science, 332(6036): 1426-1429, doi: 10.1126/science.1207020.
[4]  Kanamori H. 1977. The energy release in great earthquakes. J. Geophys. Res., 82(20): 2981-2876.
[5]  Lay T, Ammon C J, Kanamori H, et al. 2011. Possible large near-trench slip during the 2011 Mw9.0 off the Pacific coast of Tohoku earthquake. Earth, Planets and Space, 63(7): 687-692.
[6]  Li Y G, Vidale J E, Day S M, et al. 2002. Study of the 1999 M7.1 Hector Mine, California, earthquake fault plane by trapped waves. Bull. Seismol. Soc. Am., 92(4): 1318-1332.
[7]  Mondol N H, Bj?rlykke K, Jahren J, et al. 2007. Experimental mechanical compaction of clay mineral aggregates-Changes in physical properties of mudstones during burial. Marine and Petroleum Geology, 24(5): 289-311.
[8]  Rhea S, Tarr A C, Hayes G P, et al. 2010. Seismicity of the Earth 1900-2007, Japan and vicinity. U. S. Geological Survey, Open-File Report 2010-1083-D.
[9]  Scholz C H. 1990. The Mechanics of Earthquakes and Faulting. New York: Cambridge University Press.
[10]  Simons M, Minson S E, Sladen A, et al. 2011. The 2011 magnitude 9.0 Tohoku-Oki earthquake: Mosaicking the megathrust from seconds to centuries. Science, 332(6036): 1421-1425, doi: 10.1126/science.1206731.
[11]  Wang K L, Kinoshita M. 2013. Dangers of being thin and weak. Science, 342(6163): 1178-1180, doi: 10.1126/science.1246518.
[12]  Yamazaki Y, Lay T, Cheung K F, et al. 2011. Modeling near-field tsunami observations to improve finite-fault slip models for the 11 March 2011 Tohoku earthquake. Geophys. Res. Lett., 38(7): L00G15, doi: 10.1029/2011GL049130.
[13]  Yin Y Q. 2014. Plastic Mechanics of Rock-Like Materials (in Chinese). Beijing: Peking University Press.
[14]  Yin Y Q, Zhang H. 1982. A mathematical model of strain softening in simulating earthquake. Chinese J.Geophys.(Acta Geophysica Sinica) (in Chinese), 25(5): 414-423.
[15]  Yoshida K, Miyakoshi K, Irikura K. 2011. Source process of the 2011 off the Pacific coast of Tohoku Earthquake inferred from waveform inversion with long-period strong-motion records. Earth, Planets and Space, 63(7): 577-582.
[16]  Yue H, Lay T. 2011. Inversion of high-rate (1 sps) GPS data for rupture process of the 11 March 2011 Tohoku earthquake (MW9.1). Geophys. Res. Lett., 38(7): L00G09, doi: 10.1029/2011GL048700.
[17]  Zhang Y, Xu L S, Chen Y T. 2012. Rupture process of the 2011 Tohoku earthquake from the joint inversion of teleseismic and GPS data. Earthq. Sci., 25(2): 129-135, doi: 10.1007/s11589-012-0839-1.
[18]  Aki K. 1966. Generation and propagation of G waves from the Niigata earthquake of June 14, 1964. Part 2. Estimation of earthquake moment, released energy, and stress-strain drop from G-waves spectrum. Bulletin of the Earthquake Research Institute, 44: 73-88.
[19]  Caine J S, Evans J P, Forster C B. 1996. Fault zone architecture and permeability structure. Geology, 24(11): 1025-1028.
[20]  Chester F M, Rowe C, Ujiie K, et al. 2013. Structure and composition of the plate-boundary slip zone for the 2011 Tohoku-Oki earthquake. Science, 342(6163): 1208-1211, doi: 10.1126/science.1243719.
[21]  Duan B C. 2012. Dynamic rupture of the 2011 MW9.0 Tohoku-Oki earthquake: Roles of a possible subducting seamount. J. Geophys. Res., 117: B05311, doi: 10.1029/2011JB009124.
[22]  Fujiwara T, Kodaira S, No T, et al. 2011. The 2011 Tohoku-Oki earthquake: displacement reaching the trench axis. Science, 334(6060): 1240, doi: 10.1126/science.1211554.

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