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Observations and Modeling of the August 27, 2012 Earthquake and Tsunami affecting El Salvador and Nicaragua


On 27 August 2012 (04:37 UTC, 26 August 10:37 p.m. local time) a magnitude M w = 7.3 earthquake occurred off the coast of El Salvador and generated surprisingly large local tsunami. Following the event, local and international tsunami teams surveyed the tsunami effects in El Salvador and northern Nicaragua. The tsunami reached a maximum height of ~6 m with inundation of up to 340 m inland along a 25 km section of coastline in eastern El Salvador. Less severe inundation was reported in northern Nicaragua. In the far-field, the tsunami was recorded by a DART buoy and tide gauges in several locations of the eastern Pacific Ocean but did not cause any damage. The field measurements and recordings are compared to numerical modeling results using initial conditions of tsunami generation based on finite-fault earthquake and tsunami inversions and a uniform slip model.

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  • Abe, K., Tsuji, Y., Imamura, F., Katao, H., Iio, Y., Satake, K., Bourgeois, J., Noguera, E., and Estrada, F. (1993), Field Survey of the Nicaragua Earthquake and Tsunami of September 2, 1992, Bulletin of the Earthquake Research Institute of the University of Tokyo (in Japanese), 68, 23–70.

  • Álvarez-Gómez, J. A., Aniel-Quiroga, Í., Gutiérrez-Gutiérrez, O. Q., Larreynaga, J., González, M., Castro, M., Gavidia, F., Aguirre-Ayerbe, I., González-Riancho, P., and Carreño, E. (2013), Tsunami hazard assessment in El Salvador, Central America, from seismic sources through flooding numerical models, Natural Hazards and Earth System Science, 13, 2927–2939. doi:10.5194/nhess-13-2927-2939.

  • Bassin, C., Laske, G., and Masters, G. (2000), The Current Limits of Resolution for Surface Wave Tomography in North America, EOS Trans AGU, 81, F897.

  • Boatwright, J., and Choy, G. L. (1986), Telesesismic estimates of the energy radiated by shallow earthquakes, Journal of Geophysical Research-Solid Earth and Planets, 91(B2), 2095–2112.

    Google Scholar 

  • Borrero, J. C. (2012), Field Survey Report of Tsunami Effects Caused by the August, 2012 Offshore El Salvador Earthquake, UNESCO/IOC report.

  • Convers, J. A., and Newman, A. V. (2011), Global Evaluation of Large Earthquake Energy from 1997 Through mid-2010, J. Geophys. Res., 116, B08304, doi:10.1029/2010JB007928.

  • Dean, R. G., and Dalrymple, R. A., Water Wave Mechanics for Engineers and Scientists (World Scientific, Teaneck, NJ, 1991).

  • Fernandez, M., Ortiz-Figueroa, M., and Mora, R. (2004), Tsunami Hazards in El Salvador, in Rose, W., Bommer, J., Lopez, D., Carr, M., and Major, J. eds. Natural Hazards in El Salvador, Boulder Colorado. Geological Society of America, Special Paper 375. pp. 435–444.

  • Heidarzadeh, M., and Satake, K. (2014), The El Salvador and Philippines tsunami of August 2012: insights from sea level data analysis and numerical modeling. Pure and Applied Geophysics. doi:10.1007/s00024-014-0790-2

  • Hill, E, Borrero, J., Huang, Z., Qiu, Q., Banerjee, P., Natawidjaja, D., Elosegui, P., Fritz, H., Pranantyo, I., Li, L., Macpherson, K., Skanavis, V., Synolakis, C., and Sieh, K. (2012), The 2010 Mw 7.8 Mentawai earthquake: Very shallow source of a rare tsunami earthquake determined from tsunami field survey and near-field GPS. Journal of Geophysical Research, Vol 117, B06402, doi:10.1029/2012JB009159.

  • Houston, H. (2001), Influence of depth, focal mechanism, and tectonic setting on the shape and duration of earthquake source time functions, J. Geophys. Res.-Solid Earth, 106(B6), 11137–11150.

    Google Scholar 

  • Ji, C., Wald, D. J. and Helmberger, D. V. (2002), Source description of the 1999 Hector Mine, California earthquake; Part I: Wavelet domain inversion theory and resolution analysis, Bull. Seism. Soc. Am., Vol 92, No. 4. pp. 1192–1207.

    Google Scholar 

  • Kanamori, H. (1972), Mechanism of Tsunami Earthquakes, Physics of the Earth and Planetary Interiors, 6, 346–359.

  • Kanamori, H. and Kikuchi, M. (1993), The 1992 Nicaragua earthquake: a slow tsunami earthquake associated with subducted sediments. Nature, 361, 714–716.

  • Kelleher, J. A. (1972), Rupture zones of large South-American earthquakes and some predictions, J. Geophys. Res., 77(11), 2087–2103, doi:10.1029/JB077i011p02087.

  • Lynett, P., Weiss, R., Renteria, W., De La Torre Morales, G., Son, S., Arcos, M. and MacInnes, B. (2013), Coastal Impacts of the March 11th Tohoku, Japan Tsunami in the Galapagos Islands. Pure Appl. Geophys. 170(6–8):1189–1206, doi:10.1007/s00024-012-0568-3.

  • MATLAB and Statistics Toolbox Release 2012, The MathWorks, Inc., Natick, Massachusetts, United States.

  • McKenzie, D., and Jackson J. (2012), Tsunami earthquake generation by the release of gravitational potential energy, Earth and Planetary Science Letters, 345–348, 1–8.

  • Newman, A. V., Hayes G., Wei Y., and Convers J. (2011), The 25 October 2010 Mentawai tsunami earthquake, from real-time discriminants, finite-fault rupture, and tsunami excitation, Geophys. Res. Lett., 38, L05302, doi:10.1029/2010GL046498.

  • Newman, A. V., and Okal, E. A. (1998), Teleseismic estimates of radiated seismic energy: The E/M0 discriminant for tsunami earthquakes, J. Geophys. Res., 103, 26885–26898.

    Google Scholar 

  • Okada, Y. (1985), Surface deformation due to shear and tensile faults in a half-space, Bulletin of the Seismological Society of America, 75, 1135–1154.

  • Satake, K., Bourgeois, J., Abe, K., Abe, K., Tsuji, Y., Immura, F., Iio, Y., Katao, H., Noguera, E., and Estrada, F. (1994), Tsunami Field Survey of the 1992 Nicaragua Earthquake, Eos: Trans. Am. Geophys. Un. 74,13, pp 145, 156–157.

  • Synolakis, C. E., and Okal, E. A. (2005), 1992–2002: Perspective on a decade of post-tsunami surveys, in: Tsunamis: Case studies and recent develop- ments, ed. K. Satake, Adv. Nat. Technol. Hazards, 23:1–30.

  • Tanioka, Y., and Satake, K. (1996), Tsunami generation by horizontal displacement of ocean bottom, Geophysical Research Letters, Volume 23, Issue 8, pp. 861–864.

  • Titov, V., and González, F. I. (1997), Implementation and testing of the Method of Splitting Tsunami (MOST) model, NOAA Tech. Memo. ERL PMEL‐112 (PB98‐122773), 11 pp., Pac. Mar. Environ. Lab., NOAA, Seattle, Wash.

  • UNESCO (2013), International Tsunami Survey Team (ITST), Post-Tsunami Survey Field Guide. 2nd Edition. Dominey-Howes, D. and Dengler, L. eds., IOC Manuals and Guides No. 37, Paris: (English).

  • US Geological Survey (2012),

  • White, R. A., Lígoria, J. P., and Cifuentes, I. L. (2004), “Seismic history along the Middle America subduction zone along El Salvador, Guatemala and Chiapas, Mexico: 1526-2000”. In Rose, William Ingersol (et al.) (Eds). Natural Hazards in El Salvador. Geological Society of America, Special Paper 375. pp. 379–96. ISBN:0-8137-2375-2.

  • Ye, L., Lay T., and Kanamori, H. (2013), Large earthquake rupture variations on the Middle America megathrust, Earth and Planetary Science Letters, 381, pp. 147–155.

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We would like to acknowledge Francisco Gavidia-Medina, Jeniffer Larreynaga-Murcia, Rodolfo Torres-Cornejo, Manuel Diaz-Flores, Fabio Alvarado and rest of the staff at MARN for logistical support, assistance during the field survey and excellent hospitality. Norwin Acosta of INETER conducted the survey of the sites in Nicaragua. Other field survey participants included Nicolas Arcos, Diego Arcas, and Julie Leonard. Laura Kong and the International Tsunami Information Center provided logistical and organizational support to the field survey. The Fuerza Aérea Salvadoreña provided the opportunity for an aerial survey by helicopter of the tsunami-affected area.

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Correspondence to Jose C. Borrero.

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Figure S1. Modeled maximum tsunami wave heights for the linearly-scaled finite fault distribution. a) S1 scaled by 1.92, and b) S2 scaled by 2.55. (PNG 187 kb)



For Source 2, we use a scaling approach similar to that used in Newman et al. (2011) for the 2010 earthquake and tsunami in the Mentawai Islands offshore Sumatra, Indonesia. Following this, an appropriate scaling parameter for the displacement along the fault plane can be determined from the following relationship:

$$ D/D_{0} = \left( {V_{{{\text{S}} - {\text{ref}}}} /V_{\text{S}} } \right)^{2} , $$

where D/D 0 is the ratio of the scaled to original slip, V S-ref is a reference shear wave velocity for the region where the earthquake occurred, and V S is the actual shear wave velocity deduced from teleseismic observations of the event and is calculated from the earthquake rupture velocity (V R) by assuming that V S = 1.25 V R. In general, since V R can be highly variable, individual V S values are calculated for each subfault in the finite fault solution, However, inspection of the finite fault model from this event reveals a consistent rupture velocity (V R) of approximately 2.25 km/s, yielding a shear wave velocity (V S) 2.81 km/s. From the Crust 2.0 model (Bassin et al. 2000) used in the finite fault analysis, the V S-ref along the sections of greatest slip is assumed to be 3.9 km/s. Using these values in Eq. 1 leads to an average scale factor of 1.92. We note that this factor is much less than what was deduced from the 2010 Mentawai event where rupture velocities in the main slip zones were often around 1.5 km/s. In using this approach, we emphasize that this is only a first-order approximation, as pointed out in Newman et al. (2011). This is primarily due to the fact that seismic excitation at teleseismic distances includes some upper-plate signal that cannot be fully deconvolved leading to an overamplification of the result. Secondly, because the solution is entirely based on the square of the determination of rupture velocity, any inaccuracies in the solution of V R can have a very large impact on the final scale factor.

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Borrero, J.C., Kalligeris, N., Lynett, P.J. et al. Observations and Modeling of the August 27, 2012 Earthquake and Tsunami affecting El Salvador and Nicaragua. Pure Appl. Geophys. 171, 3421–3435 (2014).

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  • Seismic Moment
  • Tsunami Wave
  • Slip Distribution
  • Tsunami Height
  • Tsunami Effect