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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017TECTONIC SETTING, SEISMOLOGICALAND TSUNAMI OBSERVATIONS

Dr. Theofilos ToulkeridisProfessor

Escuela Politécnica del Ejército (ESPE), Ecuador

Dr. Sissy Nikolaou, PE, F. ASCEPrincipal, WSP USA

Dr. Mojtaba Malek, PESenior Engineer, WSP USA

2016 Mw7.8 Ecuador EarthquakeNew York City, 5/30/17

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017OUTLINE

GEER-ATC REPORTIntroduction

SEISMIC HAZARDHistoric Seismicity · Subduction Zone

Muisne Earthquake

TSUNAMI HAZARDPrevious Tsunamis · Tsunami Hazard Assessments

Tsunami Observations after Muisne Earthquake

CONCLUSIONS

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017GEER-ATC REPORTThe Geotechnical Extreme EventsReconnaissance (GEER) Association isvolunteer organization of geotechnicalengineers, engineering geologists, andearth scientists from academia, industry,government organizations, and non-profitorganizations, with goals:

Respond to geotechnical extremeevents, conducting detailedreconnaissance and documenting theirobservations.

Obtain valuable perishable informationthat can be used to advance research andimprove engineering practice.

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

The subduction zone along Ecuador andPeru-Chile has produced destructiveearthquakes, including the largest everrecorded M9.5 of 1960 earthquake.

The epicenter of the Mw7.8 April 16,2016 earthquake was in the northerncoast of Ecuador, about 30 km SE ofMuisne in Esmeraldas.

Hypocentral depth of 21 km

Over 135 aftershocks in the first 24 hr

Two major aftershocks with Mw6.7 & 6.9in May 18, 2016

SEISMIC HAZARDSubduction Zone

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017SEISMIC HAZARDHistoric Seismicity

The seismic catalog contains records from 1587 to June 2014, includes historical andinstrumental information (Toulkeridis et al. 2017).

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017SEISMIC HAZARDSubduction Zone

Seismogenic Zoning for Ecuadorrelated to subduction (Parra, 2016)

Interfacesources

In-slab sources

seismicity of the IFNseismogenic zone(Parra et al., 2016)

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017SEISMIC HAZARDMw7.8 Muisne event

Pedernales

Manta &Portoviejo &ChoneGuayaquil

The strongest motion with PGA = 1.41 gwas recorded in the EW component ofthe APED station, with RRUP of around 20km and Vs30 of 342 m/s.(Geoestudios, 2016)

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

USGS ShakeMap

Ground motions30 stations: H1, H2, V Pedernales, PHA = 1.4 g

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

1.4 g

1.03 g

0.19 g

0.33 g

0.40 g

0.32 g

0.02 g

0.09 g

Slide: R. Luque, GEER

Ground motions, H1 (EW)

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017Landslides

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017Manta

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017Manta

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017Manta

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017GMPE, Recorded motions

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017NEC-15 - Geomean spectra

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017TSUNAMI HAZARDPrevious tsunamis

In the past two centuries, the Ecuadorian shoreline hasexperienced a dozen impacts of tsunamis:

1906 (Mw8)1942 (Mw7.8)1958 (Mw7.7)1979 (Mw8.2)

Panoramic view of the morphology of western Ecuador and locationof seismic epicenters, which generated tsunamis in the last 110 years(Adapted and modified from Collot et al., 2004).

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Max tsunami wave height of ~6 m at San Juan de laCosta, causing 300-600 deaths.(NGC, 2012).

TSUNAMI HAZARDPrevious tsunamis

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Photo and Record of 1979 tsunami as recorded inEsmeraldas (Pararas-Carayannis, 1980)

• Tsunami record from the Esmeraldas port, ~ 95 nautical misouth of the epicenter.

• 1st wave hit the coast ~3 min after the earthquake, with atotal of 3 - 4 waves. The 3rd wave was the highest andcoincided with low tide, greatly reducing the inundation by1-3 m and the likely death toll (NGC, 2012).

TSUNAMI HAZARDPrevious tsunamis

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

• Magnitude Mw 8.8, concordant with the Mmax obtained by analysis of the trend of seismicity at itsmaximum value in the IFN zone

• Magnitude Mw 8.1, which constitutes the lower limit of the uniform probability distribution obtained fromthe estimation of the random uncertainty inherent to the maximum magnitude Mmax for the IFN zone.

• Magnitude Mw 7.5 to a distance range of 30-60 km from the calculation point (Latitude 0.9871, Longitude -79.6558), concordant with the Earthquake Control obtained from the seismic hazard breakdown forEsmeraldas

=5+0.65 lnT ℎ0=3.75x10−6x (1.8 ) ℎ0 is the wave height

When the wave meets the continental platform, the wave breaks with a height equal to Kryukov andButenko (2013) :

ℎ =1.5xℎ

TSUNAMI HAZARDNumerical Calculator

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Tsunami and subsequent floodinghazard map for the event of apotential Mw 8.8 (Toulkeridis etal., 2017).

Tsunami and subsequent flooding hazard map for the potentialevents of Mw 7.5 and Mw 8.1 (Toulkeridis et al., 2017)

TSUNAMI HAZARDNumerical Calculator

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

• The tsunami was registered locally by the INOCAR-DART buoy, which is close to theepicenter, immediately after the earthquake.

• It has been difficult to differentiate the tsunami signal from the noise produced by theearthquakes

TSUNAMI HAZARDMw7.8 Muisne event

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Muisne event triggered a tsunami,registered by NOAA 32411 and 32413DART buoys in the Panama and Perubasins.The seismic waves propagated overthe seabed, affecting the register atthe pressure sensor of these buoysuntil one hour after the earthquake

TSUNAMI HAZARDMw7.8 Muisne event

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Small boat and buoyswere moved from theiranchors due to thetsunami at Esmeraldasport (ECU911)

TSUNAMI HAZARDMw7.8 Muisne event

2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

The Muisne event was significantly stronger than NEC and BChydro spectra.The tsunami generated after the April 16 event was minor and did not inducesignificant additional damage to coastal areas.Continental earthquakes can cause tsunamis, as in the 2016 Muisneearthquake. Under water landslides can cause tsunamis.The 2016 tsunami hit at low tide, causing no inundation or major physicaleffects at the coastlines.

CONCLUSIONS

REFERENCESGEER-ATC Earthquake Reconnaissance April 16th 2016, Muisne, Ecuador, October, 2016.www.geerassociation.org , Nikolaou S., Vera, X., Gilsanz, R. (eds)Contrasting Results of Potential Tsunami Hazards in Muisne, Central Coast of Ecuador, 2017.Toulkeridis, T. et al.Parra H., Benito, M.B., Gaspar-Escribano, J. M., 2016. Seismic Hazard Assessment incontinental Ecuador. Bulletin of Earthquake Engineering, 14,(8): 2129–2159.

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2016 Mw7.8 Ecuador Earthquake: Relevance to NYC & US Critical InfrastructureEERI-NYNE and ASCE Met Section Infrastructure Group Mini-Symposium

Tectonic Setting,Seismological andTsunami Observations

Dr. S. Nikolaou, WSP USAGSMT, New York City

May 30, 2017

Thank You!