Did a submarine landslide contribute to the 2011 Tohoku tsunami?

Handle URI:
http://hdl.handle.net/10754/552381
Title:
Did a submarine landslide contribute to the 2011 Tohoku tsunami?
Authors:
Tappin, David R.; Grilli, Stephan T.; Harris, Jeffrey C.; Geller, Robert J.; Masterlark, Timothy; Kirby, James T.; Shi, Fengyan; Ma, Gangfeng; Thingbaijam, Kiran Kumar ( 0000-0002-2415-2266 ) ; Mai, Paul Martin ( 0000-0002-9744-4964 )
Abstract:
Many studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recorded at three nearshore buoys off Sanriku, nor the timing and dispersion properties of the waveforms at offshore DART buoy #21418. (3) The rupture centroids obtained by tsunami inversions are biased about 60 km NNE of that obtained by the Global CMT Project. Based on an analysis of seismic and geodetic data, together with recorded tsunami waveforms, we propose that, while the primary source of the tsunami was the vertical displacement of the seafloor due to the earthquake, an additional tsunami source is also required. We infer the location of the proposed additional source based on an analysis of the travel times of higher-frequency tsunami waves observed at nearshore buoys. We further propose that the most likely additional tsunami source was a submarine mass failure (SMF—i.e., a submarine landslide). A comparison of pre- and post-tsunami bathymetric surveys reveals tens of meters of vertical seafloor movement at the proposed SMF location, and a slope stability analysis confirms that the horizontal acceleration from the earthquake was sufficient to trigger an SMF. Forward modeling of the tsunami generated by a combination of the earthquake and the SMF reproduces the recorded on-, near- and offshore tsunami observations well, particularly the high-frequency component of the tsunami waves off Sanriku, which were not well simulated by previous models. The conclusion that a significant part of the 2011 Tohoku tsunami was generated by an SMF source has important implications for estimates of tsunami hazard in the Tohoku region as well as in other tectonically similar regions.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Did a submarine landslide contribute to the 2011 Tohoku tsunami? 2014, 357:344 Marine Geology
Journal:
Marine Geology
Issue Date:
28-Sep-2014
DOI:
10.1016/j.margeo.2014.09.043
Type:
Article
ISSN:
00253227
Additional Links:
http://linkinghub.elsevier.com/retrieve/pii/S0025322714002898
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorTappin, David R.en
dc.contributor.authorGrilli, Stephan T.en
dc.contributor.authorHarris, Jeffrey C.en
dc.contributor.authorGeller, Robert J.en
dc.contributor.authorMasterlark, Timothyen
dc.contributor.authorKirby, James T.en
dc.contributor.authorShi, Fengyanen
dc.contributor.authorMa, Gangfengen
dc.contributor.authorThingbaijam, Kiran Kumaren
dc.contributor.authorMai, Paul Martinen
dc.date.accessioned2015-05-06T13:27:03Zen
dc.date.available2015-05-06T13:27:03Zen
dc.date.issued2014-09-28en
dc.identifier.citationDid a submarine landslide contribute to the 2011 Tohoku tsunami? 2014, 357:344 Marine Geologyen
dc.identifier.issn00253227en
dc.identifier.doi10.1016/j.margeo.2014.09.043en
dc.identifier.urihttp://hdl.handle.net/10754/552381en
dc.description.abstractMany studies have modeled the Tohoku tsunami of March 11, 2011 as being due entirely to slip on an earthquake fault, but the following discrepancies suggest that further research is warranted. (1) Published models of tsunami propagation and coastal impact underpredict the observed runup heights of up to 40 m measured along the coast of the Sanriku district in the northeast part of Honshu Island. (2) Published models cannot reproduce the timing and high-frequency content of tsunami waves recorded at three nearshore buoys off Sanriku, nor the timing and dispersion properties of the waveforms at offshore DART buoy #21418. (3) The rupture centroids obtained by tsunami inversions are biased about 60 km NNE of that obtained by the Global CMT Project. Based on an analysis of seismic and geodetic data, together with recorded tsunami waveforms, we propose that, while the primary source of the tsunami was the vertical displacement of the seafloor due to the earthquake, an additional tsunami source is also required. We infer the location of the proposed additional source based on an analysis of the travel times of higher-frequency tsunami waves observed at nearshore buoys. We further propose that the most likely additional tsunami source was a submarine mass failure (SMF—i.e., a submarine landslide). A comparison of pre- and post-tsunami bathymetric surveys reveals tens of meters of vertical seafloor movement at the proposed SMF location, and a slope stability analysis confirms that the horizontal acceleration from the earthquake was sufficient to trigger an SMF. Forward modeling of the tsunami generated by a combination of the earthquake and the SMF reproduces the recorded on-, near- and offshore tsunami observations well, particularly the high-frequency component of the tsunami waves off Sanriku, which were not well simulated by previous models. The conclusion that a significant part of the 2011 Tohoku tsunami was generated by an SMF source has important implications for estimates of tsunami hazard in the Tohoku region as well as in other tectonically similar regions.en
dc.relation.urlhttp://linkinghub.elsevier.com/retrieve/pii/S0025322714002898en
dc.rightsArchived with thanks to Marine Geology. http://creativecommons.org/licenses/by/3.0/en
dc.subjecttsunamien
dc.subjectsubmarine mass failureen
dc.subjectearthquakeen
dc.subjectTohokuen
dc.subjectmodelingen
dc.titleDid a submarine landslide contribute to the 2011 Tohoku tsunami?en
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalMarine Geologyen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionBritish Geological Survey, Keyworth, Nottingham, UKen
dc.contributor.institutionDepartment of Ocean Engineering, University of Rhode Island, Narragansett, RI, USAen
dc.contributor.institutionDepartment of Earth and Planetary Science, Graduate School of Science, University of Tokyo, Tokyo, Japanen
dc.contributor.institutionDepartment of Geology and Geological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, USAen
dc.contributor.institutionCenter for Applied Coastal Research, University of Delaware, Newark, DE, USAen
dc.contributor.institutionDepartment of Civil and Environmental Engineering, Old Dominion University, Norfolk, VA, USAen
kaust.authorThingbaijam, Kiran Kumaren
kaust.authorMai, Paul Martinen
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.