Tsunami Science Four Years after the 2004 Indian Ocean Tsunami Part II: Observation and Data Analysis Edited by Phil R. Cummins Laura S. L. Kong Kenji Satake Birkhäuser Basel · Boston · Berlin Reprint from Pure and Applied Geophysics (PAGEOPH), Volume 166 (2009) No. 1/2 Phil R. Cummins Laura S. L. Kong Geoscience Australia UNESCO Intergovernmental Oceanographic P.O. Box 378 Commission (IOC) Canberra, ACT 2601 International Tsunami Information Centre Australia 737 Bishop Street Email: [email protected] Suite 2200 Honolulu, HI, 96813 Kenji Satake USA Earthquake Research Institute Email: [email protected] University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-0032 Japan Email: [email protected] Library of Congress Control Number: 2009920437 Bibliographic information published by Die Deutsche Bibliothek: Die Deutsche Bibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at <http://dnb.ddb.de> ISBN 978-3-0346-0063-7 Birkhäuser Verlag AG, Basel · Boston · Berlin This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustra- tions, recitation, broadcasting, reproduction on microfilms or in other ways, and storage in data banks. For any kind of use, permission of the copyright owner must be obtained. © 2009 Birkhäuser Verlag AG Basel · Boston · Berlin P.O. Box 133, CH-4010 Basel, Switzerland Part of Springer Science+Business Media Printed on acid-free paper produced from chlorine-free pulp. TCF ∞ Cover graphic: Based on a picture provided Dr. Pål Wessel, Department of Geology and Geophysics, School of Ocean and Earth Science and Technology (SOEST), University of Hawaii at Manoa, Honolulu, USA. Printed in Germany ISBN 978-3-0346-0063-7 e-ISBN 978-3-0346-0064-4 9 8 7 6 5 4 3 2 1 www.birkhauser.ch Contents 1 Introduction to ‘‘Tsunami Science Four Years After the 2004 Indian Ocean Tsunami,PartII:ObservationandDataAnalysis’’ P.R.Cummins,L.S.L.Kong,K.Satake 9 FieldSurveyandGeologicalEffectsofthe15November2006KurilTsunami intheMiddleKurilIslands B.T.MacInnes,T.K.Pinegina,J.Bourgeois,N.G.Razhigaeva, V.M.Kaistrenko,E.A.Kravchunovskaya 37 The November 15, 2006 Kuril Islands-Generated Tsunami in Crescent City, California L.Dengler,B.Uslu,A.Barberopoulou,S.C.Yim,A.Kelly 55 Validation and Joint Inversion of Teleseismic Waveforms for Earthquake Source Models Using Deep Ocean Bottom Pressure Records: A Case Study ofthe2006KurilMegathrustEarthquake T.Baba,P.R.Cummins,H.K.Thio,H.Tsushima 77 Variable Tsunami Sources and Seismic Gaps in the Southernmost Kuril Trench:AReview K.Hirata,K.Satake,Y.Tanioka,Y.Hasegawa 97 In situ Measurements of Tide Gauge Response and Corrections of Tsunami WaveformsfromtheNiigatakenChuetsu-okiEarthquakein2007 Y.Namegaya,Y.Tanioka,K.Abe,K.Satake,K.Hirata,M.Okada, A.R.Gusman 117 ExcitationofResonantModesalongtheJapaneseCoastbythe1993and1983 TsunamisintheJapanSea K.Abe 131 Numerical Study of Tsunami Generated by Multiple Submarine Slope FailuresinResurrectionBay,Alaska,duringtheM 9.21964Earhquake W E.Suleimani,R.Hansen,P.J.Haeussler 153 LituyaBayLandslideImpactGeneratedMega-Tsunami50thAnniversary H.M.Fritz,F.Mohammed,J.Yoo 177 TsunamisonthePacificCoastofCanadaRecordedin1994–2007 F.E.Stephenson,A.B.Rabinovich 211 The 15 August 2007 Peru Earthquake and Tsunami: Influence of the Source CharacteristicsontheTsunamiHeights H.He´bert,D.Reymond,Y.Krien,J.Vergoz,F.Schindele´,J.Roger, A.Loevenbruck 233 Tide Gauge Observations of 2004–2007 Indian Ocean Tsunamis from SriLankaandWesternAustralia C.B.Pattiaratchi,E.M.S.Wijeratne 259 Reconstruction of Tsunami Inland Propagation on December 26, 2004 inBandaAceh,Indonesia,throughFieldInvestigations F.Lavigne,R.Paris,D.Grancher,P.Wassmer,D.Brunstein,F.Vautier, F.Leone,F.Flohic,B.DeCoster,T.Gunawan,C.Gomez,A.Setiawan, R.Cahyadi,Fachrizal 283 The1856TsunamiofDjidjelli(EasternAlgeria):Seismotectonics,Modelling andHazardImplicationsfortheAlgerianCoast A.Yelles-Chaouche,J.Roger,J.De´verche`re,R.Brace`ne,A.Domzig, H.He´bert,A.Kherroubi 301 Analysis of Observed and Predicted Tsunami Travel Times for the Pacific andIndianOceans P.Wessel Pureappl.geophys.166(2009)1–7 (cid:2)Birkha¨userVerlag,Basel,2009 0033–4553/09/010001–7 Pure and Applied Geophysics DOI10.1007/s00024-009-0442-0 Introduction to ‘‘Tsunami Science Four Years After the 2004 Indian Ocean Tsunami, Part II: Observation and Data Analysis’’ PHIL R. CUMMINS,1 LAURA S. L. KONG,2 and KENJI SATAKE3 Abstract—InthisintroductionwebrieflysummarizethefourteencontributionstoPartIIofthisspecialissue onTsunamiScienceFourYearsAfterthe2004IndianOceanTsunami.Thesepapersarerepresentativeofthe newtsunamisciencebeingconductedsincetheoccurrenceofthattragicevent.Mostofthesewerepresentedat the session: Tsunami Generation and Hazard, of the International Union of Geodesy and Geophysics XXIV GeneralAssemblyheldatPerugia,Italy,inJulyof2007.Thatsessionincludedoveronehundredpresentations onawiderangeoftopicsintsunamiresearch.ThepapersgroupedintoPartII,andintroducedhere,coverfield observationsofrecenttsunami’s,modernstudiesofhistoricalevents,coastalsea-levelobservationsandcase studiesintsunamidataanalysis. Keywords: Tsunami,tidegauge,sealevel,waveforminversion,seiche,harborresonance,numerical modeling,post-tsunamisurvey,tsunamiwarningsystem,runup. 1. Introduction During the years following the 2004 Sumatra-Andaman Earthquake and subsequent Indian Ocean Tsunami (IOT), the world experienced a remarkable series of great earthquakes.The2004eventmarkedthebeginningofaseriesofearthquakesoffSumatra that included three of the ten largest earthquakes recorded since 1900 (http://earth- quake.usgs.gov).Duringtheperiod2004–2007,nineearthquakesofmagnitude8orgreater occurredintheIndianandPacificOceans;allofwhichgeneratedtsunami’s,ofwhichsix werelargeenoughtocausedamage.Theseeventscoincidedwithaperiodofrapidgrowthin tsunami science spurred by the IOT disaster, including an expansion in earthquake and tsunamiobservationplatforms,aswellasdramaticimprovementsintechnologyandfield techniques. Many observational studies of these and other events were presented in the session: Tsunami Generation and Hazard, at the International Union of Geodesy and Geophysics XXIV General Assembly in Perugia, Italy, held in July of 2007. Over 1 GeoscienceAustralia,GPOBox378,Canberra,ACT2601,Australia.E-mail:[email protected] 2 UNESCOIOCInternationalTsunamiInformationCentre,737BishopSt.,Ste.2200,Honolulu,Hawaii 96813,U.S.A,E-mail:[email protected]. 3 EarthquakeResearchInstitute,UniversityofTokyo,1-1-1Yayoi,Bunkyo-ku,Tokyo113-0032,Japan E-mail:[email protected] 2 P.R.Cumminsetal. Pureappl.geophys., one hundred presentations were made at this session, spanning topics ranging from paleo-tsunami research, to nonlinear shallow-water theory, to tsunami hazard and risk assessment.Aselectionofthisworkispublishedindetailinthe28papersofthespecial issueofPureandAppliedGeophysics. Inthisintroductorypaper,webrieflydiscussthepapersinthissecondpartofTsunami Science Four Years after the 2004 Indian Ocean Tsunami. In Section 2 we discuss field observationsofrecenttsunamis,whileSection 3describessomemodernstudiesofhistorical events.Section 4discussestidegaugeobservationsandSection 5dataanalysiscasestudies. 2. Field Observations of Recent Tsunamis Each damaging tsunami resulting from the series of great tsunamigenic earthquakes that occurred in 2004–2007 was followed by one or more post-tsunami surveys, and reports on three of these surveys appear in this volume. Careful observations of actual tsunami impacts, such as those presented in these reports, are invaluable for understanding tsunami runup and inundation, validating numerical tsunami models, andforinterpretinggeologicalsignaturesofpaleo-tsunamis.Thestudiesdescribedbelow demonstrate how post-tsunami field observations can be used to infer detailed characteristics of the causative tsunami, to determine what factors influence inundation and runup, and to inform tsunami warning procedures. LAVIGNEetal.(2009)providedacomprehensivesummaryofthreemonthsoftsunami fieldsurveysfromBandaAcehandLhokNga,Indonesiaintheaftermathofthe2004Indian Oceantsunami.Runup,waveheights,flowdepthsanddirections,eventchronologiesand buildingdamagepatterns,inundationmaps,high-resolutiondigitalelevationmodelswere collectedandcompiled.Theyreportedthatapproximately10separatewavesaffectedthe region, and that the largest runups measured about 35 m with a maximum of 51 m; the highestvaluemeasuredinhumanhistoryfromaseismically-generatedtsunami.Theopen- sourcedatabaseisbeingmadeavailabletothecommunityunderthecooperativeFrench- IndonesianTSUNARISQUEprogramtoassistinbettercalibratingnumericalmodels. MACINNES et al. (2009) reported the results of their post-tsunami field survey of the M 8.3KurilEarthquake,which occurred on15November2006,inthe middleofKuril w Islands.Fortunately,theyvisitedtheislandsforapaleo-tsunamisurveyinthesummerof 2006,threemonthsbeforetheearthquake,hencetheycouldcomparevisualobservations, photographs and measurements of topographic profiles taken before and after the tsunami. While the November 2006 earthquake was followed by the January 2007 earthquake,thetsunamifromthelatterwas smallerthan thatfromtheformer,hence the authors attributed the geological traces of tsunamis to the 2006 earthquake. They found that the tsunami heights strongly depended on the local topography, and averaged about 10 mwithamaximumofmorethan20 m.Wherever sandwasavailable,itwasbrought inlandanddepositedwithlandwardthinningandfiningfeatures.Similartsunamideposits from previous earthquakes were also found. They also described significant coastal Vol.166,2009 IntroductiontoTsunamiScienceFourYearsAfterthe2004 3 erosion features, such as scours, soil stripping, rock plucking or cliff retreat, at places where the runup heights were more than 10 m. Theeffectsofthe2006KurilEarthquakewerealsoexperiencedinthefarfield.DENGLER etal.(2009)reportedontheimpactofthiseventinCrescentCity,California,wherelater- arrivingmaximumwavesandstrongcurrentsinexcessof10knotsoveran8-hourperiod causedanestimatedUS$9.2millionofdamagetoharbordocksdespiteitsarrivalatlow tide.CrescentCityisknowntobehistoricallyvulnerabletotsunamisbecauseofitscoastal andunderseamorphology.Asaresultofthe2006tsunami,andtoadvisecoastalofficials that local conditions can cause wave amplification and strong currents, the West Coast/ AlaskaTsunamiWarningCenterredefineditsAdvisorytocautionthatcoastalthreatsmay stillpersisteventhoughsignificantwidespreadinundationwasnotexpectedforallregions. Theauthors alsoemphasized theimportant roleofawarenessasbeingakeyfortsunami safety,especiallywhenonlymodesttsunamisareexpected. 3. Modern Studies of Historical Events Severalpapersinthisvolumeaddresstheneedtounderstandhistoricaleventsinorder to correctly infer what implications they may have for tsunamihazard. Historical events aremostoftenstudiedbycombiningfieldobservationsofthetypedescribedabove,with numerical or laboratory modeling, which can elucidate their source mechanisms. As demonstrated in the papers described below, an accurate understanding of the source mechanisms of historical tsunami events is important for assessing the potential for the occurrence of similar events. SULEIMANIetal.(2009)usedaviscousslidemodelcoupledwithshallowwaterequations tosuccessfullymodellandslidesandtheensuinglocaltsunamiwavesinResurrectionBay,a glacial fjord in south-central Alaska, after the M 9.2 1964 Prince William Sound w earthquake. The numerical results, in good agreement with eyewitness reports and other observationaldata,showedthatthreeunderwaterslopefailureswerethemajorcontributors to the tsunami that attacked Seward, Alaska less than five minutes after the earthquake. Theirmodellingapproachwasshowntobeausefultoolforestimatinglandslidetsunami hazard, and their work demonstrated the need to consider these hazards inAlaska fjords whereglacialsedimentsareaccumulatingathighratesonsteepunderwaterslopes. FRITZ et al. (2009) summarized two- and three-dimensional physical laboratory experimentsthatusedapneumaticlandslidetsunamigeneratortomodelthe1958Lituya Bay landslide tsunami, resulting in the highest wave runup (524 m) in recorded history. State-of-the-art measurement techniques were used to measure and photograph the landslide-water impact and wave generation. The two-dimensional velocity vector field showed the impact to be divided into two stages: (a) Impact and penetration with flow separation, cavity formation, and wave generation, and (b) air cavity collapse with landslide run-out and debris entrainment. The results were compared with other predictive relationships for amplitude and height since no actual tsunami heights are 4 P.R.Cumminsetal. Pureappl.geophys., available.Becausethislandslide-generatedtsunamiexhibitedstrongenergydirectivity,a three-dimensional physical model was constructed, and the surface velocities measured forfuturevalidationandbenchmarking,usingdetailedbathymetryinathree-dimensional numerical simulation. YELLES-CHAOUCHE et al. (2009) investigated the tsunamis generated from the 1856 Djidjelliearthquakes.Historicalseismicintensityandtsunamiwaveinformation,combined withseismicityoverthepast30 yearsandbathymetricandseismicreflectionlinescollected in2005,wereusedtocharacterizetheseismotectonicsoftheregionandtoinferthesource ruptureofthemainearthquakeandtsunamisource.Thenumericalmodelresultsshowed thatmuchoftheeasternAlgeriancoastandBalearicIslandswereaffected,withamaximum wave height of 1.5 m near the harbor of Djidjelli. This event, together with the 2003 Bourmerdestsunami,demonstratethattheAlgerianmarginhostsseveralactivetsunami- genicfaultsthatcouldcausedamagetothewesternMediterraneanandAlgeriancoasts. HIRATA et al. (2009) reviewed multiple occurrences of tsunamigenic earthquakes alongthesouthernKurilsubductionmegathrust;oneofthefewareasintheworldwhere onecan testthecontentionthatearthquakeruptureoccursalongcharacteristicsegments. Tsunami data, both historic (tide gauge, field measurements, and eyewitness observa- tions) and prehistoric (tsunami deposits), are used to provide information on rupture extent. The authors’ interpretation of past studies indicates that there is substantial variability of rupture from event to event, suggesting that the idea that earthquakes repeatedly rupture characteristic segments is an oversimplification. 4. Coastal Sea-level Gauge Observations of Tsunamis Sea-level records from coastal tide gauge stations provide some of the most detailed informationavailableontsunamisourcesignaturesandtsunamiinteractionwithshallow bathymetry. They therefore have great potential to improve our understanding of potential coastal impacts of future tsunami’s. They are also a critical source of information for tsunami warning systems to confirm generation of a tsunami (though data from DART (Deep-ocean Assessment and Reporting of Tsunamis) buoys are also being used for this purpose). For these reasons, understanding the quality of data from coastal tide gauges and what influences the signals recorded on them is of great importanceinbothprogressingtsunamiscienceandsupportingtsunamimitigation.Four papers in this special issue dealt with sea-level data recorded by coastal gauges, STEPHENSONandRABINOVICH(2009),NAMEGAYAetal.(2009),PATTIARATCHIandWIJERATNE (2009), and ABE (2009). STEPHENSON and RABINOVICH (2009) compiled tsunami instrumental data recorded on the Pacific Coast of Canada in 1994–2007. During these 15 years, 16 tsunamis were recorded. Eleven of these were from distant sources around the Pacific Ocean and the 2004IndianOceantsunami.ThreewerefromlocalearthquakesinCanadaandaregional event in California, and two were of meteorological origin. Through their analysis, they