Dec292015Mag4.8

EarthquakeTuesday,11:39PMlocalAmeLocated17kmNNEofVictoria(80kmsouthofUBC)“Deep”intraslabearthquake

at52kmdepthFeltacrosssouthernVancouverIslandandLowerMainlandNosignificantdamageNocasualAes

Earthquakesoccureveryday:hXp://earthquake.usgs.gov/earthquakes/map/

USGSNaAonalEarthquakeInformaAonCenter

Globalseismicity1975-1995

a"erPeacockandWang(1999,Science)

‘Wehavetoworryaboutamagnitude-7-to7.5intraslabearthquakelocated31milesbeneathSeaAleorVancouver.’geologistSimonPeacocksays.USAToday,Oct.29,1999

2001 Nisqually (Olympia) Earthquake •  Feb.28,2001,10:55AM•  Mw=6.8•  Depth=52km•  LocatedbetweenTacomaandOlympia•  Upto40secondsoflocalgroundshaking•  ~400injured,1death•  $2+billiondamage

IRIS

h@p://www.dnr.wa.gov

March11,2011ImagineyouareinTokyo,workingonyourcomputer:hXp://www.youtube.com/watch?v=n-FMpNBfna8AndthenyouturnonyourTV:hXp://www.youtube.com/watch?v=w3AdFjklR50

March11,2011

,Kisenumacity,Miyagiprefecture,Japan

Houses were washed away by tsunami in Sendai, Miyagi Prefecture in eastern Japan, after Japan was struck by a magnitude 9.0 earthquake off the northeastern coast. New York Times

The tsunami, seen crashing into homes in Natori, Miyagi prefecture. AP

Part of houses swallowed by tsunami burn in Sendai, Miyagi Prefecture (state) after Japan was struck by a strong earthquake off its northeastern coast Friday, March 11, 2011. New York Times

TsunamihijngSendaiairport

Post-tsunami

FukushimaDaiichinuclearpowerstaAondailymail.co.uk

2011TohokuEarthquake(NEJapan)Friday,March11,2011at2:46PMlocalAmeMagnitude9.0–fourthlargestsince1900Generatedpowerfultsunamiupto40metershigh

•  swept>10kminland(Sendaiplain)•  inundatedarea>550km2

15,894deaths+2,572missingpersons+1,600evacuaAondeaths300,000evacuees(230,000sAlldisplaced)125,000+buildingsdestroyed;onemilliondamagedEst.economiccost(WorldBank)=US$235billionReal-AmeearthquakewarningissuedFukushimaDaiichinuclearpowerplant–heavilydamaged,parAal

meltdowns,radioacAvityrelease,clean-upongoingJapan–historyofdevastaAngearthquakes,tsunamis

-1923GreatKantoEQ,M7.9,143,000deaths-excellentbuildingcodes,seismicmonitoring,plans,etc.

Approximate Rupture Zone

USGS

InferreddistribuAonofslipforthegreat11March2011TohokuEarthquakebasedoninverAngfourdifferentdatasets(Yokotaetal.,2011)

Simonsetal.(2011)

Pre-EQGPS

AserEQ

W E EW

Cascadia

NortheastJapanW E EW

hXp://eqseis.geosc.psu.edu/~cammon/Japan2011EQ/

Red=mainshocksandasershocksof11March2011earthquake

HeadquartersforEarthquakeResearchPromoAon

2011TohokuEarthquake(NEJapan)Earlyalertsystemsavedmanythousandsoflives

80bullettrainsstoppedsafely98%TVstaConsbroadcastalerts52millioncellphonealerts

BUT-thesizeoftheearthquakeandthetsunamiweresignificantlyunderesCmated,bothpriortotheearthquakeandinrealCmealertsmessages.LackofindependentoversightandregulaConofJapanesenuclearpowerindustry

hNp://www.youtube.com/watch?feature=player_embedded&v=xYctjv7ouBc

P-waves(~6.4km/s)travelfasterthantheS-waves(~3.7km/s)andsurfacewavesthatcausegroundshaking.Electronstravelwayfasterthanseismicwaves!

LivecoverageofJapanparliamentarysessioninTokyo,370kmfromepicenter

Notes Update number

Time since first P-wave

detection (sec)

Estimated magnitude

Estimated maximum shaking

intensity (JMA scale)

Lat Lon Depth (km)

Origin time

1st assessment of the event, 5.4 sec after 1st P-wave

detection

1 5.4 4.3 1 38.2 142.7 10 14:46:19

2 6.5 5.9 3 38.2 142.7 10 14:46:19

3 7.5 6.8 4 38.2 142.7 10 14:46:19

Earthquake warning issued 4 8.6 7.2 5-lower 38.2 142.7 10 14:46:19

5 9.6 6.3 4 38.2 142.7 10 14:46:19

6 10.7 6.6 4 38.2 142.7 10 14:46:19

7 11.0 6.6 4 38.2 142.7 10 14:46:19

8 15.9 7.2 4 38.1 142.9 10 14:46:17

9 22.2 7.6 5-lower 38.1 142.9 10 14:46:16

10 30.0 7.7 5-lower 38.1 142.9 10 14:46:16

11 45.0 7.7 5-lower 38.1 142.9 10 14:46:16

12 65.1 7.9 5-upper 38.1 142.9 10 14:46:17

13 85.0 8.0 5-upper 38.1 142.9 10 14:46:17

14 105.0 8.1 6-lower 38.1 142.9 10 14:46:17

15 116.8 8.1 6-lower 38.1 142.9 10 14:46:17

Table notes. The first P-wave detection was at 14:46:40.2. All times are JST on March 11, 2011.

hNp://seismo.berkeley.edu/~rallen/research/WarningsInJapan/

Oct2007–JapanturnedonfirstpublicnaConalearthquakewarningsystemOperatedbytheJapanMeteorologicalAgency(JMA)

Mar2011–firsttruetest

Yokotaetal.(2011)

Tsunamiwaveheights,11March2011TohokuEarthquake

MeasuredtsunamiheightsresulCngfrom11March2011Earthquake.JapanSocietyofCivilEngineersTohokuEarthquakeTsunamiInformaCon,hNp://www.coastal.jp/tsunami2011/index.php

“Ahouseonahighlandbringspeaceandhappinesstoyourchildrenandgrandchildren-Remembertheravagesofthegreattsunami-Donotbuildanyhousesbelowthispoint”

(translaCon,H.Takagi,WasedaU;Photo–M.Oishi)

GrandtsunamimonumentinAneyoshi,Miyako

Builtaperthe13July869ADSanriku(Jōgan)EarthquakeEsCmatedmag=8.3+(Minouraetal.,2002)Tsunamireached38.9metersabovesealevel

IRIS

Hyndman(1995)

WehavenowriNenhistoricalrecordofpastmagnitude9CascadiaearthquakesButoralhistoriesofaboriginalgroupsinthePacificNorthwesttellofenCrevillagesdevastatedbyviolentgroundshakingandmassivefloods

Chief Louis Nookmiis (1880-1964)

“This is the most important story the Huu-ay-aht people have”

AwallofwateresCmatedatover50feetsweptthroughAnaclaandothercoastalvillagesdrowningthousandsofNuu-chah-nulth-aht

DrownedCoastalForests-Cascadia

BrianAtwaterU.S.GeologicalSurvey

AtwaterandHemphill-Haley(1997)

9PM,Jan26,1700ADbasedonJapanesetsunamirecord!

124 Turbidite Event History—Methods and Implications for Holocene Paleoseismicity of the Cascadia Subduction Zone

05001,0001,5002,0002,5003,0003,5004,0004,5005,0005,5006,0006,5007,0007,5008,0008,5009,0009,500

Turb

idite

mas

s (s

cale

d)

0

200

400

600

800

1,000

T1

T2T3

T4T5T6

T7

T8

T9

T10

T11

T12

T13

T14T15

T16

T17

T17a

T18

cluster avg. = 330 yr(150–510)

clusterclusterclustercluster avg. = 560 yr

(340–740)cluster avg. = 510 yr

(330–690)

cluster

Gap 980

(800–1,130)years

Gap 1190

(1,020–1,380) years

cluster

Gap720

(570–870)years

Gap730

(540–910)years

cluster avg. = 500 yr(320–580)

cluster avg. = 300 yr(120–480)

A

B

C

Calibrated years B.P. (1950)

05001,0001,5002,0002,5003,0003,5004,0004,5005,0005,5006,0006,5007,0007,5008,0008,5009,0009,50010,000

Turb

idite

mas

s (s

cale

d)

0

200

400

600

800

1,000

T1

T2T3

T4T5T6

T7

T8

T9

T10

T11

T12

T13

T14T15

T16

T17

T17a

T18

cluster avg. = 330 yr(150–510)

clusterclusterclustercluster avg. = 560 yr

(340–740)

clustercluster avg. = 550 yr

(370–730)cluster avg. = 300 yr

(120–480)

3.00

2.25

1.50

0.75

0.00

Diss

imila

rity

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 17a18

DendrogramVariables C2 Clustering method: Complete linkage (furthest neighbor) Distance type: Euclidean Scale type: Standard deviation

Cophenetic correlation: 0.809855 Delta(0.5): 0.393080 Delta(1.0): 0.445 917

Event number

Gap 980

(800–1,130)years

Gap 1,190

(1,020–1,380) years

Gap730

(540–910)years

Cluster 1 Cluster 2 Cluster 3 Cluster 4

Figure 60. A, Time series of Cascadia turbidite emplacement for the northern and

central Cascadia margin. Bars are scaled with height representing turbidite mass (taller bars are larger turbidites).

Bar widths are the 2V�error range from OxCal combines for each event. Turbidite mass is calculated from gamma density data for

cores M9907-12PC (Juan de Fuca Channel) and M9907-23PC (Cascadia Channel) (data given in table 12). The time series suggests a history of clusters of earthquakes (average repeat times shown) separated by gaps of ~750–1,150 years. Gaps appear to have a tendency to conclude with a large event. B, Four cluster models. C, Clustering dendrogram for the north-central Cascadia turbidite time series, model B.

Goldfingeretal.(2012)

ChrisGoldfinger(OregonStateUniv)BasedonoffshoresubmarinelandsliderecordNineteengreatmagnitude~9earthquakesin

thelast10,000yearsAveragerecurrenceinterval~500-530yearsRecurrenceintervalrangesfrom200to800

years,possibleclustersseparatedbygaps

Earthquakerecordlast10,000years

USGSM9.0planningscenariofromCREW(2103)

ModifiedMercalliIntensityScaleVII“VeryStrong”PerceivedShaking“Moderate”PotenRalDamage

DamagenegligibleinbuildingsofgooddesignandconstrucRon;slighttomoderateinwell-builtordinarystructures;considerabledamageinpoorlybuiltorbadlydesignedstructures;somechimneysbroken.

TimesColonist

Essen:alinfrastructurewillbeheavilydamagedbygroundshaking,rockslides

•  TransportaRonnetworks:

-bridges,roads,railways•  Airports•  Ports,shippingchannels•  Electricity,naturalgas,liquidfuels•  Watersystems–firefighRng,drinking•  CommunicaRonnetworks•  CriRcalfaciliRes-hospitals,firestaRons

CascadiaRegionEarthquakeGroup,

2013www.crew.org

Tsunamiwillinundatelow-lyingareasalongthewestcoastofVancouverIsland,Washington,Oregon,Calif

Tsunami from Cascadia subduction zone

Clagueetal.(2006)

LiquefacRon

GeomapVancouver

Groundshakingdependsonearthquakemagnitude,distancefromepicenterandlocalgeologyUnconsolidatedsoil(muds,sands)àamplifiedshakingandliquefacRon:

-Richmond,Delta-FalseCreek

Geology

GroundShakinginVancouvercausedbyMagnitude9CascadiaEarthquake

Expect3to4minutesofverystronglateralshaking,withmanyaOershocksoccurringformonthsaOerwardWhatwillhappentomyhomeorworkplaceduringanearthquake?

Whenwasthebuildingbuilt? FirstcomprehensiveseismicbuildingcodeinCanada-1953 Majorupgradestoseismicbuildingcodesin1970,1985,2005 OurseismiccodesconRnuetobestrengthenedaswelearnmoreWhereisbuildinglocated? Loosesoil–moreshakingWhatisthebuildingmadeof? Unreinforcedconcreteorbrickbuildingsperformpoorly Woodframehomesshouldperformwell(exceptchimneysandglass)Howlongandhowviolentlydoesthegroundshake?

Journeayetal.(2015)AprofileofearthquakeriskfortheDistrictofNorthVancouver,BriCshColumbia.Geol.Surv.CanadaOpenFile7677

EsCmatedgroundmoConsProbabilisCc DeterminisCc

Riversands,gravel

Sandstone

Glacialsands,gravel,clay

Landfill

Granites

GeologicalSurveyCanada(1998)GeoScape

Journeayetal.(2015)GroundShakingHazard

Deeporange=severeshaking,PGA=29-55%g,PGV=30-60cm/s

1.Planandprepare

AssessandreduceriskEmergencymanagementplanning,pracCse“TheworstAmetobeexchangingbusinesscardsisduringacrisis.”-MarciaMcNuG

Hardeninfrastructure

StrictbuildingcodesRetrofitorrebuildcriCcalinfrastructure Hospitals,firestaCons Bridges(disasterrelief) AirportSteadyinvestmentinallpublicbuildings Schools,communitycentres,…

Develop,deployearlywarningsystemsEducatepublicàpersonalpreparaCon

Secureyourhome,communicaConplan,disastersupplies NextShakeoutBC–October20,2016

BriCshColumbiagovernmenthGp://www2.gov.bc.ca

2.Survive

DROPdownontoyourhandsandkneesGetundersturdydeskortableCrouchagainstinteriorwallTriangleoflife–no!Doorway–no!

COVERyourheadandneckHOLDONWaitunClshakingstopstogetoutTurnoffgas,waterWestcoasttsunami–seekhighground

3.RespondandrecoverSearchandrescueHelptheinjured,gethospitalsfuncConingReliefsupplies

GetairportandhighwaysopenRestoreessenCalservices

Water,electricity,sewerTelecommunicaCons

DebrisremovalGetourcityupandrunning

ReconnectandrebuildourcommuniCesMinimizeeconomicdisrupCon

NextShakeoutBC–October20,2016

WealthofinformaCononthewebonhowtobestprepareforanearthquake:

Resources

GovernmentofCanada-hGp://www.getprepared.gc.caGovernmentofBriHshColumbia-hGp://www2.gov.bc.ca/gov/content/safety/emergency-preparedness-response-recovery/preparedbc/know-the-risks/earthquakesShakeoutBC–www.shakeoutbc.canextBCwideeventOctober20,2016CityofVancouver-hGp://vancouver.ca/home-property-development/earthquake.aspxUBC-hGp://riskmanagement.ubc.ca/emergency-mgt/emergency-procedures/earthquakeCascadiaRegionEarthquakeWorkgroup-www.crew.org

TheEnd