the great sumatra earthquake and indian ocean tsunami...

Earthquake EngineeringEarthquake Engineering

Research InstituteResearch Institute

An illustrated description of their causes and effects

The Great Sumatra Earthquake and The Great Sumatra Earthquake and

Indian Ocean Tsunami Indian Ocean Tsunami

of December 26, 2004of December 26, 2004

This presentation was developed to explain the origins of the This presentation was developed to explain the origins of the Sumatra earthquake of December 26, 2004 and the ensuing Sumatra earthquake of December 26, 2004 and the ensuing tsunami, and to document the damages caused by the tsunami, and to document the damages caused by the earthquake and tsunami in so many countries around the earthquake and tsunami in so many countries around the Indian Ocean.Indian Ocean.

This project was supported by funds from the National Science FoThis project was supported by funds from the National Science Foundation through undation through

EERIEERI’’ss Learning From Earthquakes Program under grant # CMSLearning From Earthquakes Program under grant # CMS--01318950131895

�� The presentation was created The presentation was created largely by largely by WidiantoWidianto, a doctoral , a doctoral candidate in civil engineering candidate in civil engineering and president of the EERI and president of the EERI student chapter at the student chapter at the University of Texas at Austin. University of Texas at Austin.

�� Other contributors include Other contributors include Sarah Nathe, Craig Comartin, Sarah Nathe, Craig Comartin, and Heidi Faison.and Heidi Faison.

PrefacePreface

United States Geological Survey (USGS)

“The tsunami that struck Southeast Asia on

December 26, 2004 has been confirmed as the most

devastating in modern history.”

Guinness Book of World Records

“The 26th December 2004 Sumatra-Andaman

earthquake is the fourth largest earthquake in the

world since 1900 and is the largest since the 1964

Prince William Sound, Alaska earthquake.”

Contents� Introduction: Plate tectonics, earthquakes

� Sumatra Earthquake

- Tectonic activity

- Observations

- Damage

� Indian Ocean Tsunami

- Basic mechanism

- Videos: before and after giant wave arrival

- Damage

� Tsunamis in the USA

� Tsunami Risk Reduction

� The Earthquake Engineering Research Institute

Introduction – Plate Tectonics� The Earth is characterized by a small number of lithospheric plates that

float on a viscous underlayer called the asthenosphere.

� Geological evidence shows that plates undergo constant, gradual

change. Magma is continually upwelling at the mid-oceanic ridges and rises

as the seafloor spreads apart.

� In some areas, large sections of plates are forced to move beneath other

plates (surface layers of rocks are absorbed into the earth’s interior). These

areas are called subduction zones.

�� A plate being subducted beneath another

Introduction – Plate Tectonics

Source: Earthquakes by Bruce A. Bolt

Introduction – Plate Tectonics

95% of earthquakes occur along the edges of the interacting plates


World’s Largest Magnitude Earthquakes

Approx. casualtiesApprox. casualtiesYearYearMagnitudeMagnitudeEarthquakeEarthquake

>283,100 >283,100

(>173,000 in Indonesia)(>173,000 in Indonesia)

200420049.09.05. Sumatra5. Sumatra

Not reportedNot reported195219529.09.04.4. KamchatkaKamchatka

PeninsulaPeninsula

Not reportedNot reported195719579.19.13.3. AndreanofAndreanof

Islands, AlaskaIslands, Alaska

≅≅≅≅≅≅≅≅ 125125196419649.29.22. Prince William 2. Prince William

Sound, AlaskaSound, Alaska

>2000>2000196019609.59.51. Chile1. Chile

Source: United States Geological Survey (USGS)

Earthquake Energy


Sumatra-Andaman (2004)

Sumatra Earthquake

Magnitude: 9.0

Date-time: Sunday, December 26,

2004 at 7:58:53 AM (local time)

Depth: 30 km (18.6 miles)

Distances:

* 250 km (155 miles) SSE of Aceh,

Sumatra, Indonesia

* 310 km (195 miles) W of Medan,

Sumatra, Indonesia

* 1260 km (780 miles) SSW of

Bangkok, Thailand

* 1605 km (990 miles) NW of

Jakarta, Java, Indonesia


Tectonic Summary

� It occurred on the interface of

the India and Burma plates: an

interplate earthquake.

� India plate subducts beneath

the overriding Burma plate at

the Sunda Trench.

� In the region of the earthquake,

the India plate moves toward the

northeast at a rate of about

6 cm/year relative to the Burma

plate.

� Thrust faulting caused the

earthquake (slip directed

perpendicular to the trench).

� Fault rupture propagated to

the northwest from the epicenter

with a width ≅ 100 km and an

average displacement on the fault

plane ≅ 20 meters.

6 cm/yr


Felt Shaking Reports�Modified Mercalli Intensity Scale:

� Banda Aceh, Sumatra: IX

� Medan, Sumatra: IV

� Port Blair, Andaman Islands: VII

� Subsidence and landslides

were observed in Sumatra.

� A mud volcano near Baratang,

Andaman Islands began erupting

on December 28, 2004.

� Intensity vs. Distance from

Epicenter Plot :


AftershockAftershock

ZoneZone

� Extends from

Northern Sumatra to

the Andaman Islands,

~ 1300 km to the north.

� Largest aftershock

directly following the

main shock was M =

7.1 in the Nicobar

Islands.

�On March 28, 2005, a

M = 8.7 earthquake

occurred in a region of

the fault southeast of

the Dec 26th mainshock

and its rupture zone.

Epicenter of mainshock,

28 Mar 2005

Earthquake Damage Earthquake Damage

Structural damage to concrete frame building.

epicenter

Banda Aceh

epicenter

Banda Aceh

Location: Banda Aceh,

Sumatra, Indonesia

Photo: Jose Borrero

Earthquake DamageEarthquake Damage

Partial collapse of concrete frame building due to column failure.

epicenter

Banda Aceh

epicenter

Banda Aceh


Sumatra, Indonesia

Photo: Murat Saatcioglu, Ahmed

Ghobarah, Ioan Nistor

Partial collapse of concrete frame building due inadequate column reinforcement.

epicenter

Banda Aceh

epicenter

Banda Aceh

Location: Banda Aceh

Sumatra, Indonesia

Photos: Murat Saatcioglu, Ahmed

Ghobarah, Ioan Nistor

Earthquake DamageEarthquake Damage


Architectural damage to the

Grand Mosque tower.

epicenter

Banda Aceh

epicenter

Banda Aceh


Sumatra, Indonesia

Photo: Jose Borrero


Source: Geological Survey of India

Location: Port Blair,

Andaman Islands

epicenter

Port Blair

epicenter

Port Blair

Column of residential building damaged by ground motion.



Location: Port Blair,

Andaman Islands

epicenter

Port Blair

epicenter

Port Blair

Longitudinal (50 m long)

crack on Kamraj Road after

the earthquake

Major crack showing a rupture width of

15 cm on Kamraj Road after the

earthquake

Earthquake and Tsunami

Not all earthquakes generate tsunamis.

An earthquake must have certain characteristics in order to

generate a tsunami:


1. Epicenter is underneath or near the ocean.

2. Fault causes vertical movement of the sea floor (up to

several meters) over a large area (up to 100,000 km2).

3. Large magnitude ( > 7.5 ) AND shallow focus ( < 70 km).

Basic Tsunami Mechanism

� An earthquake causes a

vertical movement of the

seafloor, which displaces the

sea water.

� Large waves then

radiate from the epicenter

in all directions.

Tsunami Explained� A tsunami is series of traveling ocean waves of extremely long length

generated primarily by earthquakes occurring below or near the ocean floor.

� Tsunami waves propagate across the deep ocean with a speed exceeding

800 km/h (≅ 500 mph) and a wave height of only a few tens of centimeters or

less.

� As they reach the shallow waters of the coast, the waves slow down and

their height increases up to tens of meters (30 ft) or more.

Source: NOAA

Tsunami Translated

� “Tidal wave” is a misnomer because the cause

is unrelated to tides.

� “Seismic sea wave” is misleading because a

tsunami can be caused by non-seismic events,

and it is not dangerous in the open ocean.

Japanese word:

“Tsu“ means

“harbor”

“Nami“ means

“wave”

English translation:

“Harbor wave”

Water Recession: A Precursor

From: Nature Publishing GroupFrom: Nature Publishing Group

Wave Generation Draw Down Effect

From: Digital Globe

Kalutara Beach, Sri Lanka

Tsunami Wave AppearanceTsunami Wave Appearance

�� A tsunami wave crest has A tsunami wave crest has three general appearances three general appearances from shore:from shore:�� FastFast--rising tiderising tide

�� Cresting waveCresting wave

�� A stepA step--like change in the like change in the water level that advances water level that advances rapidly (called a rapidly (called a borebore))

�� Series of wavesSeries of waves�� Most tsunamis come in a series of waves that may last for severaMost tsunamis come in a series of waves that may last for severall

hourshours

�� The outflow of water back to the sea between waves can cause The outflow of water back to the sea between waves can cause more damage than the original incoming wave frontsmore damage than the original incoming wave fronts

�� The first wave is rarely the largestThe first wave is rarely the largest

A bore on the Qian Tang Jiang River, China

Source: www.waveofdestruction.org

Tsunami Propagation

National Institute of Advanced Industrial Science and Technology, Japan

Tsunami Damage Tsunami Damage

Before Tsunami

January 10, 2003

After Tsunami

December 29, 2004

Source: National University of Singapore

Location: Lhoknga, Indonesia

epicenter

Lhoknga

epicenter

Lhoknga

Tsunami DamageTsunami DamageLocation: Lhoknga, Indonesia

epicenter

Lhoknga

epicenter

Lhoknga

Exposed

bridge piers of

road that

washed away.

Damage zone showing an

overturned tanker, trees

snapped in half, and the

high water mark on islands

where vegetation was

stripped away.

Overturned

ship

High Water Mark

Broken Trees

Photo: Jose Borrero

Photo: Jose Borrero


Before Tsunami

April 12, 2004

After Tsunami

January 2, 2005

Source: Digital Globe

Location: Gleebruk, Indonesia

epicenter

Gleebruk

epicenter

Gleebruk


Before Tsunami

April 12, 2004

After Tsunami

January 2, 2005


epicenter

Gleebruk

epicenter

Gleebruk


Before Tsunami

June 23, 2004

After Tsunami

December 28, 2004


Location: Banda Aceh, Indonesia

epicenter

Banda Aceh

epicenter

Banda Aceh

Tsunami DamageTsunami DamageLocation: Banda Aceh, Indonesia

epicenter

Banda Aceh

epicenter

Banda Aceh

Damage was caused by

both water and water-borne

debris.

A boat was

lifted on top

of houses

by the

waves.

Photo: Jose Borrero

Photo: Jose Borrero

Tsunami DamageTsunami Damage

Location: Banda Aceh & Lhoknga,

Indonesia

epicenter

Banda Aceh

epicenter

Banda Aceh

The tsunami waves came

from many directions and

flowed across the tip of

northeastern Sumatra.

Graphic: Jose Borrero

epicenter

Kerala Coast

epicenter

Kerala Coast


Location: Thailand

Damage to Kao

Lak Resort from

tsunami waves.

Despite the presence of debris,

this naval base building had

little structural damage due to a

retaining wall at its frontage.

Photo: Curt Edwards

Photo: Chitr Lilavivat

Thailand


Location: Sri Lanka

epicenter

Kerala Coast

epicenter

Kerala CoastSri Lanka

Damage to house in Tangala.

Flow depths were

about 4.5 m at Yala

Safari Resort, where

water levels were

determined by debris

in the trees (see door

impaled on branch).


Location: Kerala, India


epicenter

Kerala Coast

epicenter

Kerala Coast

The collapsed front

portion of a concrete

house.

In the village of Alappad, the foundations and

the soil beneath many of the houses were

scoured out.

Tsunamis in the U.S.A.Tsunamis in the U.S.A.�� TheThe west coastwest coast, from California to Alaska, is vulnerable to , from California to Alaska, is vulnerable to

tsunamis from nearby or distant earthquakes. tsunamis from nearby or distant earthquakes.

�� HawaiiHawaii is extremely vulnerable to all tsunamis in the Pacific is extremely vulnerable to all tsunamis in the Pacific Ocean.Ocean.

�� California, Oregon, Washington, Alaska and Hawaii all have California, Oregon, Washington, Alaska and Hawaii all have tsunami education programstsunami education programs for residents and visitors, for residents and visitors, coastal signagecoastal signage, and , and warning response planswarning response plans..

Photo: Eugene Schader, NISEE Collection

Warped pier in Crescent City, CA caused by

1964 Alaska earthquake tsunami

Photo: Kirkpatrick, NISEE Collection

Tsunami induced damage in Seward, Alaska

from 1964 Alaska earthquake

Historical Tsunamis in the U.S.A.Historical Tsunamis in the U.S.A.

unknownunknownWest coast West coast 17001700CascadiaCascadia FaultFault

EarthquakeEarthquake

Tsunami CasualtiesTsunami CasualtiesAffected StatesAffected StatesYearYearTsunami SourceTsunami Source

120120 (total)(total)AK, HI , WA, CAAK, HI , WA, CA19641964Alaska EarthquakeAlaska Earthquake

(Mw = 9.3)(Mw = 9.3)

6161 (Hilo, Hawaii)(Hilo, Hawaii)CA, HICA, HI19601960Chile EarthquakeChile Earthquake

(Mw = 9.5)(Mw = 9.5)

22AKAK19581958LituyaLituya Bay, AlaskaBay, Alaska

LandslideLandslide

159 (Hilo, Hawaii)159 (Hilo, Hawaii)

165165 (total)(total)

AK, HI , WA, OR, CAAK, HI , WA, OR, CA19461946Aleutian EarthquakeAleutian Earthquake

(Mw = 8.3)(Mw = 8.3)

Sources: NOVA; International Tsunami Information Center (ITIC)

Tsunami Risk ReductionTsunami Risk Reduction

1.1. Determine & understand community tsunami riskDetermine & understand community tsunami risk�� Hazard: Hazard:

� Study the shape of the sea floor and the coastal topography

� Run simulations of tsunamis

�� Vulnerability:Vulnerability:

�� DevelopDevelop mapsmaps of potential risk areas of potential risk areas

�� Exposure:Exposure:

�� Costal communities, especially with tsunami historyCostal communities, especially with tsunami history

2.2. Avoid new development in tsunami runAvoid new development in tsunami run--up areasup areas

1.1. Designate risk areas as Designate risk areas as openopen--spacespace, i.e., parks and agriculture, i.e., parks and agriculture

2.2. Zone to minimize human riskZone to minimize human risk

1.1. Low density residential zoningLow density residential zoning

2.2. Large singleLarge single--residence lotsresidence lots


3.3. Locate and configure new development in the runLocate and configure new development in the run--upup

areas to minimize future tsunami lossesareas to minimize future tsunami losses

� Avoid inundation areas

i.e. build on high ground

� Slowing water currents

i.e. Conserve or replant coastal belts

of forest and mangrove swamps

� Steering water forces

i.e. angled, by-pass walls

� Blocking water forces

i.e. Build sea walls

SLOWING

STEERING

BLOCKINGSource: National Tsunami Hazard Mitigation Program (NTHMP)


Elevated restaurant in Hilo, Hawaii. Lower level is designed

to allow waves to pass through.

Source: National Tsunami Hazard Mitigation Program

4.4. Design and construct new buildings to minimize Design and construct new buildings to minimize tsunami damagetsunami damage

� Heavy and rigid structure

� Raise building on stilts*

� Many openings on the

ground floor *

� Orient perpendicular to the

shoreline:

*Use caution with this design in areas

with high earthquake-shaking risk.


WAVE

Overturning

Sliding

Scouring

Buoyancy

Water pressure

& debris impact

WAVE

Overturning

Sliding

Scouring

Buoyancy

Water pressure

& debris impact

4. Tsunami-resistant buildings (cont.)

Tsunami forces on

structures

Lowest

horizontal

structure

above wave-

crest

Horizontal

member

perpendicular to

the wave

Lateral bracing

Deep protected piles

Rigid connection

Lowest

horizontal

structure

above wave-

crest

Horizontal

member

perpendicular to

the wave

Lateral bracing

Deep protected piles

Rigid connection

Structure designed to resist

tsunami forces

Source: National Tsunami Hazard Mitigation Program (NTHMP)

Caveat: Remember EarthquakeCaveat: Remember Earthquake--

Resistant Design Principles Resistant Design Principles

�� Most communities at risk from tsunamis are also at risk from Most communities at risk from tsunamis are also at risk from

damaging earthquakesdamaging earthquakes

�� Buildings designed well for earthquakes typically perform Buildings designed well for earthquakes typically perform

well in tsunamiswell in tsunamis

Well-designed building withstood tsunami forces

without collapse in Banda Aceh, Indonesia

Photo: Jose Borrero

Well-designed building standing amidst the

rubble in Banda Aceh, Indonesia

Photo: Jose Borrero


5.5. Protect existing developmentProtect existing development throughthroughredevelopment, retrofit, and land reuse plans and redevelopment, retrofit, and land reuse plans and projectsprojects

6.6. Take special precautions in locating and designing Take special precautions in locating and designing infrastructureinfrastructure andand critical facilitiescritical facilities

� Locate critical infrastructure (water plants, hospitals, etc) outside the tsunami danger zone

�� Relocate or protect critical infrastructureRelocate or protect critical infrastructure

�� Plan for emergency and recovery Plan for emergency and recovery


�� Plan for EvacuationPlan for Evacuation

�� IdentifyIdentify vertical evacuation buildingsvertical evacuation buildings

�� Create horizontal Create horizontal evacuation routesevacuation routes

�� DevelopDevelop early warning systemsearly warning systems

�� EducateEducate and inform publicand inform public

Tsunami Risk Reduction Tsunami Risk Reduction Tsunami early warning system:

� Pressure sensors sit on the ocean

bottom and measure the weight of

water column above them.

� If a tsunami passes overhead, the

pressure increases and the sensor

sends a signal to a buoy sitting on the

sea surface.

� The buoy then sends a signal to a

satellite, which in turn alerts a staffed

early warning center.


The least expensive and the most important mitigation effort is …

"Even without a warning system, even in places where they

didn't feel the earthquake, if people had simply

understood that when you see the water go down, when

you hear a rumble from the coast, you don't go down to

investigate, you grab your babies and run for your life,

many lives would have been saved."

Lori Dengler, Humboldt State UniversityNew Scientist MagazineNew Scientist Magazine

January 15, 2005January 15, 2005

The power of knowledge:The power of knowledge:

�� VictorVictor DesosaDesosa saved the saved the villagevillage ofof GalbokkaGalbokka in Sri in Sri Lanka because Lanka because he knew he knew what to dowhat to do when the water when the water receded.receded.

�� Only one inhabitant in his Only one inhabitant in his village was killed.village was killed.

�� Casualty rates in nearby Casualty rates in nearby villages were 70 villages were 70 –– 90 %90 %

“Natural hazards are inevitable.“Natural hazards are inevitable.

Natural disasters are not.”Natural disasters are not.”

John John FilsonFilson, USGS retired, USGS retired

New York TimesNew York Times

December 27, 2004December 27, 2004

Earthquake EngineeringEarthquake Engineering

Research InstituteResearch Institute

�� EERI is a professional, association dedicated to EERI is a professional, association dedicated to

reducing earthquake risk. reducing earthquake risk.

�� Members of EERI work in the many different Members of EERI work in the many different

fields of research and professional practice fields of research and professional practice

dedicated to reducing earthquake losses. dedicated to reducing earthquake losses.

EERI ProgramsEERI Programs

�� PublicationsPublications –– Website, Monthly Newsletter and Website, Monthly Newsletter and

Quarterly Technical JournalQuarterly Technical Journal----Earthquake SpectraEarthquake Spectra

�� TechnicalTechnical SeminarsSeminars & National & National ConferencesConferences

�� Web based Web based World Housing EncyclopediaWorld Housing Encyclopedia

�� 55 Regional ChaptersRegional Chapters ---- Political AdvocacyPolitical Advocacy

�� 2020 Student ChaptersStudent Chapters

�� Learning From Earthquakes ProgramLearning From Earthquakes Program

Field reconnaissanceField reconnaissance of earthquake impacts to learn of earthquake impacts to learn

lessons for research and practicelessons for research and practice

To contact us or become a member of EERI, visit our website: To contact us or become a member of EERI, visit our website:

www.eeri.orgwww.eeri.org

ReferencesReferences� United States Geological Survey (USGS)

� U.S. National Oceanic and Atmospheric Administration (NOAA)

� UNESCO / Intergovernmental Oceanographic Commission (IOC)

� International Tsunami Information Center (ITIC)

� Laboratoire de Geophysique, France (LDG)

� Earthquakes: A Primer, Bruce A . Bolt, W.H. Freeman, 1978

� Digital Globe

� Geological Survey of India

� National University of Singapore

� New Scientist magazine, Issue #2482, January 15, 2005

� BBC News

� Nature, Vol. 433, January 27, 2005, Nature Publishing Group

� Sri Lanka Reconnaissance Teams: http://walrus.wr.usgs.gov/tsunami/srilanka05/ &

http://www.gtsav.gatech.edu/cee/groups/tsunami/index.html

ReferencesReferences (cont.)(cont.)

� Natural Tsunami Hazard Mitigation Program (NTHMP), Designing for

Tsunamis, March 2001

� National Information Service for Earthquake Engineering (NISEE),

Earthquake Image Database, Karl Steinbrugge Collection

� www.wavesofdestruction.org

� “Field Survey of Northern Sumatra,” Jose Borrero, EERI Newsletter,

March 2005

� Pacific Tsunami Museum

� NOVA: “The Wave that Shook the World,” PBS http://www.pbs.org/wgbh/nova/tsunami/

� Metro TV, Surabaya Citra Televisi Indonesia (SCTV), Rajawali Citra

Televisi Indonesia (RCTI)

� Prof. Wiratman Wangsadinata, Wiratman & Associates Consulting

Company, Indonesia

� EERI’s Virtual Clearinghouse: http://www.eeri.org/lfe/clearinghouse/sumatra_tsunami/overview.html

the great sumatra earthquake and indian ocean tsunami...

Documents