U.S. DEPARTMENT OF THE INTERIOR EARTHQUAKE … · KAWAGUCHI Nakaminato MATSUSHIRO NAGANOHARA...

137 138 139 140 141 142 143

137 138 139 140 141 142 143

36

37

38

39

40

36

37

38

39

40

Epicentral Area

S E A O F J A P A N

P A C I F I CO C E A N

Sado

Awa Shima

Tobi Shima

ToyamaWan

IshinomakiWan

SENDAISENDAI

H O N S H U

19231921

1924

19821965

1938

1938

1938

1938

1938

19381908

1905

1959

1927

1962

19781933 1915

193619371964

19001981

1915

19141968

19281939

1989

SUWA

KOGA

MITO

UEDA

KUJI

UOZUUEDA

Kamo

MAKI

Tono

KADO

OKAYO

HONJO

OYAMA

KIRYU

ASHIO

NikkoDAIGO

UNAMI

TAIRA

KOIDE

Ojiya

NAMIEOtani

SANJO

Gosen

CHIDA

Kaita

OguniNagai

TENDOSagae

INNAI

Honjo

AKITA

OMOTO

KONOSUAidara

TAKANO HOKOTA

KUROGO

Kasama

Omachi

NumataSUZAKANAGANO

TOYAMA

Liyama

YuzawaTOMARI

TAKADA

TAJIMA

Odaira

NOZAWA

NIITSU

KAMEDA

WATARI

Ryotsu

SENDAI

Takaki

WAKUYA

MINATOShinjo

SAKATA

FUKURA

Yokote

YAMADA

HIZUME

MIYAKOWainai

MONZEN

Ishioka

TomiokaISEZAKI

FUNATSU

TOCHIGI

HITACHI

Imaichi

TAKAOKA Isohara

OtawaraONAHAMA

KuroisoMITSUYA

NAOETSU

Kammata

NAGAOKA

NIIGATA SHIBATA

Ofunata

YASHIMA

Omagari

Akasawa

MORIOKA

HITOCHI

TAKAYAWA KUMAGAYA

FURUKAWATAKASAKI

MAEBASHI

Itoigawa

TOKAMCHI Ishikawa

KORIYAMA

KAWAGETA

NAKUMURA

YONEZAWA

MurakamiYAMAGATA

SHIOGAMA

WATANOHAWakikawa YOSHIOKA

FURUKAWA

IWAEYAMA

TSURUOKA

SURISAWA

MIZUSAWA

KAMAISHI

HANAMAKI

KARLWANO

Tamagawa

MATSUYAMA Hamatsuga

MATSUMOTO

SHIMODATETsunogawa KARUIZAWA

ShibukawaUTSUNMIYA

Hinoemata

Shirakawa

MATSUNAMI

WAKAMATSU

IZUMOZAKI

Haramachi

FUKUSAIMA

Obanazawa

KESENNUMA

Shirahama

KAWAGUCHI

Nakaminato

NAGANOHARAMATSUSHIRO

KARASUYAMA

Nihommatsu

Teradomari

SHIMO-SEKI

ISHINOMAKI

ICHINOSEKI

Higashidate

KASHIWAZAKI

SHIZUKUISHI

Higashi-inolani

Zao

Nasu

Asama

Akagi

Shiga

Myoko

Azuma

Iwate

Kanpu

Haruna

NantaiHiuchi

Bandai

Narugo

Chokai

Hijiori

Norikura

Takahara

Numazawa

Kurikoma

Tateshina

Yake-dake

Tate-yama

Hachimantai

Omanago GroupNikko-Shirane

Akita-Yake-yama

Niigata-Yake-yama

Akita-Komaga-take

Washiba-Kumonotaira

1915

1901

Megata

Adatara

Kusatsu-Shirane

Map prepared by U.S. Geological SurveyNational Earthquake Information Center26 October 2003Map not approved for release by Director USGS

EARTHQUAKE SUMMARY MAP XXXU.S. DEPARTMENT OF THE INTERIORU.S. GEOLOGICAL SURVEY

M6.6 Honshu, Japan Earthquake of 23 October 2004

125 130 135 140

145

125 130 135 140

145

25

30

35

40

45

25

30

35

40

45

Tectonic Setting

SOUTHKOREA

NORTHKOREA

RUSS

IAC H I N A

J A P A N

P A C I F I CO C E A N

S E A O F J A P A N

E A S TC H I N A

S E A

P H I L I P P I N ES E A

HONSHU

HOKKAIDO

KYUSHUSHIKOKU

R y u k

y u I

s l a

n d

s

I z u I s l a n d sB

o n i n I s l a n d s

S E A O FO K H O T S K

DETAILED MAP

P A C I F I CP L A T E

P H I L I P P I N EP L A T E

A M U RP L A T E

TOKYOTOKYO

R y u k

y u

T r

e n

c h

Kuril

Tr

ench

J a

p a

n T

r e

n c

h

I z u T r e n c h

B o n i n T

r e n c h

S o

u t h H o n s h u R

i d g e

YellowSea

SAPPOROSAPPORO

SEOULSEOUL

PYONGYANGPYONGYANG

83 mm/yr

O K H O T S KP L A T E

125 130 135 140

145

125 130 135 140

145

25

30

35

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45

25

30

35

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45

Seismicity 1900 - 2002

SOUTHKOREA

NORTHKOREA

RUSS

IAC H I N A

J A P A N

P A C I F I CO C E A N

S E A O F J A P A N

E A S TC H I N A

S E A

P H I L I P P I N ES E A

HONSHU

HOKKAIDO

KYUSHUSHIKOKU

R y u k

y u I

s l a

n d

s

I z u I s l a n d sB

o n i n I s l a n d s

S E A O FO K H O T S K

DETAILED MAP

P A C I F I CP L A T E

P H I L I P P I N EP L A T E

A M U RP L A T E

TOKYOTOKYO

YellowSea

SAPPOROSAPPORO

SEOULSEOUL

PYONGYANGPYONGYANG

O K H O T S KP L A T E

A1

A2

A3

A1'

A2'

A3'

EXPLANATION

Main Shock

23 October 2004

Depth Classes

0 - 69 km

70 - 299

300 - 700

Magnitude Classes

5.00 - 5.49

5.50 - 5.99

6.00 - 6.49

6.50 - 6.99

7.00 - 7.49

7.50 - 8.00

Plate Boundary

Continental Convergent

Continental Rift

Continental LL Transform

Continental RL Transform

Oceanic Convergent

Oceanic Spreading

Oceanic LL Transform

Oceanic RL Transform

Subduction

Volcano

0 100 200 300 40050

Kilometers

SCALE 1:15,000,000Albers Equal-Area Projection

0 100 200 300 40050

Kilometers

SCALE 1:15,000,000Albers Equal-Area Projection

DISCUSSION

The islands of Japan lie on a ring of seismically active plate boundaries that surround the Pacific Ocean known as the Ring of Fire. Earthquakes throughout Japan are caused by the relative motion of several major and minor tectonic plates, including the Pacific plate, the Philippine Sea plate, the Okhotsk plate, and the Amur plate. Earthquakes result from slippage on the interface between the plates and on faults at some distance from the plates' boundaries. The 23 October 2004 earthquake had a thrust fault mech-anism and occurred within the Okhotsk plate, about 350 km west of the Japan Trench, where the Pacific plate subducts beneath the over-riding Okhotsk plate. Within the past 30 years, there have been several significant earthquakes in the vicinity of this earthquake, including a June 1964 magnitude 7.4 earthquake(about 125 km to the north) that killed 36 people and an April 1995 magnitude 5.4 shock (about 90 km to the north) that injured at at least 39 people. During the 20th century, Japan suffered nine devastating earthquakes that killed more than 1000 people each. These include the 1923 magnitude 7.9 earthquake that triggered the great Tokyo fire and killed 143,000 people and the more recent 1995 magnitude 6.9 Kobe earthquake that killed 5,500 people.

0 50 100 150 20025

Kilometers

SCALE 1:1,500,000Albers Equal-Area Projection

NEAR WEST COAST OF HONSHU, JAPAN

23 October 2004 08:56:01 UTC37.229 N., 138.773 E.Depth 16 kmMagnitude Mw = 6.6 (HRV)

A strong earthquake located near the western coast of northern Honshushook parts of northern Japan, particularly Niigata Prefecture, where itcaused at least 25 deaths, several thousand injuries, and significant damage to buildings and infrastructure. The deaths occurred principallyin the epicentral area near Ojiya, Nagaoke, and Tokamachi. Some esti-mates cited over 2,800 homes destroyed and more than 1,000 buildingsdamaged. Water, sewage, gas, and electrical power systems were seri-ously disrupted throughout the region and many towns were cut off bydamage to highways and railway tracks. The earthquake occurred onlydays after the passage of Typhoon Tokage; strong shaking on rainsoak-ed hillsides resulted in numerous mudslides and rockfalls . Two cars on the East Japan Railways bullet train traveling from Tokyo to Niigata de-railed in the epicentral area. Press accounts reported that tall buildings swayed in Tokyo approximately 190 km to the south. Felt in Chiba, Fu-kushima, Gumma, Kanagawa, Miyagi, Saitama, and Tokyo Prefectures.

EXPLANATIONMain Shock

23 October 2004

Aftershocks

Urban Area

SENDAIPopulated Place

Ishikawa

Highway

Freeway

Connector

Major Road

Railroad

Volcano

Azuma

125 130 135 140

145

125 130 135 140

145

25

30

35

40

45

25

30

35

40

45

Generalized Seismic Hazard

SOUTHKOREA

NORTHKOREA

RUSS

IAC H I N A

J A P A N

P A C I F I CO C E A N

S E A O F J A P A N

E A S TC H I N A

S E A

P H I L I P P I N ES E A

HONSHU

HOKKAIDO

KYUSHUSHIKOKU

R y u k

y u I

s l a

n d

s

I z u I s l a n d sB

o n i n I s l a n d s

S E A O FO K H O T S K

DETAILED MAP

P A C I F I CP L A T E

P H I L I P P I N EP L A T E

A M U RP L A T E

TOKYOTOKYO

YellowSea

SAPPOROSAPPORO

SEOULSEOUL

PYONGYANGPYONGYANG

O K H O T S KP L A T E

EXPLANATION

Main Shock

23 October 2004

Seismic Hazard

0.0 - 0.2 m/sec

0.2 - 0.4

0.4 - 0.8

0.8 - 1.6

1.6 - 3.2

3.2 - 6.4

6.4 - 9.4

Plate Boundary

Continental Convergent

Continental Rift

Continental LL Transform

Continental RL Transform

Oceanic Convergent

Oceanic Spreading

Oceanic LL Transform

Oceanic RL Transform

Subduction

Volcano

Seismic hazard is expressed as peak ground acceleration (PGA) on firm rock,in meters/sec, expected to be exceededin a 50-yr period with a probability of 10 percent.

MAJOR EARTHQUAKES 1900 - 1999 EPICENTRAL AREA

YR MO DY LAT LON DEPTH MAG

1900 5 11 38.700 141.100 5.0 7.0 1901 6 15 39.000 143.000 35.0 7.0 1905 7 6 37.400 141.800 35.0 7.1 1908 1 15 37.300 141.800 35.0 7.3 1914 3 14 39.500 140.400 5.0 7.0 1915 3 8 39.000 142.000 0.0 7.0 1915 11 1 38.300 142.900 35.0 7.5 1915 11 1 38.000 143.000 35.0 7.0 1921 12 8 36.000 140.200 35.0 7.0 1923 6 1 36.000 142.000 35.0 7.1 1924 8 14 36.133 141.892 35.0 7.0 1927 8 5 37.873 142.191 35.0 7.1 1928 5 27 39.813 142.999 35.0 7.1 1933 6 18 38.280 142.510 35.0 7.2 1936 11 2 38.337 142.151 35.0 7.1 1937 7 26 38.396 142.170 35.0 7.1 1938 5 23 36.458 141.755 35.0 7.7 1938 11 5 37.108 142.081 35.0 7.8 1938 11 5 37.009 142.045 35.0 7.9 1938 11 6 37.287 142.283 35.0 7.7 1938 11 6 36.867 142.625 35.0 7.0 1938 11 13 36.727 142.360 35.0 7.0 1939 5 1 39.839 139.969 35.0 7.0 1959 1 22 37.560 142.483 35.0 7.2 1962 4 12 38.073 142.741 24.5 7.2 1964 6 16 38.434 139.226 13.1 7.5 1965 9 17 36.336 141.327 43.5 7.1 1968 6 12 39.501 142.893 31.2 7.1 1978 6 12 38.224 142.009 53.3 7.7 1981 1 18 38.708 142.788 47.3 7.0 1982 7 23 36.307 141.763 27.4 7.0 1989 11 1 39.923 142.757 29.0 7.4 2003 10 31 37.829 142.634 10.0 7.5

RELATIVE PLATE MOTIONS

The relative motion of adjacent tectonicplates is depicted on the map by short vectors located at selected points on the plate boundary. In this presentation, one plate (the fixed reference plate) is assum-ed to be rigid. The vector therefore rep-resents the direction of the moving plate relative to the reference plate. The rate of relative motion is labelled next to the vector.

The components of the vector perpen-dicular and parallel to the plate margin approximate convergent/divergent and transverse direction of motion between the plates, respectively. As viewed from the fixed plate, an inward directed com-ponent suggests convergence at and near the plate boundary that may be ex-pressed as crustal folding, uplift, thrustfaulting, or plate subduction. Similarly, an outward directed component sug-gests plate divergence such as would be expected at a zone of crustal spread-ing. Transcurrent or transform faultingwould be expected when the predom-inant vector component is parallel to theplate margin.

DISCLAIMER

Base map data, such as place names and politicalboundaries, are the best available but may not be current or may contain inaccuracies and thereforeshould not be regarded as having official significance.

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

A1 A1'

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

A2 A2'

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

1200 km 1100 km 1000 km 900 km 800 km 700 km 600 km 500 km 400 km 300 km 200 km 100 km 0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

600 km

500 km

400 km

300 km

200 km

100 km

0 km

A3 A3'

EXPLANATIONDepth Classes

0 - 69 km

70 - 299

300 - 600

Magnitude Classes

5.0 - 5.9

6.0 - 6.9

7.0 - 7.9

Volcano

Depth Profiles

SCALE 1:15,000,000Albers Equal-Area Projection

0 100 200 300 40050

Kilometers

Perspective View

Vertical Exaggeration 3X

DATA SOURCES

EARTHQUAKES AND SEISMIC HAZARD USGS, National Earthquake Information Center NOAA, National Geophysical Data Center IASPEI, Centennial Catalog (1900 - 1999) Handbook of Seismology and Earthquake Engineering Global Seismic Hazard Assessment Program

PLATE TECTONICS Bird, P., 2003, An updated digital model of plate boundaries: Geochem. Geophys. Geosyst., v. 4, no. 3, pp. 1027 - 1080.

BASE MAP NIMA and ESRI, Digital Chart of the World USGS, EROS Data Center

NEWS SOURCES

Associated Press Reuters.Com