The 3rd annual meeting of the seismic hazard assessment for the next generation map
China-Japan-Korea cooperative program
June 17 – 21, 2013, in Sendai, Japan

Uncertainty in the assessment ofseismic hazard

Toshihiro YAMADAOYORMS Corporation, Japan

Impact of Uncertainty in the Process of SHA• It is common for Probabilistic Seismic Hazard Assessment(PSHA) to take into account the uncertainty in the process ofhazard assessment.
• On the other hand, it is not so common for Scenario (deterministic)
Seismic Hazard Assessment (SSHA) to take into account theuncertainty.
• However, every process of seismic hazard assessment includes
some sort of uncertainty, so that the uncertainty should be taken
into account properly even for SSHA.
• Furthermore, when you assess damage or loss using the estimatedseismic hazard without taking into account its uncertainty
properly, it is possible that an unexpected result will be derived
because of non-linearity of fragility or vulnerability of theproperty (see next page).
Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

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Mean loss and Average loss
• The mean loss estimation is not coincide with the average loss
estimation considering uncertainty of seismic intensity.

"Probability Density"& "Loss Ratio"

1.00.9

µ=5.0
µ=5.5
µ=6.0
Vulnerability Func.
Mean Loss Ratio (µ=5.0)
Mean Loss Ratio (µ=5.5)
Mean Loss Ratio (µ=6.0)

0.8
0.7
0.6

0.5
0.4

µ=5.0, σ=0.5
Ave. Loss Ratio (µ=5.0)µ=5.5, σ=0.5
Ave. Loss Ratio (µ=5.5)µ=6.0, σ=0.5
Ave. Loss Ratio. (µ=6.0)

0.3
0.2
0.1
0.03

3.54 4.5 5 5.5 6 6.5
Instrumental Seismic IntensityⒸ 2013 OYO RMS Corporation, All Right Reserved.

77.53

Cause of uncertainty in the process of SHA• Source Effect: Magnitude, Asperity, etc.
• Pass Effect: Structure and physical property of the ground, etc.
• Site Effect: Surface geology, etc.
Site Effect

Pass EffectSourceEffectTechnical Reports on National Seismic Hazard Maps for Japan (2009), NIEDⒸ 2013 OYO RMS Corporation, All Right Reserved.

4Effect of Magnitude (1/3)• Nankai Trough M8.7 EQ: Central Disaster Prevention Council (2003)• Nankai Trough M9.0 Earthquake: Cabinet Office (2012)Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

5Effect of Magnitude (2/3)• Difference in JMA Seismic Intensity

M9.0M8.7Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

6Effect of Magnitude (3/3)• Difference in JMA Seismic Intensity between M9.0 & M8.7

mean

0.302

σ

0.394

quartilemin-1.459

25%tile0.042

median0.308

75%tile

0.565

max

2.196

(M9.0 － M8.7)Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

7Effect of Asperity (1/3)• 4 Asperity Models for Nankai Trough M9.0 Earthquake
Standard Case

East Case

West CaseNear Land CaseⒸ 2013 OYO RMS Corporation, All Right Reserved.

8Effect of Asperity (2/3)• Difference in JMA Seismic Intensity distribution
Standard Case

East Case

West Case

Near Land CaseⒸ 2013 OYO RMS Corporation, All Right Reserved.

9Effect of Asperity (3/3)

0.4
0.3

maximum

0.2

third quartile

0.1

medianfirst quartile

0.0

standard deviation

0.5• Variation in JMA Seismic Intensity for each meshminimum

4dnaredun

5erw
lo

5repup6rew
lo

6repupⒸ 2013 OYO RMS Corporation, All Right Reserved.

710

Standard Deviation of Attenuation Curves
Research

Data Source
K-NET
94 events, 6,017 records, 1996~1998

Shabestari & Yamazaki JMA(1999)
1,020 events, 3990 record, 1988~1996
JMA (M = 4 and over)Matsuzaki et al. (2006)
Morikawa et al. (2010)

JMA, Local Government etc.
554 events, 27,531 records, 1926~2005 ※K-NET, JMA, Local Government etc.
194 events, 11,919 records, 1963~2003

σ0.535
0.544
0.511
0.701
0.36

※ The database by Ishigaki & Takagi (2000) is used. The database covers 93,148 events
during 1926 to 1999. 6 recent events are added to data set in the study.

Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

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Spatial Interpolation of SI for Tohoku EQObservatory：K-NET, KiK-net☆：JMA for comparison○seismic intensity scale

7
6 upper
6 lower
5 upper
5 lower43 und under

K-NET + KiK-net + RASMO※

Estimated Seismic Intensity Map (JMA)※ RApid Shake Map simulator with Observed records

http://www.seisvol.kishou.go.jp/eq/suikei/eventlist.htmlⒸ 2013 OYO RMS Corporation, All Right Reserved.

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Spatial Interpolation Method (RASMO)• RASMO: RApid Shake Map simulator with Observed records• The program was developed by NIED Kawasaki Laboratory in the“Special Project for Earthquake Disaster Mitigation in Urban Areas(2002 – 2006)”Ⓒ 2013 OYO RMS Corporation, All Right Reserved.

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Prediction Error of Spatial Interpolation
Prediction Error: Standard Deviation = 0.323
Estimated Instrumental Seismic Intensity

7.0

6.5

6.0

5.5

5.0

4.5

4.0
4.0

4.5

5.0

5.5

6.0

6.5

7.0

Observed Instrumental Seismic IntensityⒸ 2013 OYO RMS Corporation, All Right Reserved.

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Thank you !
謝謝!
감사합니다!
Acknowledgements
We used K-NET and KiK-net data and RASMO for spatial interpolation study of seismic
intensity. We would like to express our deepest gratitude to NIED and those involved.
ContactToshihiro YAMADAOYORMS Corporation
Address: Akasaka MK Bldg. 4F, 4-9-9 AKASAKA,
Minato-ku, Tokyo, 107-0052, Japan
Phone: +81-3-6434-9801
Mail: toshihiro.yamada@oyorms.co.jpⒸ 2013 OYO RMS Corporation, All Right Reserved.

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