Probabilistic seismic hazard assessment
for Taiwan: Application of OpenQuake
Chung-Han Chan

Marco Pagani

Ching-Tung Cheng詹忠翰鄭錦桐

National Taiwan University

Sinotech Engineering
Consultants Inc.

GEM Secretariat, Pavia

Why GEM?

“A collaborative effort devised and launched byOECD’s Global Science Forum, aimed at engaging theglobal community in the design, development anddeployment of state-of-the-art open models and tools
for earthquake risk assessment worldwide”
Taiwan has participate GEM since2012 using the organization ‘TEM’*OECD: Organisation for Economic Co-operation and Development

Main Modules of GEM

OpenQuake is the corresponding calculation engine

Model facility-Software development

Website: http://openquake.org
Installation: https://github.com/gem/oq-engine/wiki

Applications…

Different seismic sources are considered

Shallow area source

Active fault source

Subduction zone source

After Cheng et al. (2007)

Parameters for the shallow area sources
Treated as area sources in OpenQuake

The truncated exponential model is considered.

Parameters for the active fault sources
Treated as simple fault sources in OQ

The characteristic earthquake model is considered.
built-in GSIMs…

GSIMs are usually called from the build-in library

Considered GSIMs by Lin & Lee (2008)
for the subduction zone sources

Considered GSIMs by Lin (2009) for the crustal sources
A user becomes a contributor!
Created code for OpenQuake input

PSHA results…

High hazards along the active
faults in both east & west Taiwan
Probability of exceedance of 10 % in 50 yrs

Shallow
regional
sourceProbability of exceedance of 2 % in 50 yrs

Ý

ActivefaultsourceÝÝ

GMPEs of 2ֆ
Crust: Lin (2009)
Subduction: Lin & Lee (2008)ÝÝÝÝÝÝÝ

Seismic hazard map generated by OpenQuake (PGA, in g)
0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Similar results as those by Cheng et al. (2007)
Possible further application for TEM parameters
Probability of exceedance of 10 % in 50 yrs

Shallow
regional
sourceProbability of exceedance of 2 % in 50 yrs

Ý

Activefault
sourceÝÝ

GMPEs of 2ֆ
Crust: Lin (2009)
Subduction: Lin & Lee (2008)ÝÝÝCheng et al. (2007) resultÝÝ

Ý

Ý

Seismic hazard map generated by OpenQuake (PGA, in g)
0.00

0.10

0.20

0.30

0.400.50

0.60

0.70

0.80

Hazard curves…

PSHA in terms of hazard curves
Prob. of exceed.
in 50 years
100WLPHV

10ï

Taichung10ï
10 % in 50 yrs

TaipeiTaipei10ïTaichung10ïHazard
Low

High

10ï

0.0





0.6

0.8

1.0

Hazard curves (PGA, in g)Updated TEM components…

Implement the state-of-the-art parameters from TEM• Updated shallow sources- obtained by Prof. Kuo-Liang Wen• Different ground shaking intensity models- obtained by Dr. Yating Lee (poster in this Workshop)

Parameters for the shallow area sources
Treat as area sources in OpenQuake
S001

Ý
S002

Regression according tocatalog during 1900-2010

S012
S010

S004
S003

S006

S011

S005

S007

ÝÝ

S008
S013

Ý

S009

Ý

Ý

Ý

May 23, 2013

The truncated exponential model is considered.
PSHA results…

High hazards along the active
faults in both east & west Taiwan
Probability of exceedance of 10 % in 50 yrs

Shallow
regional
sourceProbability of exceedance of 2 % in 50 yrs

ÝActive
faultsourceÝÝ

GMPEs of 2ֆ
Crust: Lin (2009)
Subduction: Lin & Lee (2008)ÝÝÝÝÝ

Ý

Ý

Seismic hazard map generated by OpenQuake (PGA, in g)
0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

Similar patterns, smoother results
based on the Wen’s parameters
Shallow sources by Prof. Wen

Shallow
regional
sourceShallow sources by Dr. ChengÝ

Activefault
sourceÝÝ

GMPEs of 2ֆ
Crust: Lin (2009)
Subduction: Lin & Lee (2008)

Ý

Ý

Ý

Ý

Ý

Ý

Ý

Seismic hazard map generated by OpenQuake (PGA, 10% in 50 yrs in g)
0.00

0.10

0.20

0.30

0.40

0.500.60

0.70

0.80

GSIMs by Lee…

Ground motion behaviors in form of shaking duration

1994~2010';'Total:'N=395';''M>5.0;'Dep<50km

After Lee et al. (poster in this Workshop)

PSHA results…

Shallowregional
sourceÝ

ActivefaultsourceÝ

Shakingduration
Long

Ý

High hazards along theactive faults of west Taiwan& the northeast coastÝ
GMPEs of 2ֆ
Lee et al., in prep.

ÝShortÝÝ
Future works…

Future works• Implement the state-of-the-art parameters from TEM• Active fault parameters (Cheng et al., poster in this Workshop)• Historical earthquake catalog (Shyu et al., poster in this Workshop)• Ground shaking model (Lin et al. and Wen et al., orals in this Workshop)• Consider time-dependency• Both long-term and short-term (Chan et al., poster in this Workshop)• Further assess seismic risk
• When exposure & vulnerability parameters are available

Probabilistic seismic risk assessment impact canbe implemented according to the results of PSHA
HazardExposure*

Vulnerability*

Loss curve

Loss mapor/andTEM needs OpenQuake!
OpenQuake needs TEM!

Deﬁni&ons)of)dura&on)• Bracketed)dura&on))

M=5.5; D=27km (Dc=56.3km)

[Bolt(1973))and)Page)et)al.)(1975)]!

• Signiﬁcant)dura&on))[Husid)et)al.)(1969))and)Trifunac))and)Brady)(1975)])• This)study):))Pick)Waveform)Dura&on)Time)With)amplitude)>10.0gal)&))5%energy<E<95%energy))8.75)sec
Lee et al. (poster in this Workshop)

The incremental evenly-discretized distribution canbe applied for different seismicity rate models
The Truncated exponential model

The characteristic earthquake model

Berrill & Davis (1980)

Youngs & Coppersmith (1985)

Log(N) = a - b M

Timedependent
model
NP

Constrained byseismicity data

Increase

NumberofDecrease

Constrained bygeologic data

Forecast events:
Period: 2008-2009

eventsMagnitude

Mmax)RUHFDVWWLPH
End of 2009

Magnitude

Mmax

M
'HSWKNP

The Truncated exponential model• Cumulative a-valueintersection(a-value)• according to seismic catalog

Gutenberg-Richter Law
Log(N)= a - b M ± std dev• b-value

Estimated std. dev.
Estimated G-R law• according to seismic catalog• Minimum magnitudeNumberofevents

slopelue)• according to Mc of seismic catalog• maximum magnitudes• according to scaling law(b-vaMcMagnitude

After Gutenberg and Richter (1954)

The characteristic earthquake model• Slip area
• according to geology or geomophology data
• Slip rate
• according to geodetic or historical data
• b-value• according to seismic catalog• Maximum magnitude• according to scaling law

After Youngs & Coppersmith (1985)

OpenQuake can calculate

Possible application for the 1906 Meishan earthquake scenarioOpenQuake can calculate