Impact of OpenQuake Engine v 1.0 launch on worldwide #seismic hazard assessment, Marco Pagani, GEM Lead Hazard Scientist #GEMRVL2013

1. OpenQuake: Impact of Engine 1.0 launch
on worldwide seismic hazard assessment
Marco Pagani, GEM Hazard Team, GEM Foundation
Damiano Monelli, GEM Hazard Team, SED-ETH
Graeme Weatherill, GEM Hazard Team, GEM Foundation
Laurentiu Danciu, GEM Hazard Team, SED-ETH
on behalf of the GEM Risk, the GEM IT Teams and the GEM Community

2. Motivations
“anything less than release of the actual source code is an
indefensible approach for any scientific result that
depends on computation, because not releasing such
code raises needless, and needlessly confusing roadblocks
to reproducibility” (Ince et al., 2012; Nature)
Reproducibility and transparency
We wanted to shift from the current one-
one-one paradigm to the one-many-many
development model. Only in this way it’s
possible to ensure long term maintenance,
incorporate newest ideas and features and
aim at a large community of users.
A community based development
process A multi-HW and multi-OS
software

3. Main features
A modular software
OQ-engine is organized into a
number of libraries
oq-hazardlib
oq-risklib
oq-nrmllib
A multi-purpose tool
A software for the calculation of hazard
and physical risk
Hazard Risk
Open and transparent
Take a look at
http://github.com/gem

4. Main features (contd)
Documented
We produce documentation explaining
how to use the oq-engine and the
methods
Tested
Testing is an integral part of the
development process

5. The OpenQuake-engine risk module

6. OQ-engine risk module
The risk module of the oq-engine is currently comprised of five
risk calculation workflows:
• Two calculate losses and damage distributions due to a single
earthquake
• Two calculate seismic risk using probabilistic seismic hazard
• One uses loss exceedance curves to assess whether
retrofitting measures would be economically viable or not
Main result typologies:
• Loss maps, loss statistics, loss curves, total loss curve
• Damage distribution per asset or per taxonomy, collapse maps
• Benefit/cost ratio map

7. The OpenQuake-engine hazard module

8. The oq-engine natively support PSHA input models accounting
for epistemic uncertainties by means of a logic tree structure.
The input generally consists of:
- Configuration file
- Seismic source model logic tree
- Ground motion logic tree
Input model

9. A collection of source typologies
Five source typologies:
‒ Point Source
‒ Area Source
Can be used for
modeling distributed
seismicity
Can be used for
modeling shallow
crustal faults,
subduction faults
Without floating ruptures
With floating ruptures
‒ Simple Fault Source
‒ Complex Fault Source
‒ Characteristic fault Source

10. A growing list of Ground Motion Prediction Equations
for different Tectonic Regions
Stable continental regions
‣ Atkinson and Boore (2006)
‣ Campbell (2003)
‣ Toro et al. (1997)
Shallow Earthquakes in Active
Tectonic R.
‣ Abrahamnson and Silva (2008)
‣ Akkar and Bommer (2010)
‣ Akkar and Cagnan (2010)
‣ Akkar et al. (2013)
‣ Boore and Atkinson (2008)
‣ Cauzzi and Faccioli (2008)
‣ Chiou and Youngs (2008)
‣ Sadigh et al. (1997)
Subduction
‣ Atkinson and Boore (2003)
‣ Lin and Lee (2008)
‣ Youngs et al. (1997)
‣ Zhao et al. (2006)

11. Calculators:
‣ Classical Probabilistic Seismic Hazard Analysis (PSHA)
‣ Event-based PSHA
‣ Scenario hazard
‣ Disaggregation (currently only for Classical PSHA)
One code serving different needs …

12. Classical PSHA Calculator
rativeexamples
(a)

13. Event-based PSHA calculator

14. Scenario hazard calculator

15. Disaggregation calculator

16. Incorporating models from the community
‣ United States 2008 (USGS)
‣ Canada (Canada Geological Survey)
‣ Alaska 2007 (USGS)
‣ Japan 2012 (J-SHIS – NIED)
‣ Australia (Geoscience Australia)
‣ Taiwan (Cheng et al., 2007)
‣ SHARE (Regional program for the Europe)
‣ EMME (Regional program for the Middle East)
‣ South America 2010 (USGS)
‣ Global Uniform Model

17. Incorporating models from the community
OpenQuake-engine NIED

18. Testing typologies in the OpenQuake-engine:
- Unittests
- Quality-assurance tests
“Many of these scientists rely on the fact that the software has
appeared in a peer-reviewed article, recommendations, and
personal opinion, as their reason for adopting software. This is
scientifically misplaced, as the software code used to conduct the
science is not formally peer-reviewed.” (Joppa et al., 2013;
Science)
Testing, testing, testing

19. OQ
PEER
Testing, testing, testing

20. Application examples

21. Verification calculations SSHAC Level 3 project
‣ An application of the Classical-PSHA methodology
‣ SSHAC level 3 and 4 are the most sophisticated PSHA models
‣ Compared the results of some Ground Motion Prediction
Equations implemented in OQ-engine against the ones
prepared inside the project using a commercial software for
Probabilistic Seismic Hazard Analysis
‣ Computed hazard curves for a selected set of test cases

22. Verification calculations SSHAC Level 3 project

23. Index Event Table for the Bosphorus 1 deal
‣ An application of the Event-based PSHA methodology
‣ Computed Stochastic Event Sets (SES) of different duration
using one of the SHARE models
‣ From SES we
obtained a collection
of spatially correlated
Ground Motion Fields
‣ For each Ground
Motion Field we
computed the
corresponding Event
Index

24. SHARE

25. Global Uniform Hazard Model

26. Where we are …

27. Future developments

28. Potential new features
Tsunami hazard
Tsunamis pose a serious risk
threat in several costal areas of
the world. A module in the OQ-
engine would be thus extremely
useful.
Short term hazard
The classical PSHA methodology
takes into account only
mainshocks. For this reason it
necessary to implement a
specialised calculator to be used to
for the assessment of losses
produced by long aftershock
sequences.
Non-parametric sources
This source typology will allow the
calculation of hazard virtually using
whatever PSHA input model. A non-
parametric source is a list of ruptures
each one with an associated probability
of occurrence in a given time span.
Near Source Effects
Some of the newest GMPEs
incorporate terms for accounting
near-source effects. Since the ground
motion close to faults is largely
controlled by phenomena their
incorporation into hazard can be of
paramount importance.

29. OpenQuake-engine 1.0
Released on June, 2013
http://globalquakemodel.org/openquake

30. Relative difference (%): J-SHIS – OpenQuake
Underestimation
probably due to
missing modeling of
correction for anomalous
seismic intensity distribution
Overestimation in inland
locations – J-SHIS uses point
ruptures – OpenQuake uses
finite ruptures