SI2-SSI: A Sustainable Community Software Framework for Petascale Earthquake ModelingThomas H. Jordan (USC), Jacobo Bielak (CMU), Yifeng Cui (UCSD), Kim B. Olsen (SDSU)

S C E Can NSF+USGS center

ScientificSoftwareElements

Users:

Reinsurance

USGS

SCEC

EERCsNEES

RiskManagement

EarthquakeEngineering

Insurance

EmergencyPreparedness

FEMA

EarthScope

Public GTLTera3DPseudo-

dynamic

UCVM

CyberShake

Broadband

SEISM-IO Work-flows

Hercules

AWP-ODC

SORD

SWP

OpenSHA

OpenSees

EarthquakeEngineeringGeoscience

ComputerScience

SEISMSimulation Framework Valid

ation

Fra

mew

ork

Validation Exercises

Horizontal Integration

Vertical Integration

The main goal of this project is to advance and inte-grate scientific software elements (SSEs) devel-oped by SCEC into a sustainable software environ-ment for integrated seismic modeling (SEISM) as a software ecosystem for physics-based seismic hazard analysis (SHA).

SEISM will support the use of HPC by earthquake scientists, engineers, and risk managers to create the simulation-based products needed to improve SHA, and will provide the earthquake modeling community with tools that include model formula-tion, verification, prediction and validation, with a sustainable software engineering framework.

SEISM will accommodate a new generation of time-dependent earthquake rupture models for earth-quake forecasting that will interface with other soft-ware such as OpenSHA and OpenSees to produce more accurate hazard maps and to simulate the seismic performance of structural and geotechnical systems, thus facilitating a “rupture-to-rafters” mod-eling approach to earthquake risk management.

SEISM will incorporate Cyber Science and Engi-neering tools and practices into seismic hazard analysis, and will engage, train and expand a di-verse STEM workforce of geoscientists, computer scientists, and earthquake engineers.

Goals

Impact

SEISM is a collaboration among disciplinary groups in geoscience, computer science, and earthquake engineering. Our work plan is therefore structured around synergistic activities among these three groups. Integration of the simulation framework is being coordinated primarily between the geosci-ence and computer science groups. The validation exercises will be jointly managed by the geoscien-tists and earthuake engineers using a validation framework developed by the latter in cooperation with our software development team.

Work Plan

SEISM will develop and test two main computational platforms (CyberShake and BroadBand) and multiple SSEs (SWP, SORD, AWP-ODC, Hercules, GTL, Tera3D). The two main platforms and their products will be made available across domains. An additional platform, UCVM, will be developed to support the seismic veloc-ity models and meshes/grids necessary for earthquake simulation software integration.

Computational Platforms and SSEs

The CyberShake Platform

The prototype CyberShake hazard model has indi-cated that the standard at-tenuation relations used in probabilistic SHA based on empirical attenuation rela-tions tends to underesti-mate the hazard probabili-ties in sedimentary basins. SEISM will continue to de-velop and advance the Cy-berShake platform as a simulation-based alterna-tive approach to seismic hazard analysis. This plat-form will allow users to access the different layers of hazard information: (1) hazard maps, (2) hazard cirves, (3) disaggregation of hazard data in terms of rupture magnitude and dis-tance, (4) rupture models of earthquakes with the highest hazard to site, and (5) simulated seismograms for particular locations.

The Broadband Platform

The Broadband platform generates 0-10 Hz ground motions using deterministic low-frequency and stochastic high-frequency simulations. The Broadband platform integrates different scientific software elements includ-ing rupture generation, low-frequency deterministic seismogram synthesis, high-frequency stochastic seis-mogram synthesis, and non-linear site effects. These complex scientific codes have been integrated into a system that supports easy on-demand computation of broadband seismograms. The Broadband platform is designed to be used by both geoscientists and engineers with some experience interpreting ground motion simulations.

High-Fidelity Forward Simulation Tools and Results

SEISM includes various HPC applications for high-fidelity forward simulation of rupture dynamics and wave propaga-tion (SORD, AWP-ODC, Hercules). These codes are developed to be highly efficient and scalable and have been tested in multiple verification and validation exercises.

The SEISM Project is supported by the National Science Foundation, award No. 1148493. Additional SCEC team members include: J.W. Baker, G.C. Beroza (Stanford); P. Chen (U. of Wyoming); E.M. Dunham (Stanford); S.M. Day (SDSU); R.W. Graves (USGS); I. Iervolino (U. Naples, Italy); N. Luco (USGS); P.J. Maechling (USC); J.P. Stewart (UCLA); R. Taborda (CMU); F. Zareian (UCI). Private and international partners include: Pacific Gas & Electric Co. and the REAKT European project. Scientific publications and additional information about the various software elements and platforms can be found at http://scec.usc.edu/scecpedia and at www.scec.org.

Peak ground horizontal ground velocities (hot colors) and seismograms (white lines) from the M8 simulation of a “wall-to-wall” rupture of the southern San Andreas fault using AWP-ODC.

Validation from a 4-Hz simulation of the Mw 5.4 2008 Chino Hills earthquake in the Greater Los Angeles Region using Hercules; and compari-son of the seismograms at a particular location, recorded (white) and simulated (green).

The GreaterLos Angeles

Region

Pacif ic Ocean

2008Shino HillsEarthquake

Foodness-of-Fit Score4 100 2 6 8

RuptureGenerator(optional)

Low-FrequencySynthesis

High-FrequencySynthesis

Non-LinearSite Response

ExtractResponseSpectra

Verificationand Validation

(optional)

RuptureDescription

(SRF)

DeterministicSimulation

ObservedSeismograms(or alternative

simulation)

StochasticMethod

Longitude

Latitude−118.70−118.65

−118.60−118.55

−118.50−118.45

34.20

34.25

34.30

34.35

−20

−16

−12

−8

−4

0

0

50

100

150

200

250

300Slip (cm)

Cou

nt

0

20

40

60

0 1 2 3 4 5 6 7 8 9 10Score

0.1 1 100

100

200

300

0.1 1 100

100

200

0.1 1 100

50

100

150

0.1 1 100

10

20

30

Period (s) Period (s)

Sa (c

m/s

2 )Sa

(cm

/s2 )

Time (s)

CyberSHakePlatform

100

10-1

10-2

10-3

10-4

10-5

10-6

10-2 10-1 100

Prob

abilit

y R

ate

(1/y

r)

PGA (g)

1. Hazard Map

2. Hazard Curves

3. Hazard Disaggregation

4. Rupture Model

5. Seismograms

%C

ontri

butio

n

Rupture Distance (km)

40 50 60 70

0 10 20 30

80 90 100 110

20

16

12

8

4

0

Magnitud

e

5

6

7

8

9

Refinementand Partitioning

Meshingand Gridding

SourceGeneration

Solving

ForwardSimulation

1 00 1

Output Data

4D WavefieldStations, Planes, Volume

Model Formulation

SimulationParameters

SeismicVelocity Models