CyberShake Simulations for Path Effects near SONGS

Transcription

1 CyberShake Simulations for Path Effects near SONGS Feng Wang, Thomas H. Jordan, Robert Graves, Scott Callaghan, Philip Maechling, and the CME Collaboration

2 2 SCEC s CyberShake utilizes 3D simulations and finite-fault rupture descriptions to compute deterministic and probabilistic seismic hazard in. (Graves et al., 2010) s758 San Onofre

3 3 CyberShake: Simulation-based seismic hazard model ~7000 fault ruptures (UCERF 2) ~60 realizations per rupture multiple hypocenter locations, and pseudo-dynamic rupture descriptions ~440,000 rupture variations Slip Velocity Function Rise time GenSlip v2.1 (Graves and Pitarka, 2007) GenSlip v3.2 (Graves and Pitarka, 2010) Spatial slip distribution and rupture front Rise time for slip velocity function Slip directions (rake distribution)

4 4 CyberShake: Simulation-based seismic hazard model ~7000 fault ruptures (UCERF 2) ~60 realizations per rupture multiple hypocenter locations, and pseudo-dynamic rupture descriptions ~440,000 rupture variations 3D velocity structure, e.g. CVM-S4, CVM-Harvard Community Velocity Model 4.0, SCEC (CVM-S4)

5 CyberShake: Simulation-based seismic hazard model ~7000 fault ruptures (UCERF 2) ~60 realizations per rupture multiple hypocenter locations, and pseudo-dynamic rupture descriptions ~440,000 rupture variations 3D velocity structure, e.g. CVM-S4, CVM-Harvard Seismogram synthesis for 235 sites using reciprocity, and stochastic methods (EXSIM) ~10 8 broadband synthetic seismograms: LF(<0.5 Hz) + HF (up to 10 Hz) PGV, PGA, SA Hazard curves and maps 5

6 NGA (2008) Attenuation Relations used in National Seismic Hazard Maps CyberShake shows higher hazard in sedimentary basins relative to NGA GMPEs CyberShake (2009) Hazard Model NGA Campbell & Bozorgnia NGA Chiou & Youngs NGA Boore & Atkinson PoE = 2%/50 yr Source: NGA Abrahamson & Silva

7 Path effects can be explicitly calculated for each CyberShake source ln(sa) at 3.0 s 7

8 8 Site-specific effects, corrected using Vs30 effects of Boore and Atkinson (2008), are larger in CyberShake model than in other three NGA GMPEs (2008) Campbell and Bozorgnia Chiou and Youngs ln (SA) at 3.0 s Abrahamson and Silva CyberShake

9 9 Site-specific effects, corrected using Vs30 effects of Boore and Atkinson (2008), are larger in CyberShake model than in other three NGA GMPEs (2008) Z 2. Z 1. Campbell and Bozorgnia 5 0 Chiou and Youngs ln (SA) at 3.0 s Z 1. 0 Not simple function of basin depth Abrahamson and Silva CyberShake

10 Three-dimensional velocity models (CVM-S and CVM-H) have different basin structures around SONGS (Magistrale et al. 2000; Suess and Shaw 2003) 10

11 11 The major source of epistemic uncertainty is the 3D basin structure Site s758 San Onofre Annual Frequency of Exceedance PoE: 2% in 50 yr by factor of 2 3s SA

12 12 CyberShake Hazard Curves for s758 CVM-S4 0.5 s SA (g)

13 13 CyberShake Hazard Curves for s758 CVM-S4 1.0 s SA (g)

14 14 CyberShake Hazard Curves for s758 CVM-S4 3.0 s SA (g)

15 15 CyberShake Hazard Curves for s758 CVM-S4 5.0 s SA (g)

16 16 CyberShake Hazard Curves for s758 CVM-S s SA (g)

17 CyberShake layered seismic-hazard models 17 (Bazzurro and Cornell, 1999)

18 San Onofre Nuclear Generating Site Rose Canyon- Newport-Inglewood fault Elsinore fault Hazard curves s758 4 x 10-4 per yr Disaggregation Diagram 3.0 s SA (g) Figure generated using OpenSHA (Field et al. 2003) 18

19 19 San Onofre Nuclear Generating Site Rose Canyon- Newport-Inglewood fault Elsinore fault Hazard curves San Jacinto fault San Andreas fault s758 4 x 10-5 per year Disaggregation Diagram 3.0 s SA (g)

20 References Abrahamson, N. A. and W. Silva, Summary of the Abrahamson & Silva NGA Ground-Motion Relations, Earthquake Spectra, 24 (1), Bazzurro, P. and C. A., Cornell, Disaggregaion of seismic hazard. Bull. Seism. Soc. Am., 89, 2, Boore, D. M. and G. M. Atkinson, Ground-motion prediction equations for the average horizontal component of PGA, PGV, and 5%-Damped PSA at spectral periods between 0.01s and 10.0s, Earthquake Spectra, 24 (1), Campbell, K. W. and Y. Bozorgnia, NGA ground motion model for the geometric mean horizontal component of PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01 to 10s, Earthquake Spectra, 24 (1), Chiou, B. S.-J. and R. R. Youngs, An NGA model for the average horizontal component of peak ground motion and response spectra, Earthquake Spectra, 24 (1), Field, E. H., T. E. Dawson, K. R. Felzer, A. D. Frankel, V. Gupta, T. H. Jordan, T. Parsons, M. D. Petersen, R. S. Stein, R. J. Weldon II, and C. J. Wills, Uniform California earthquake rupture forecast, version 2 (UCERF2.0). Bull. Seism. Soc. Am., 99, Graves, R., T. H. Jordan, S. Callaghan, E. Deelman, E. H. Field, G. June, C. Kesselman, P. Maechling, G. Mehta, D. Okaya, P. Small, K. Vahi, CyberShake: A Physics-Based Seismic Hazard Model for, Pure Appl. Geophys., 168, N 3-4, Graves, R., and A. Pitarka, Broadband ground-motion simulation using a hybrid approach. Bull. Seism. Soc. Am., 100, 5A, Magistrale, H., S. M. Day, R. W. Clayton, and R. W. Graves, The SCEC reference three-dimensional seismic velocity model version 2, Bull. Seism. Soc. Am., 90, 6B, S65-S76. Mai P, Beroza G, A spatial random field model to characterize complexity in earthquake slip. J. Geophys. Res., 107(B11): doi: /2001jb Field, E. H., T. H. Jordan, and C. A. Cornell, OpenSHA: A developing community-modeling environment for seismic hazard analysis. 74, 4, SCEC wiki: last accessed on March 17 th, Suess, M. P., and J. H. Shaw, P-wave seismic velocity structure derived from sonic logs and industry reflection data in the Los Angeles basin, California, J. Geoph. Res., 108, B3. 20