CyberShake Background Seismicity
From SCECpedia
Goal: determine the importance of background seismicity in different parts of CA to either validate it's exclusion in CyberShake or motivate an inclusion strategy.
UCERF2
Calculation parameters:
- GMPE: NGA-West2 GMPE (average of 4 models)
- ERF: UCERF2, with and without background seismicity
- Site Effects: Vs30 is from Wills (2015), no basin depth terms included
- IMT: 2 second SA.
| Model | 10% in 50yr | 2% in 50yr | 1% in 50yr |
|---|---|---|---|
| Excluding Background |  |
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| Including Background |  |
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| Ratio Exclude/Include |  |
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UCERF3
Calculation parameters:
- GMPE: NGA-West2 GMPE (average of 4 models)
- ERF: UCERF3, with the following configurations
- Supra-seismogenic ruptures only (only supra-seismogenic ruptures have finite fault surfaces in UCERF3, all others treated as gridded)
- Supra and Sub-seismogenic ruptures only (this adds gridded ruptures that correspond to sub-seimogenic ruptures on known faults)
- Supra, Sub-seismogenic, and off fault ruptures (complete model)
- Site Effects: Vs30 is from Wills (2015), no basin depth terms included
- IMT: 2 second SA.
| Model | 10% in 50yr | 2% in 50yr | 1% in 50yr |
|---|---|---|---|
| Supra-Seismogenic On-Fault Only |  |
 |
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| Sub+Supra-Seismogenic On-Fault Only |  |
 |
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| Complete Model (Supra+Sub+Off) |  |
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| Ratio Supra-Only/Complete |  |
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| Ratio Supra+Sub/Complete |  |
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