some general implications of results
DESCRIPTION
Some General Implications of Results. Because hazard estimates at a point are often dominated by one or a few faults, an important metric is the participation MFD for each fault (we aggregate results from our ~2,000 subsections back onto the ~315 p arent sections to keep things manageable). - PowerPoint PPT PresentationTRANSCRIPT
Some General Implications of Results
Because hazard estimates at a point are often dominated by one or a few faults, an important metric is the participation MFD for each fault (we aggregate results from our ~2,000 subsections back onto the ~315 parent sections to keep things manageable).
Fault-section MFD plots over all Char logic-tree branches are available here:
http://opensha.usc.edu/ftp/kmilner/ucerf3/2012_10_14-fm3-logic-tree-sample-x5_run0/parent_sect_mfds/
http://opensha.usc.edu/ftp/kmilner/ucerf3/2012_10_14-fm3-logic-tree-sample-x5_run0/parent_sect_mfds/cumulative_nucleation_mfd_comparisons.csv
Some examples…
Mean & +/- StdevOfMean
+/- Stdev
Min & Max
Cumulative Mean
Participation MFD for 100 simulated annealing runs for the same branch and same equation set weights
Participation MFD for 100 simulated annealing runs for the same branch and same equation set weights
Mean & +/- StdevOfMean
+/- Stdev
Min & Max
Cumulative Mean
Mean, Min, and Max from all logic-tree branches
UCERF3 Mean
UCERF3 Mean Cumulative
UCERF2
Mean from all logic-tree branches
Participationvs
Nucleation
Mean, Min, and Max from all logic-tree branches
UCERF3 Mean
UCERF3 Mean Cumulative
UCERF2
Mean, Min, and Max from all logic-tree branches
UCERF3 Mean
UCERF3 Mean Cumulative
UCERF2
Other Aggregate Metrics (ERF based)
Not Yet Computed (1,440 takes time)
Hazard Map Comparisons
NSHMP Fortran code OpenSHA code
NSHMP 2008 (UCERF2)
Building-Code Implications via Risk Targeted Ground Motions (RTGM)
Figure 30. Comparison of probabilistic risk-targeted ground motions for 0.2-sec spectral acceleration at three California cities. In each plot the dark blue bins represent the summed weights of different RTGM values across the 480 UCERF2 time-dependent, logic-tree branches. The green Line represents the average UCERF2 value, the orange line represents the official values from the US Seismic Design Maps, (http://geohazards.usgs.gov/designmaps/us) and the four lines labeled “U3 …” represent UCERF3 Characteristic reference branches for all four deformation models. The RTGM values were computed using the weighted combination of the three Next Generation Attenuation relationships (NGAs) that were used in the 2008 NSHMP. Mean UCERF2 values are generally lower than the US Design Map RTGM because the former does not consider additional epistemic uncertainty on ground motion that was included in the 2008 NSHMP.
Statewide Portfolio Loss Analyses (Porter et al., in press in SRL)
OpenSHA
UCERF2 EAL tornado diagram
0.5 1.0 1.5 2.0
B-Faults b-value
Fault-slip rates
Deformation model
Connect more B faults?
A-fault solution type
Magnitude-area relationship
GMPE
Probability model
Expected annualized loss, $ billion
Empirical BPT, 0.3
CB2008 AS2008
A priori
Hanks & Bakun
False
D2.2
Unsegmented
0.8
Mo-rate bal
Ellsworth
True
D2.6
Segmented
0.0Median and weighted avg
0.5 1.0 1.5 2.0
B-Faults b-value
Fault-slip rates
Deformation model
Connect more B faults?
A-fault solution type
Magnitude-area relationship
GMPE
Probability model
Expected annualized loss, $ billion
Empirical BPT, 0.3
CB2008 AS2008
A priori
Hanks & Bakun
False
D2.2
Unsegmented
0.8
Mo-rate bal
Ellsworth
True
D2.6
Segmented
0.0Median and weighted avg
UCERF3 Char Branch
UCERF2 EAL tornado diagram
This capability will allow us to potentially trim non-important branches, plus accommodate those that remain.
What about aftershocks?NSHMP has removed aftershocks using the Gardner-Knopoff declustering algorithm (Gardner and Knopoff, 1974).
For our RELM region, 56% of M>5 events are main shocks and 44% are aftershocks according to this definition (Felzer, Appendix I)
GR b-value is 0.8 for declustered catalog (compared to 1.0).
We can apply this “filter” to UCERF3 ERFs
Now
Some Hazard Implications – Peter Powers