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SSC 306 Thompson 1 San Andreas and Other Fault Sources; Background Source SSC TI Team Evaluation Steve Thompson Diablo Canyon SSHAC Level 3 PSHA Workshop #3 Feedback to Technical Integration Team on Preliminary Models March 25-27, 2014 San Luis Obispo, CA PG&E DCPP SSHAC Study PG&E DCPP SSHAC Study 2 Overview of the Preliminary SSC Model SSC Elements: Key Fault Sources San Andreas and Other Regional Fault Sources Background Source PG&E DCPP SSHAC Study 3 San Andreas and Other Fault Sources San Andreas Fault Other 200-Mile Site Region Faults Goal: Goals: Capture maximum Complete SSC within 200-mi contribution of SAF Site Region Confirm past results about contribution of “other” faults PG&E DCPP SSHAC Study 4 San Andreas Fault Approach: Approximate UCERF3 Characterization Ten Sections in 200-mi Matched a composite “Participation MFD” Overestimates UCERF3 Solution PG&E DCPP SSHAC Study 5 San Andreas Fault Source Composite Participation MFD: P SC CR Pf Ch Cz BB MN MS (SB) = 1 2 3 4 5 6 7 8 9 풊 7.0, = 9 ( ) 푀 ≤ 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푖 푀 푖=1 PG&E DCPP SSHAC Study 6 San Andreas Fault Source Composite Participation MFD: P SC CR Pf Ch Cz BB MN MS (SB) = 1 2 3 4 5 6 7 8 9 풊 = 1 2 3 4 5 풌 7.0 < 7.5, = 5 ( ) 푀 ≤ 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푘 푀 푘=1 PG&E DCPP SSHAC Study 7 San Andreas Fault Source Composite Participation MFD: P SC CR Pf Ch Cz BB MN MS (SB) = 1 2 3 4 5 6 7 8 9 풊 = 1 2 3 4 5 풌 = 1 2 3 풏 > 7.5, = 3 ( ) 푀 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푛 푀 푛=1 PG&E DCPP SSHAC Study 8 San Andreas Fault Source Composite Participation MFD: P Ch MS P CR Ch BB MS P SC CR Pf Ch Cz BB MN MS (SB) = 1 2 3 4 5 6 7 8 9 풊 = 1 2 3 4 5 풌 = 1 2 3 풏 7.0, = 9 ( ) 푀 ≤ 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푖 푀 푖=1 7.0 < 7.5, = 5 ( ) 푀 ≤ 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푘 푀 푘=1 > 7.5, = 3 ( ) 푀 푅푅푅푅푇푇푇푇푇 푀 � 푅푅푅푅푛 푀 푛=1 PG&E DCPP SSHAC Study 9 San Andreas Fault Source Composite Participation MFD: Target MFD 1.E+00 ) 1 - 1.E-01 1.E-02 1.E-03 Composite SAF for DCPP 1.E-04 Cholame Participation UCERF3.3 1.E-05 Annual (yr Exceedance Annual of Rate 1.E-06 5.0 6.0 7.0 8.0 9.0 Magnitude (M) PG&E DCPP SSHAC Study 10 San Andreas and Other Fault Sources San Andreas Fault Other 200-Mile Site Region Faults Goal: Goals: Capture maximum Complete SSC within 200-mi contribution of SAF Site Region Confirm past results about contribution of Other faults PG&E DCPP SSHAC Study 11 “Other” Faults Other Faults within the 200-Mile Site Region UCERF3.3, Fault model 3.2 Additional offshore faults from LTSP PG&E DCPP SSHAC Study 12 “Other” Faults Index of Detailed Maps of Other Faults within the 200-Mile Site Region PG&E DCPP SSHAC Study 13 “Other” Faults Other Site Region Faults, Detail Greater San Francisco Bay Area PG&E DCPP SSHAC Study 14 “Other” Faults Other Site Region Faults, Detail Central California Coast Ranges PG&E DCPP SSHAC Study 15 “Other” Faults Other Site Region Faults, Detail Southern Coast Ranges and Western Transverse Ranges PG&E DCPP SSHAC Study 16 “Other” Faults Other Site Region Faults, Detail Southern Sierra Nevada and Mojave Areas PG&E DCPP SSHAC Study 17 “Other” Faults Other Site Region Faults, Detail Transverse Ranges, L.A. Basin, and California Borderlands Areas PG&E DCPP SSHAC Study 18 “Other” Faults Geometry – UCERF3.3, Fault Model 3.2 Added: Santa Lucia Bank fault; Queenie, Lompoc, and Purisima structures (from LTSP) Removed: Hosgri, San Gregorio, Los Osos, Shoreline, San Luis Bay, San Luis Range; San Andreas fault PG&E DCPP SSHAC Study 19 “Other” Faults: Source Characterization Logic Tree, UCERF3 faults Geometry Sense of Slip Rate Slip Slip Rate Weighting Scheme (following UCERF3.3) Geologic UCERF3.3 [0.3] UCERF3.3 UCERF3.3 (Weighted Mean Zeng FM 3.2 Apx. B Target Rate) [0.3] FM 3.2 [1.0] [1.0] [1.0] [0.5] NeoKinema [0.3] ABM FM 3.1 [0.1] [0.5] PG&E DCPP SSHAC Study 20 “Other” Faults: Source Characterization Logic Tree, LTSP offshore faults Fault Source Dip and Sense Slip Rate (Primary Reference) of slip 1 mm/yr* Santa Lucia Bank 45 NE, RL-R (Miller and Meltzer, [1.0] [1.0] 1999) 0.1 mm/yr* Queenie 40 NE, R (Clark et al., 1991) [1.0] [1.0] Purisima, 0.1 mm/yr † † Lompoc 40 NE, R (Willingham et al., [1.0] [1.0] 2013) †Assumed Equivalent to Queenie SSC *Rounded up from cited or estimated rate PG&E DCPP SSHAC Study 21 “Other” Faults: Source Characterization Logic Tree (cont.) Magnitude Mchar Mmax PDF Mchar weighting scheme Magnitude- Fault Area HB02 YC85 (weighted) Mchar + 0.25 (~ Log A + 4) [0.5] [1.0] [1.0] EB (Log A + 4.2) [0.5] PG&E DCPP SSHAC Study 22 Background source Poorly resolved sources of seismicity Undefined faults Goals: Complete SSC within 200-mi Site Region Confirm past results about contribution of Background source PG&E DCPP SSHAC Study 23 Background source Approach: Use historical seismicity rate, G-R distribution Be conservative – include seismicity associated with on fault sources Consider alternative characterizations: UCERF2 gridded seismicity UCERF3 gridded seismicity PG&E catalog, areal zonation Felser catalog, areal zonation PG&E DCPP SSHAC Study 24 Background source UCERF2 gridded seismicity Mmax ~7.0 25 Diablo Canyon SSHAC Level 3 Study Thank You PG&E DCPP SSHAC Study .
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