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PG&E DCPP SSHAC Study

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 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: Capture maximum contribution of SAF

Goals: Complete SSC within 200-mi Site Region Confirm past results about contribution of “other” faults

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San Andreas Fault

Approach: Approximate UCERF3

Characterization Ten Sections in 200-mi Matched a composite

“Participation MFD” Overestimates UCERF3

Solution

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San Andreas Fault Source Composite Participation MFD:

P SC CR Pf Ch Cz BB MN MS (SB)

𝑀 ≤ 7.0,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑖(𝑀)9

𝑖=1

1 2 3 4 5 6 7 8 9 𝒊 =

PG&E DCPP SSHAC Study 6

7.0 < 𝑀 ≤ 7.5,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑘(𝑀)5

𝑘=1

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 𝒊 =

1 2 3 4 5 𝒌 =

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 𝒊 =

1 2 3 4 5 𝒌 =

1 2 3 𝒏 =

𝑀 > 7.5,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑛(𝑀)3

𝑛=1

PG&E DCPP SSHAC Study 8

𝑀 ≤ 7.0,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑖(𝑀)9

𝑖=1

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 𝒊 =

1 2 3 4 5 𝒌 =

1 2 3 𝒏 =

7.0 < 𝑀 ≤ 7.5,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑘(𝑀)5

𝑘=1

P CR Ch BB MS

𝑀 > 7.5,𝑅𝑅𝑅𝑅𝑇𝑇𝑇𝑇𝑇 𝑀 = �𝑅𝑅𝑅𝑅𝑛(𝑀)3

𝑛=1

MS Ch P

PG&E DCPP SSHAC Study 9

San Andreas Fault Source Composite Participation MFD:

1.E-06

1.E-05

1.E-04

1.E-03

1.E-02

1.E-01

1.E+00

5.0 6.0 7.0 8.0 9.0

Annu

al R

ate

of E

xcee

danc

e (y

r-1)

Magnitude (M)

Target MFD

Composite SAF for DCPP

Cholame Participation UCERF3.3

PG&E DCPP SSHAC Study 10

San Andreas and Other Fault Sources

San Andreas Fault Other 200-Mile Site Region Faults

Goal: Capture maximum contribution of SAF

Goals: Complete SSC within 200-mi 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

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“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

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“Other” Faults Other Site Region

Faults, Detail Central California Coast

Ranges

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“Other” Faults Other Site Region

Faults, Detail Southern Coast Ranges

and Western Transverse Ranges

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“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

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“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

[0.3]

NeoKinema

Geologic

[1.0]

[0.5] FM 3.1

FM 3.2 [0.5]

Zeng

[0.3]

ABM [0.1]

UCERF3.3 FM 3.2

UCERF3.3 Apx. B

Geometry Slip Rate Sense of Slip

[1.0]

[0.3] UCERF3.3

(Weighted Mean Target Rate)

[1.0]

Slip Rate Weighting Scheme

(following UCERF3.3)

PG&E DCPP SSHAC Study 20

“Other” Faults: Source Characterization Logic Tree, LTSP offshore faults

(Clark et al., 1991)

Fault Source (Primary Reference)

[1.0]

Slip Rate

0.1 mm/yr*

[1.0]

1 mm/yr*

[1.0]

0.1 mm/yr †

[1.0]

Dip and Sense of slip

[1.0]

[1.0]

45 NE, RL-R (Miller and Meltzer,

1999)

Santa Lucia Bank

Queenie

Purisima, Lompoc

†Assumed Equivalent to Queenie SSC

40 NE, R

40 NE, R †

*Rounded up from cited or estimated rate

(Willingham et al., 2013)

PG&E DCPP SSHAC Study 21

“Other” Faults: Source Characterization Logic Tree (cont.)

[1.0]

[0.5]

EB (Log A + 4.2)

HB02 (~ Log A + 4)

[0.5] YC85

Magnitude-Fault Area (weighted)

Magnitude PDF

Mmax Mchar

[1.0]

Mchar weighting scheme

Mchar + 0.25

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

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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

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PG&E DCPP SSHAC Study

Diablo Canyon SSHAC Level 3 Study

Thank You