Initial Results from BBP Simulations

Jennifer L Donahue, PhD, PE Senior Engineer Geosyntec Consultants SWUS Ground Motion – Workshop 2 SSHAC Level III 22 October 2013

Agenda • Planned use of simulations

• Review of initial set of cases run

Planned Use of Simulations • Constrain hanging wall effect for lower magnitude (M5.5 and

M6) scenarios • Compare hanging wall scaling between modelers for mid-level

magnitudes (M6.5 and M7) scenarios • Estimate scaling of ground motions for complex ruptures • Estimate scaling of ground motions for splay faults

Hanging Wall Scenarios • Lower Magnitudes (30 scenarios)

• Mag: 5.5 and M6 • Dips: 10, 20, 30, 45, 60 • ZTOR: 2.5, 7, 12 km

• Mid-level Magnitudes

• Mag: 6.5 (5 scenarios) • Dips: 10, 20, 30, 45, 60 • ZTOR: 0 km

• Mag 7 (1 scenario) • Dip: 45 • ZTOR: 0 km

37 Scenarios 32 Realizations per

scenario 3 Methods 660,480 seismograms

Modeling of Complex and Splay Ruptures • Complex: a significant change in rake or dip along strike • Splay: one main fault with a secondary/branching fault

Complex and Splay Cases • Complex Scenarios:

• Hosgri (SS) – San Luis Bay (Rev) • Hosgri (SS) – Los Osos (Rev)

• Splay Scenarios: • Hosgri (SS) – San Luis Bay (Rev) • Hosgri (SS) – Los Osos (Rev) • Hosgri (SS) – Shoreline (SS)

Will also add in San Simeon and San Gregorio

Complex and Splay Cases • Modes

• Fixed hypocenter/random slip • Random hypocenter/random slip

• Model Width • Thick • Thin

14 Scenarios 32 Realizations per scenario 3 Methods 116,928 seismograms

Thank you