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Group 1 – ShakeOut | Poster Abstracts
distribution of steel buildings, we have recommended that the ShakeOut drill be planned with a
damage scenario comprising of 5% of the estimated 150 steel moment frame structures in the 10-30
story range collapsing (8 collapses), 10% of the structures red-tagged (16 red-tagged buildings),
15% of the structures with damage serious enough to cause loss of life (24 buildings with fatalities),
and 20% of the structures with visible damage requiring building closure (32 buildings with visible
damage and possible injuries).
Hudnut, K.W., L.M. Jones, and B.T. Aagaard (2007), “The Southern California ShakeOut Scenario,
Part 1: Earth Science Specification of a Big One,” Annual Meeting of the Seismological Society of
America. Abstract reference number 07-501.
Graves, R., B. Aagaard, K. Hudnut, L. Star, J. Stewart, and T. Jordan (2008), “Broadband Ground
Motion Simulations for a Mw 7.8 Southern San Andreas Earthquake,” manuscript in preparation.
1-039
MULTI-HAZARD DEMONSTRATION PROJECT: SEISMICALLY INDUCED
LANDSLIDE HAZARD ANALYSIS AND POTENTIAL DAMAGE TO LIFELINE
CROSSINGS FOR THE MW 7.8 SOUTHERN SAN ANDREAS EARTHQUAKE
SCENARIO Wilson RI, McCrink TP, Treiman JA, and Silva MA
As part of the scenario Mw 7.8 earthquake on the San Andreas Fault (Multi-Hazard Demonstration
Project), the California Geological Survey (CGS) analyzed potential seismically induced landslides
in four transportation and utility lifeline corridors for Southern California: Cajon Pass, San
Gorgonio Pass, Highway 14 near Palmdale, and Interstate 5 near Pyramid Lake. Although sitespecific
geotechnical data were limited in all areas, CGS’s familiarity with the geologic and
topographic conditions in similar Southern California settings provided background for analysis.
Our assessment consisted of: 1) compiling landslide inventories within the focus areas, 2)
performing pseudo-static slope stability and deformation (Newmark displacement) analyses on the
interpreted “worst case” locations of landslides and landslide prone areas, and 3) estimating the
style and magnitude of ground failure and its resulting damage to lifelines in the focus areas.
Results from analyses indicate that slope failures will be common in three of the four lifeline
corridor areas due to the prevalence of steep slope conditions, weak geologic formations, and
extremely high ground shaking levels. For some existing landslides Newmark displacement values
were calculated to be well over one-meter, which increases the potential for those landslides to
change behavior from a sliding block to a flow-type failure. Such failures could inflict considerable
damage to lifelines because of their increased internal disruption and long run-out distances. It is
estimated that damage caused by landslides, especially in the Cajon Pass and San Gorgonio Pass
areas, could take weeks or months to repair assuming full access and resources are available.
1-040
DIGITAL MAP LAYERS OF LIQUEFACTION AND LANDSLIDE SUSCEPTIBILITY
FOR THE SOUTHERN CALIFORNIA REGION IMPACTED BY THE SHAKEOUT
SCENARIO EARTHQUAKE Ponti DJ, and Tinsley JC
In order to evaluate regional liquefaction and landslide hazards caused by the ShakeOut scenario
earthquake, it was necessary to build a consistent set of digital map layers of ground failure
susceptibility for the entire 8-county study area. These layers consist of: (1) a 5-category
liquefaction susceptibility map; (2) two landslide susceptibility maps (for saturated and dry
conditions) that use 10 m slope-angle data specially derived for this study; and (3) an autumn timeperiod
depth-to-water-table map. These data can be readily imported into HAZUS-MH MR3 and
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