[ghsc-seminars] GHSC Seminar, Thursday, TOMORROW, Aug 29th @ 2 pm - Arthur Rogers, LLNL

[Rigler, Erin (Josh)]

(Note non-standard time - 2pm)

*Regional-Scale Fully Deterministic Broadband 3D HPC Simulations of
Earthquake Ground Motions on the Hayward Fault, San Francisco Bay Area,
Northern California*


*Arthur Rogers**Lawrence Livermore National Laboratory*

We are running regional-scale (~100 km) fully deterministic broadband (0-10
Hz) ground motion simulations for earthquakes on the Hayward Fault in the
San Francisco Bay Area of Northern California.  Simulations compute the
response of a 3D Earth model (developed by the USGS) with surface
topography and attenuation using the SW4 finite difference code running on
high-performance computers (HPC) at the US Department of Energy National
Laboratories.  Our simulations are fully deterministic and do not require
stochastic or hybrid methods for the high-frequency components.  We use
finely sampled kinematic rupture models and near-surface grid spacings of
5-10 meters.  Simulations were run on large-scale computing resources with
tens to hundreds of billions of grid points to resolve the broadband
seismic response including 3D wave propagation effects (e.g. basin
amplification, scattering).  Recent enhancement of SW4 to run on the
world’s most powerful HPC platforms composed of mostly graphics processing
units (GPU’s) has greatly improved computational efficiency and
throughput.  Simulated ground motions agree well with ground motion models,
such as those from the Pacific Earthquake Engineering Research (PEER)
Center Next Generation Attenuation project.  A suite of Hayward Fault
ruptures resolved from 0-5 Hz is used to illustrate repeatable path and
site effects due to 3D Earth structure.  We are testing the validity of the
USGS 3D model by comparing observed and simulated waveforms from moderate
(MW 3.5-4.5) earthquakes recorded in the region.




*Thursday, August 29th, 20192-3pm  (Mountain Time)USGS, 1711 Illinois
Street, Golden, COEntry Level Seminar Room (204)*

*Note: Please arrive *~5 minutes early* and *bring photo ID* for
airport-style security measures now in place at the USGS building.

Thank you,
GHSC Seminar Committee

Ben Mirus - bbmirus at usgs.gov
Josh Rigler - erigler at usgs.gov
Oliver Boyd - olboyd at usgs.gov
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://geohazards.usgs.gov/pipermail/ghsc-seminars/attachments/20190828/c41d322e/attachment.html>