CyberShake Project and
ShakeMaps
CyberShake Project
 CyberShake is a SCEC research project that is a physics-based
high performance computational approach to Probabilistic
Seismic Hazard Analysis (PSHA)
 It uses 3D seismic wave propagation simulations to predict
ground motions produced by earthquakes
 Supercomputers are used to run complicated algorithms that
can help predict ground motions
 Goal is to create maps that can predict how much the ground
will move when a fault ruptures in different locations in
Southern California
Probabilistic Seismic Hazard
Analysis (PSHA)

Help create maps of unstable zones based on historical records of fault ruptures

Combines the results of millions of vertical earthquake simulations into a map that
will show the distribution of how different places will be affected

Requires two inputs


A velocity or earth structure model
An earthquake rupture forecast

The first input uses information about geologic structure of the soil which
illustrates how fast seismic waves will travel though different soil and how much
shaking will occur at a given location

The second input requires identifying the location of active faults and determine
the recurrence interval for each fault
High Performance Computing
 High performance computation on supercomputers is required
to make ShakeMaps
 180 million tasks were ran on a supercomputer at Texas
Advanced Computing Center
 By using high performance computing the CyberShake
computational approach improves Probabilistic Seismic Hazard
Analysis (PSHA) calculations
 Wave propagation simulations can more accurately describe the
ground motion distribution over a given location
 Wave propagation simulations provide information about ground
motion intensity and how long the shaking will last
Creating Hazard Analysis Maps
 The new hazard maps predict more shaking in the L.A. basin
 Seismologist studied the soil in different locations to determine
how the earthquake will affect each type of soil
 Information of each fault is necessary for creating these maps
 Scientists figured out the recurrence intervals of each active
fault
 In Southern California it is difficult to create these maps because
of all the different soil and rock that exist beneath the surface
Hazard Analysis Map Uses
 These maps can predict how much the ground moves at
different locations
 Help illustrate which certain areas will be affected the
most
 Enable emergency response teams to determine what
areas had the most damage
 Engineers use these maps when constructing buildings
that will be able to withstand the predicted amount of
shaking
ShakeMaps
 ShakeMaps are created by the CyberShake project
 Are geographic representations of ground motion made
by an earthquake
 Highlight the severity of ground shakes throughout the
area around the epicenter
 The map shows the distribution of shaking intensity which
is color coded using Mercalli Intensity maps
Interpreting ShakeMaps
 Legend
 Star: location of Epicenter
 Colored triangles: indicate reporting
stations
 Table: Mercalli Intensity Scale rated
by a roman numeral from one to
twelve, twelve being the most
shaking and damage
How to Access ShakeMaps
 General ShakeMaps
 Go to www.usgs.gov
 Click on the yellow “Hazards” near the top of the screen
 Click on the “Earthquake Hazards” link
 Click on the link next to the “ShakeMap: Maps Depicting Shaking
Intensity” text
 Specific earthquake ShakeMaps
 Search the quake on Google and click a link that is from the USGS
website (one of the first few links)
 Click on the “Maps” tab towards the top of the screen
 Click on the map titled “ShakeMap”
Works Cited

Broadband Seismic Data Collection Center. “Glossary of Terms.” 23 Nov. 2010. Web. 20
July, 2011. <http://eqinfo.ucsd.edu/faq/glossary.php>.

USGS. “ShakeMaps.” 21 July 2011. Web. 20 July 2011.
<http://Earthquake.usgs.gov/earthquakes/shakemap>.

SCECpedia. “CyberShake.” 14 July 2011. Web. 20 July 2011.
< http://scec.usc.edu/scecpedia/CyberShake>.

Dubros, Aaron. “Tomorrow’s Forecast: Clear with a Chance of Tremors.” Texas Advanced
Computing Center. 10 Feb. 2010. Web. 20 July 2011. < http://cms.tacc.utexas.edu/featurestories/2010/clear-with-a-chance-of-tremors/>.

Texas Advanced Computing Center. “CyberShake.” University of Texas at Austin. Spring
2010. Web. 20 July 2011. < http://cmsprod.tacc.utexas.edu/fileadmin/templates/SubtacctemplateStaticDropdown/images/case
studies/CS_CyberShake.pdf>.