VisualizingTERASHAKE

Amit ChourasiaVisualization Scientist

Visualization ServicesSan Diego Supercomputer center

Geon Visualization Workshop March 1-2, 2005

About Terashake

Large Scale Earthquake Simulation on Southern San Andreas

33 researchers, 8 Institutions– Southern California Earthquake Center– San Diego Supercomputer Center– Information Sciences Institute– Institute of Geophysics and Planetary Physics (UC)

University of Southern California– San Diego State University– University of California, Santa Barbara– Carnegie-Mellon University– ExxonMobil

Slide: Courtesy Marcio Faerman

About Terashake

– Description of fault structure– Description of velocity model (anelastic

seismic wave propagation speed through sediment basins and through rock)

– Validation of the anelastic seismic wave propagation code

– Description of the expected fault rupture scenario

Greek!!!

Slide: Courtesy Marcio Faerman

TeraShake Simulation Area• Rectangular region parallel to

San Andreas fault containing:–Los Angeles,–San Diego,–Mexicali,–Tijuana,–Ventura Basin,–Fillmore,–Southern San Joaquin

Valley,–Catalina Island,–Ensenada

• 600 x 300 x 80 km

Slide: Courtesy Marcio Faerman

TeraShake Earthquake Simulation

• Magnitude 7.7 earthquake on southern San Andreas• Mesh of 1.8 Billion cubes, 200 m

• 0.011 sec time step, 20,000 time steps: 3 minute simulation

• Kinematic source from Cajon Creek to Bombay Beach – 75 sec source duration

– 18,886 point sources

• 240 processors on San Diego SuperComputer Center DataStar

• ~ 20,000 CPU hours, over approximately 5 days wall clock

• ~ 47 million megabytes of output

• Asynchronous rendering of simulation output during ongoing computation

Slide: Courtesy Marcio Faerman

Vista

It is a multithreaded, platform independent, scalable and robust volume renderer uses out of core paging. Vista is built on Scalable Visualization Toolkit (SVT)

What Vista can do?

• Volume Render any size volume using out of core paging

• Large Image resolutions - any resolution possible

• Create walk around

data segments• Handles 2D meshes• IsoVoluming

<->IsoSurfacing

About Data

Scalar Surface (floats)• 3000 x 1500

ie 600 km x 300 km

=17.2 MB per timestep• 20,000 timesteps• 3 variables Vx, Vy & Vz

Velocity components• Total Scalar data = 1.1 TB

Scalar Volume (floats)• 3000 x 1500 x 400

ie 600 x 300 x 80 km^3

=7.2 GB per timestep• 2,000 timesteps• 3 variables Vx, Vy & Vz

Velocity components• Total Vol data = 43.2 TB

Other Data – check points,etc

Grand Total = 47.4 TB

Go! Visualize

• Velocity components

(Volumes and Surfaces)

-0.1                                     +0.1

Visualize ?what?

• Velocity within specific range

• Color ramps easily understood by scientists.

-50.0                                     +50.0 cm/s 250.0                              +250.0 cm/s

Visualize ?what?

• Context – Geographic location

• Context – Fault lines

• Simulation Time

Visualize ?what?

• Velocity components and magnitudes

• Velocity Cumulative peaks

• Velocity range and color schema

-50.0                                  +50.0 cm/s 0.0                             250.0 cm/s

One of the Surface Viz

• Movie Clip

One of the Volume Viz

• Movie Clip

Current Viz Effort

• Wave propagation in 3d

• Topography with wave propagation

• Movie Clip1 Movie Clip2

Without 3d Terrain With 3d Terrain

Tools we use

• Vista (Scalable Visualization Toolkit –SVT)

Command line volume renderer (Works!)

• Mesh Viewer

Interactive Volume renderer (Java based)

• Maya

• Adobe suite

• Other things that work

More Visualizations

Visit website

• http://vistools.npaci.edu/

See Software and Examples

SCEC Visualizations• http://vistools.npaci.edu/examples/scec.htm

Current Viz not enough ?Need more?what?

• Curl

• Divergence

• Directivity

• ?

• ??

• ???

Is 2d the ?limit?

• Ease in navigation/orientation by scientists?

• Ease of 3d perception on monitor?• What are interest zones/regions?• Analysis methods for 3d data?• ???

Are we ready for volumetric Visualization?

TeraShake2

– 16 large scale simulations– 250 Tbytes

• 480 wave propagation simulations– 2.5 Tbytes

• Integration between synthetic and observed data

• Inversion studies – Frechet Kernel database

Thanks for your patience!

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