HR: 09:15h
AN: S51B-06 [PDF]
TI: MSLT, Multi Surface Light Table, a Tool for Viewing Faults Under Their Terrain
AU: * Siegel, H
EM: Herb.Siegel@jpl.nasa.gov
AF: California Institute of Technology
Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Li, P
EM: Peggy.Li@jpl.nasa.gov
AF: California Institute of Technology
Jet Propulsion Laboratory, 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AB:
The QuakeSim project [1] was created to develop a solid earth science framework for creating an understanding of active
tectonic and earthquake processes and to construct a fully interoperable system of tools for studying these processes.
QuakeSim framework includes a new federated fault database that defines earthquake faults. It also includes three major
simulation tools: GeoFEST, PARK and Virtual California. Virtual California is a Monte Carlo simulation that generates
simulated earthquakes on a network of fault segments that are mediated by elastic interaction. The most effective way to
visualize the geographic parameters of the faults is to display them as surfaces with their associated terrain. With low
cost, high performance graphics hardware, we are able to observe fault models with high-resolution terrain and elevation
interactively. Moreover, we are able to visualize the dynamic characteristics of the faults, such as the time-varying slip
and stress values generated by Virtual California. In addition to the visualization of faults in a 3D environment, mapping
dynamic parameters with appropriate visual features would lead to intuitive understanding of time dependent fault
interactions.
We built the Multi Surface Light Table (MSLT) as an interactive tool to view earthquake fault segments underneath its
associated terrain. The fault segments, represented as rectangular surfaces at a dip angle, are organized into collections,
i.e., faults. An interface was built in MSLT to query and retrieve fault definitions from the QuakeSIM fault database. MSLT
also reads time-varying output from the Virtual California simulation. The slip and stress are represented by color and
intensity variation on the fault segments. MSLT's interactive controls provide a virtual trackball, pan and zoom, simulation
playback, and simulation movie capture. In addition, MSLT also displays the geographical information of the fault segments
and their collections on text windows. Because of the extensive viewing controls, faults can be seen in relation to one
another and to the land as well as the ocean. These relations may be realized in simulations. Correlated slips in parallel
faults are visible in the playback of Virtual California simulation. This is an example of the ability of the visual cortex
to pick out complex relationships with ease when presented with an appropriate view.
In this presentation, we will describe the technologies used to build MSLT, the hierarchical data structure we used to
represent large terrain and image datasets in order to allow real-time pan and zoom, and the Java client used to interface
the QuakeSIM database. We will also demonstrate the operation of MSLT using California faults and Virtual California
simulation results.
[1] http://www-aig.jpl.nasa.gov/public/dus/quakesim/
DE: 5475 Tectonics (8149)
DE: 7209 Earthquake dynamics and mechanics
DE: 7215 Earthquake parameters
SC: Seismology [S]
MN: 2003 Fall Meeting