HR: 1340h
AN: IN43A-0907 [Abstracts]
TI: Using Google Earth to Explore Strain Rate Models of Southern California
AU: * Richard, G A
EM: Glenn.Richard@stonybrook.edu
AF: Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11794-2100, United
States
AU: Bell, E A
EM: BELLEA2@mailbox.sc.edu
AF: Department of Geological Sciences, University of South Carolina, Columbia, SC 29225,
United States
AU: Holt, W E
EM: William.Holt@stonybrook.edu
AF: Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, United
States
AB:
A series of strain rate models for the Transverse Ranges of southern California were developed based on
Quaternary fault slip data and geodetic data from high precision GPS stations in southern California. Pacific-North
America velocity boundary conditions are applied for all models. Topography changes are calculated using the
model dilatation rates, which predict crustal thickness changes under the assumption of Airy isostasy and a
specified rate of crustal volume loss through erosion. The models were designed to produce graphical and
numerical output representing the configuration of the region from 3 million years ago to 3 million years into the
future at intervals of 50 thousand years.
Using a North American reference frame, graphical output for the topography and faults and numerical output for
locations of faults and points on the crust marked by the locations on cities were used to create data in KML
format that can be used in Google Earth to represent time intervals of 50 thousand years. As markers familiar to
students, the cities provide a geographic context that can be used to quantify crustal movement, using the Google
Earth ruler tool. By comparing distances that markers for selected cities have moved in various parts of the
region, students discover that the greatest amount of crustal deformation has occurred in the vicinity of the
boundary between the North American and Pacific plates. Students can also identify areas of compression or
extension by finding pairs of city markers that have converged or diverged, respectively, over time. The Google
Earth layers also reveal that faults that are not parallel to the plate boundary have tended to rotate clockwise due
to the right lateral motion along the plate boundary zone. KML TimeSpan markup was added to two versions of
the model, enabling the layers to be displayed in an automatic sequenced loop for a movie effect. The data is
also available as QuickTime (.mov) and Graphics Interchange Format (.gif) animations and in ESRI Shapefile
format.
UR: http://www.eserc.stonybrook.edu/Strain/GoogleEarth/
DE: 0530 Data presentation and visualization
DE: 0545 Modeling (4255)
DE: 0810 Post-secondary education
DE: 0845 Instructional tools
DE: 3040 Plate tectonics (8150, 8155, 8157, 8158)
SC: Earth and Space Science Informatics [IN]
MN: 2007 Fall Meeting