HR: 0800h
AN: G21C-0685    [Abstracts]
TI: Strain pattern in Southern California from geodetic measurements
AU: * Hackl, M
EM: matthias.hackl@geophysik.uni-muenchen.de
AF: Ludwig Maximilian University, Theresienstr. 41, Munich, 80333, Germany
AU: Malservisi, R
EM: roccom@lmu.de
AF: Ludwig Maximilian University, Theresienstr. 41, Munich, 80333, Germany
AB: Geodetic measurements above all GPS data provide outstanding possibilities in identifying and parametrizing active faults. However, the data has to be interpreted by a strain accumulation model to obtain fault parameters like slip rate, locking depth, or earthquake recurrence times. Different rheological assumptions about the earth deformation behaviour resulted in a variety of models, like elastic half space or elastic layer over viscoelastic half space. Depending on which model chosen for the geodetic data interpretation, the obtained fault parameters may vary strongly. We tested for the variation of fault parameters due to the use of models with different rheological assumptions (Savage and Burford, 1973; McCaffrey, 2006; Meade 2005; Savage and Prescott, 1978). We chose our test site, Southern California, San Andreas Fault Zone, due to the presence of dense networks of both GPS sites and well studied active faults and interacting strain accumulation patterns. We merged GPS velocity data sets from SCEC, SOPAC, PBO and the University of Miami to obtain dense spatial data coverage. We improve the accuracy of the model estimates by including geologic information like the spatial distribution of faults and seismic information like the thickness of the seismogenic crust to obtain the slip rate distribution among San Andreas Fault, San Jacinto Fault and Elsinore Fault and its change along this system.
DE: 1209 Tectonic deformation (6924)
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1242 Seismic cycle related deformations (6924, 7209, 7223, 7230)
DE: 8111 Continental tectonics: strike-slip and transform
DE: 8150 Plate boundary: general (3040)
SC: Geodesy [G]
MN: 2007 Fall Meeting