HR: 14:25h
AN: G32B-04 INVITED     [PDF]
TI: Results and Comparisions from the Southern California Integrated and other arrays
AU: * Herring, T A
EM: tah@mit.edu
AF: EAPS MIT, 77 Massachusetts Av, Cambridge, MA 02139 United States
AB: The Southern California Integrated GPS Network (SCIGN) was established after the 1994 Northridge Earthquake near Los Angeles, California. The SCIGN array is the largest integrated array in North America and was largely completed in July 2001. Currently the array has about 250 continuously operating GPS receivers. The current operation of SCIGN shares many of the characteristics sought for the operation of the plate boundary observatory. All of the data from SCIGN are freely available. SCIGN operates three analysis centers, one for near-real time processing and two for final post processing. There is also an analysis committee that compares and combines the results from the two post processing centers. This analysis committee makes available results in the form of time series, 3-dimensional velocity vectors, and postseismic deformation parameters from a uniform analysis of loosely constrained solution vectors with full covariance matrix information and from analyses preformed at the two post processing centers at Jet Propulsion Laboratory (JPL) and the Scripps Institution of Oceanography (SIO). (http://chandler.mit.edu/~tah/SCIGN). We present here comparisons of uniform processing of the solutions from JPL and SIO with the processing results presented by the two centers (http://sideshow.jpl.nasa.gov/mbh/series.html and http://sopac.ucsd.edu/cgi-bin/dbShowArraySitesMap.cgi?array =SCIGN). From these comparisons, the robustness of signals seen in strain field in the region and non-linear temporal variations in the time series can be assessed. The RMS difference of the 3-D velocities from the uniform analysis is 0.6 mm/yr, and for horizontal 2-D velocities 0.5 mm/yr. We will examine those sites where the two analysis centers do not agree well. In these cases, the differences arise from site characteristics such as the effects of snow, multipath, subtle instrument failures, and loading processes when different lengths of data are used. We will also examine results from other networks around the world where some of the effects discussed above are even more pronounced.
UR: http://chandler.mit.edu/~tah/SCIGN
DE: 1206 Crustal movements--interplate (8155)
DE: 1208 Crustal movements--intraplate (8110)
DE: 1229 Reference systems
DE: 1243 Space geodetic surveys
DE: 1294 Instruments and techniques
SC: Geodesy [G]
MN: 2003 Fall Meeting