HR: 0800h
AN: G21A-0133    [Abstracts]
TI: The PBO Nucleus: Integration of the Existing Continuous GPS Networks in the Western U.S.
AU: * Blume, F
EM: blume@unavco.org
AF: UNAVCO, 6350 Nautilus Dr., Boulder, CO 80301-5554
AU: Anderson, G
EM: anderson@unavco.org
AF: UNAVCO, 6350 Nautilus Dr., Boulder, CO 80301-5554
AU: Freymueller, J T
EM: jfreymue@gi.alaska.edu
AF: University of Alaska, Fairbanks, P.O. Box 757320, Fairbanks, AK 99775
AU: Herring, T A
EM: tah@chandler.mit.edu
AF: M.I.T., 77 Massachusetts Avenue, Cambridge, MA 02139
AU: Melbourne, T I
EM: tim@geophysics.cwu.edu
AF: Central Washington University, Dept. of Geological Sciences, Ellensburg, WA 98926
AU: Murray, M H
EM: mhmurray@seismo.berkeley.edu
AF: University of California, Berkeley, 215 McCone Hall, Berkeley, CA 94720
AU: Prescott, W H
EM: prescott@unavco.org
AF: UNAVCO, 6350 Nautilus Dr., Boulder, CO 80301-5554
AU: Smith, R B
EM: rbsmith@mines.utah.edu
AF: University of Utah, 135 So. 1460 East, Rm. 702, Salt Lake City, UT 84113
AU: Wernicke, B
EM: brian@gps.caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125
AB: Tectonic and earthquake research in the US has experienced a quiet revolution over the last decade precipitated by the recognition that slow-motion faulting events can both trigger and be triggered by regular earthquakes. Transient motion has now been found in essentially all tectonic environments, and the detection and analysis of such events is the first-order science target of the EarthScope Project. Because of this and a host of other fundamental tectonics questions that can be answered only with long-duration geodetic time series, the incipient 1400-station EarthScope Plate Boundary Observatory (PBO) network has been designed to leverage 432 existing continuous GPS stations whose measurements extend back over a decade. The irreplaceable recording history of these stations will accelerate EarthScope scientific return by providing the highest possible resolution. This resolution will be used to detect and understand transients, to determine the three-dimensional velocity field (particularly vertical motion), and to improve measurement precision by understanding the complex noise sources inherent in GPS. The PBO Nucleus Project is designed operate, maintain and upgrade a subset of six western U.S. geodetic networks: the Alaska Deformation Array (AKDA), Bay Area Regional Deformation network (BARD), the Basin and Range Geodetic Network (BARGEN), the Eastern Basin and Range/Yellowstone network (EBRY), the Pacific Northwest Geodetic Array (PANGA), and the Southern California Integrated Geodetic Network (SCIGN), until they are subsumed by PBO in 2008. Uninterrupted data flow from these stations will effectively double the time-series length of PBO over the expected life of EarthScope, and create, for the first time, a single GPS-based geodetic network in the US. Other existing sites will remain in operation under support from non-NSF sources (e.g. the USGS), and EarthScope will benefit from their continued operation. On the grounds of relevance to EarthScope science goals, geographic distribution and data quality, 209 of the 432 existing stations have been selected as the nucleus upon which to build PBO. We have begun converting these stations to a PBO-compatible mode of operation; data now flow directly to PBO archives and processing centers while maintenance, operations, and meta-data requirements are currently under upgrade to PBO standards.
UR: http://www.unavco.org/exnet/exnet.html
DE: 1206 Crustal movements--interplate (8155)
DE: 1208 Crustal movements--intraplate (8110)
DE: 1244 Standards and absolute measurements
DE: 1294 Instruments and techniques
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting