Support for Existing Western U.S. GPS Networks

Unavco, Inc., Boulder CO

Investigators

Abstract

0318549 Prescott This grant support the the ongoing operation and maintenance of 255 continuously operated global positioning system receivers (CGPS) that are a subset of 470 CGPS stations currently operational in the western U.S and one laser strainmeter system for a period of eighteen months. Through UNAVCO, Inc. governance, the geodetic/geophysics community selected 255 CGPS stations that are part of six heretofore independent regional GPS networks whose development and operational costs have been previously supported through multiple sources including NSF, NASA, NOAA, USGS and the Keck Foundation. Stations now a part of the Southern California Integrated Geodetic Network (SGICN), the Bay Area Regional Deformation Network (BARD), the Basin and Range Geodetic Network (BARGEN), the Eastern Basin and Range-Yellowstone GPS network (EBRY), the Pacific Northwest Geodetic Array (PANGA), and the Alaska Deformation Array (AKDA) will be operated and maintained as a coherent unit, with oversight management, equipment replacement coordination and engineering assistance from UNAVCO, Inc. facility and headquarters employees and additional efforts by regional network scientists and engineers through subcontracts to the University of Southern California (SCIGN), UC-Berkeley (BARD), Caltech (BARGEN), Smithsonian Astrophysical Observatory (BARGEN), University of Utah (EBRY), Central Washington University (PANGA), and the University of Alaska (AKDA). A primary goal of this project is to provide for the ultimate integration of CGPS receivers in the above listed western U.S. regional GPS networks into the Plate Boundary Observatory (PBO) component of EarthScope. The design goals of PBO include: 1) the operation of 875 CGPS stations consisting of a backbone array of CGPS receivers with approximate 200 km spacing extending along the western margin of North America from Mexico to Alaska and from the west coast of the U.S. eastward to the Rocky Mountain Plateau and additional denser clusters of CGPS receivers proximal to selected volcanic and fault structures; 2) an array of 175 distributed borehole strainmeters, and; 3) five long baseline laser strainmeters. This proposal provides temporary funding for operations and maintenance support for currently operating GPS stations in the western U.S. that may ultimately become part of the PBO backbone and supported through the NSF/MREFC EarthScope operations and maintenance budget five years hence A lengthening of the available core PBO CGPS time series is intended to serve the broader instrumentation system related goals of EarthScope/PBO to: 1) detect and understand transient deformation process on timescales from days to decades; 2) constrain uncertainties which can plague precise observation of the vertical deformation field observed by CGPS receivers and thereby allow for discrimination between various geophysical models of solid earth deformation, and; 3) enhance our understanding of the various low frequency noise sources that can preclude GPS observation of the most subtle tectonic signals. ***