Pacific Northwest Geodetic Array
Central Washington University

The Pacific Northwest Geodetic Array
& CWU Geodesy Laboratory


The Pacific Northwest Geodetic Array is comprised of the PANGA Geodesy Laboratory at Central Washington University and ~350 continuously operating, high-precision GPS receivers located throughout the Pacific Northwest. Data from these receivers is continuously downloaded, analyzed, archived and disseminated by the Geodesy Lab as part of the geophysics and tectonics research programs within the Department of Geological Sciences, Central Washington University.

Geodesy Laboratory

The Laboratory's primary scientific role is to support high precision geodetic measurements using Global Positioning System (GPS) observations in order to characterize crustal deformation, plate tectonic motions, coastal and earthquake hazards, and other environmental science applications. Under contracts from the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), the U.S. Geological Survey (USGS), and UNAVCO, Inc. (UNAVCO), the lab analyses all publically shared GPS data within the Cascadia subduction zone and greater Pacific Northwest. In addition, the Lab also analyzes data from roughly 1000 GPS stations that comprise the EarthScope Plate Boundary Observatory, whose stations span the Pacific-North American tectonic plate boundary from Alaska to Mexico. A map showing all stations currently analyzed by CWU is provided here.

Real-time GPS Data Analysis

Approximately one third of PANGA's GPS stations are telemetered in real-time back to CWU, where they are processed in real-time using both JPL's RTG software as well as Trimble's RTKNet Integrity Manager software to provide relative positioning of several mm resolution across the Cascadia subduction zone and its metropolitan regions. These real-time data are used to monitor and mitigate natural hazards arising from earthquakes, volcanic eruptions, landslides, and coastal sea-level hazards. In addition, they are also used to monitor man-made structures such as Seattle's sagging Alaska Way Viaduct, 520 and I90 floating bridges and power-generation/drinking-supply dams throughout the Cascadia subduction zone, including those along the Columbia River.

Analysis Techniques

The goal of measuring millimeter-scale tectonic displacements throughout the Pacific Northwest requires stringent analysis and parameter estimation techniques. The Lab uses NASA's Gipsy Oasis software to translate GPS satellite phase observables into position time series, and in-house parameter estimation and modeling software to quantify crustal deformation caused by plate tectonics, earthquakes, landslides and volcanic eruptions. In addition to serving as the Data Analysis Facililty for the Pacific Northwest Geodetic Array (PANGA), the CWU Geodesy Lab also supports field experiments on Cascades volcanoes and in mainland Mexico, Baja California, California, Idaho, Montana, Oregon, and Washington. CWU also operates a continuous GPS network in Nepal under the direction of Professor Beth Pratt-Sitaula.

Rinex and other data files are available from our public archive via anonymous ftp.

The laboratory is a major participant in the University NAVSTAR Consortium (UNAVCO), and the Plate Boundary Observatory (PBO). These activies are funded primarily by the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), and the U.S. Geological Survey (USGS).