The Smithsonian/NASA Astrophysics Data System

Abstacts on the EarthScope Plate Boundary Observatory in the Pacific Northwest of the United States from AGU (American Geophyscial Union) Annual Meeting, 2009

SAO/NASA ADS Physics Abstract Service

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Title: The EarthScope Plate Boundary Observatory (PBO)

High-rate Real-time Cascadia network

Authors: Jackson, M. E.; Austin, K. E.; Borsa, A. A.;

Eriksson, S. C.; Feaux, K.; Williams, T. B.

Affiliation: UNAVCO, Boulder, CO, United States;

Publication: American Geophysical Union, Fall Meeting 2009,

abstract #G21A-05

Publication Date: 12/2009

Origin: AGU

AGU Keywords: [1209] GEODESY AND GRAVITY / Tectonic deformation,

[1294] GEODESY AND GRAVITY / Instruments and

techniques

Bibliographic Code: 2009AGUFM.G21A..05J

Abstract

As part of the 2009 American Recovery and Reinvestment Act (ARRA), NSF is investing in onshore-offshore instrumentation to support studies of the Cascadia margin. EarthScope's Plate Boundary Observatory (PBO) will upgrade all 232 of its GPS stations in the Pacific Northwest to high-rate sampling and real-time telemetry and provide streaming data from this network to the public for scientific research, education, and hazard monitoring. This effort expands UNAVCO’s real-time GPS operations beyond its current pilot project of 100 stations to include a comprehensive regional network that spans the states of Washington and Oregon, and extends south into California to the Mendocino triple junction. By blanketing the Pacific Northwest with real-time GPS coverage, the NSF is hoping to create a natural laboratory in an area of great scientific interest and high geophysical hazard in order to spur new volcano and earthquake research opportunities. Streaming high-rate data in real-time will enable researchers to routinely analyze for strong ground motion monitoring and earthquake hazards mitigation. For stations with collocated meteorological instruments, met data will be streamed as well, opening the possibility for combined GPS/met processing in real time by the atmospheric community. Finally, the new funding also expands opportunities for research using high-rate GPS data from a large-aperture network, since 1 Hz streams will be permanently archived and freely available via FTP. PBO will provide 1Hz-streaming data in BINEX, RTCM2.3 and RTCM 3.0 formats via the NTrip protocol, from servers located at UNAVCO headquarters in Boulder, CO. Data latency will vary according to the telemetry deployed at each station, but is expected to range from 0.5~2.0 seconds given recent improvements in PBO's real-time streaming capabilities.

Title: The Plate Boundary Observatory (PBO) Network in the

PNW region of the United States

Authors: Hafner, K.; Austin, K.; Feaux, K.;

Jackson, M.; Fengler, K.; Doelger, S.

Affiliation:

UNAVCO, Inc., 801 S. Ruby Street, Ellensburg, WA 98926, United States

Publication: American Geophysical Union, Spring Meeting 2007,

abstract #G43A-02

Publication Date: 05/2007

Origin: AGU

AGU Keywords: 1209 Tectonic deformation (6924), 1242 Seismic cycle

related deformations (6924, 7209, 7223, 7230), 1294

Instruments and techniques, 1295 Integrations of

techniques

Bibliographic Code: 2007AGUSM.G43A..02H

Abstract

The Pacific Northwest Region (PNW) of the United States contains a variety of geologic regions and tectonic problems. These include the Cascadia Subduction Zone, Mt. St. Helens and the transition to the Basin and Range province. Since September of 2003, the Plate Boundary Observatory (PBO), which is part of the larger NSF-funded EarthScope project, has been installing a network of continuously operating GPS, strainmeter and tiltmeter instruments. There are currently 78 GPS, 13 strainmeter/borehole seismometers, and 4 tiltmeters operating in the PNW region. The data from this network has already been used to study Episodic Tremor Events (ETS) during September 2005 and January 2007, and renewed activity on Mt. St. Helens that began on September 23, 2004. The goal is have 134 continuously operating GPS stations by the end of September 2008. The locations of the GPS stations were determined by scientific committees. Whenever possible, multiple instruments are deployed at the same location, and share power and communications resources. Examples of this are GPS antennas mounted on top of strainmeter boreholes in the forearc region of western Washington and tiltmeters collecting data through GPS receivers on Mt. St. Helens. In addition, a number of stations provide real time kinematic data to professional surveyors within the region. During the fall of 2006, a 16 GPS and 4 tiltmeter station network was completed on Mt. St. Helens. Results from analysis of both PBO and USGS GPS stations on the mountain, show a radially inward and downward motion, with the maximum vertical offsets high on the mountain and the maximum horizontal offsets located at distances of 5-10km from the crater. Displacements are small over the 2004-present eruption with a maximum of 3cm of inward movement. GPS stations installed high on the mountain experience severe weather and heavy rime accumulations for approximately 6 months of the year. Ice build-up causes distortion of the GPS antenna phase center, and sun blockages on solar panels at several sites. Due to the large battery storage capacity, there have been very few power failures, however the build up of ice on the GPS antennas causes cm-level pseudo- displacements that mask the ground movements associated with the eruption.

Title: Update on Plate Boundary Observatory (PBO)

Activities in the Pacific Northwest

Authors: Hafner, K.

Affiliation: AA(UNAVCO, Inc., 801 S. Ruby St, Ellensburg, WA

98926 United States

Publication: American Geophysical Union, Fall Meeting 2006,

abstract #G53B-0899

Publication Date: 12/2006

Origin: AGU

AGU Keywords: 1209 Tectonic deformation (6924), 1294 Instruments

and techniques, 1709 Geodesy (1299)

Bibliographic Code: 2006AGUFM.G53B0899H

Abstract

The Plate Boundary Observatory (PBO), which is part of the larger NSF-funded EarthScope project, is nearing the end of year 3 of the installation phase of 852 continuously operating GPS stations in the Western United States. The Pacific Northwest (PNW) region will install 124 continuous GPS stations by the end of September 2008. The sites are distributed along the fore and back-arc of the Cascadia Subduction Zone and at Mt. St. Helens. At the end of September 2006, the PNW region will have met its year three installation goal of 75 GPS stations. The scientific priority during this past year was to complete the installations on Mt. St. Helens, and to continue to increase the density of the GPS network along the fore-arc regions of Washington and Oregon. UNAVCO will install a total of 16 GPS, 4 tiltmeter, and 4 borehole strainmeter stations on Mt. St. Helens. Seven stations were installed in 2004-2005. Nine additional GPS and the four tiltmeter and strainmeter stations will be installed in September of 2006. Data analysis from GPS stations installed to date indicate an inward and downward deflation of the volcano of several centimeters out to distances of 5 to 10km from the crater. UNAVCO will install 34 new continuous GPS stations in year 4, concentrated in the back arc regions of Oregon, the Idaho panhandle, and the Southwest Oregon fore arc region. Reconnaissance work for GPS site locations will continue in conjunction with suggestions from the scientific community.

Title: Completion of the 16 station Plate Boundary

Observatory (PBO) network on Mt. St. Helens, WA

Authors: Austin, K.; Hafner, K.; Fengler, K.; Doelger, S.

Affiliation:

UNAVCO, 801 S Ruby St, Ellensburg, WA 98926 United States

Publication: American Geophysical Union, Fall Meeting 2006,

abstract #G53A-0869

Publication Date: 12/2006

Origin: AGU

AGU Keywords: 1200 GEODESY AND GRAVITY, 1209 Tectonic deformation

(6924), 1294 Instruments and techniques

Bibliographic Code: 2006AGUFM.G53A0869A

Abstract

The Plate Boundary Observatory (PBO), part of the larger NSF-funded EarthScope project, is completing year 3 of the installation phase of 852 continuously operating GPS stations in the Western United States. Some of these GPS stations are focused specifically on centers of volcanic activity. Mt. St. Helens is one of these volcanic areas of interest in the Pacific Northwest (PNW) region. The PNW region will complete the installation of a 16 station GPS network on Mt. St. Helens during September 2006. This work also includes the co-location and installation of tiltmeters at four of the existing GPS sites. Network upgrades will be completed to handle the increase in data flow from the new GPS stations as well as the data from the tiltmeters and strainmeters. New GPS site installations include six helicopter accessible sites, and three drive to sites on the south flank of the mountain. Higher elevation sites will be outfitted with an eight battery, three solar panel power array to keep the stations operational during winter months. The remaining sites use a four battery, three solar panel array that has proved sufficient at other GPS locations over the past 2 winters. All stations will communicate via one of 2 radio networks set up on the mountain. The northern radio network transmits data for ten stations through a microwave connection at the Johnston Ridge observatory that also provides communications for PBO strainmeter, tiltmeter and CVO equipment. The remaining 10 stations on the south side of the mountain, are relayed through a hub at Washington State University's Vancouver Campus that is also providing data services for CVO. Results from analysis of data from both PBO and USGS GPS stations on the mountain, show a radially inward and downward motion, with the maximum vertical offsets high on the mountain and the maximum horizontal offsets located at distances of 5-10km from the crater. Displacements are small over the 2004-present eruption with a maximum of 3cm of inward movement. Modeling of the data by Lisowski et al. (AGU 2006) only accounts for a volume loss that is one third of the amount of material erupted. GPS stations installed high on the mountain were subjected to severe winter weather and heavy rime ice accumulations over the last year. This ice build-up caused distortion of the GPS antenna phase center, and blocked sun access to the solar panels at several sites. Due to the large battery storage capacity, very few power failures occurred at these stations. However, the build up of ice on the GPS antennas caused cm-level pseudo-displacements that mask the ground movements associated with the eruption.