HR: 0800h
AN: G21B-1265    [Abstracts]
TI: GPS Installation Progress in the Southern California Region of the Plate Boundary Observatory
AU: * Walls, C
EM: walls@unavco.org
AU: Arnitz, E
EM: arnitz@unavco.org
AU: Bick, S
EM: bick@unavco.org
AU: Lawrence, S
EM: lawrence@unavco.org
AU: Feaux, K
EM: feaux@unavco.org
AU: Jackson, M
EM: jackson@unavco.org
AB: One of the roles the Plate Boundary Observatory (PBO), the geodetic component of the NSF-funded EarthScope project, is the rapid deployment of permanent GPS units following large earthquakes to capture postseismic transients and any long-term viscoelastic-response . The PBO Southern California region conducted responses to three earthquakes; the M6.5 San Simeon earthquake, the M6.0 Parkfield earthquake, and the M5.6 Anza earthquake. For each event, PBO began a response within hours and developed reconnaissance, prioritization, relocation, and deployment plans at the request of the PBO Transform Site Selection Working Group. The San Simeon event initiated the beginning of the PBO GPS station construction phase when 5 stations were located, permitted, and built within 38 days of the earthquake. For the September 28th, 2004, Parkfield earthquake, the PBO Transform Site Selection Working Group elevated the priority of two planned GPS stations (P539 and P532) sited to the south of the earthquake epicenter. Reconnaissance for five sites in Parkfield began the day following the earthquake and two permits were secured within three days of the earthquake. Materials and equipment for construction were brought along with the response team and within 4 days the first monument (P539) was installed. Following the June 12 M5.6 Anza earthquake, the first station was located, permitted, and built within 4 days and the second station within 12 days. Of the 875 total PBO GPS stations, 212 proposed sites are distributed throughout the Southern California region. Currently the production status is: 59 stations built (23 short braced monuments, 36 deep drilled braced monuments), 72 permits signed, 105 permits submitted and 114 station reconnaissance reports. Year 1 and 2 production goals are on schedule and under budget. The balance of 153 stations will be built over the next 3 years from Long Valley to the Mexico border in order of priority as recommended by the PBO Transform, Extension and Magmatic working groups. Volunteers from the California Spatial Reference Center and others within the survey community have aided in the siting and permitting process.
DE: 1200 GEODESY AND GRAVITY
DE: 1209 Tectonic deformation (6924)
DE: 1240 Satellite geodesy: results (6929, 7215, 7230, 7240)
DE: 1241 Satellite geodesy: technical issues (6994, 7969)
DE: 1294 Instruments and techniques
SC: Geodesy [G]
MN: Fall Meeting 2005