News and information about the Plate Boundary Observatory operations is released periodically, with excerpts from monthly reports sent to the National Science Foundation. Additional reporting occurs annually and includes a five year report filed at the end of MREFC.
In October 2011, engineers from the Plate Boundary Observatory began work on an NSF-funded RAPID project related to the study of the post-rupture crustal relaxation due to the M5.8 earthquake that struck near Mineral, VA on August 23, 2011. The project consisted of the reconnaissance, permitting, construction, and data communications for two permanent GPS stations near Louisa, Virginia, close to the epicenter of the earthquake. UNAVCO field engineers assisted the Principal Investigator with all the components of the fieldwork. The project was completed in November 2011.
Beginning October 2011, UNAVCO will start releasing high-rate (1-sps) processed borehole strainmeter data for geophysical events of special interest, e.g., earthquakes, tsunamis, volcanic events or in response to community requests. The high rate strain data set will include areal and shear strain, earth tide plus ocean load time-series, barometric pressure corrections, plus pore pressure and tiltmeter data if they are collected at the site. These new data products will be available from the UNAVCO PBO web page under the Geophysical Event section. The first high rate data sets available are for the M9, March 11, 2011, Tohoku Earthquake and the M6.4, 2011 September 9, Vancouver Island Earthquake.
UNAVCO has released a new realization of the Plate Boundary Observatory (PBO) network GPS velocity field, reflecting data acquired through May 2011.
A few months earlier than anticipated, the 2011 Cascadia Episodic Tremor and Slip event may be underway. Based on the start time of last year's event, this year's tremor was expected to begin late October 2011. An increase in tremor south of Puget Sound around August 7th, however, and its propagation northeastwards under the Olympic Peninsula over the past 10 days has caused speculation that this is the main 2011 ETS event (http://www.pnsn.org/WEBICORDER/DEEPTREM/summer2011.html).
The Plate Boundary Observatory (PBO) worked hard in the fall of 2010 to install instrumentation in deep boreholes in the San Jacinto Fault area of southern. The area of focus was in the region of the town of Anza, located roughly halfway between the Salton Sea and the city of Riverside, California.
A magnitude 8.8 earthquake occurred on February 27th, 2010 at 3:34 AM local time (06:36 UTC) off the coast of the Maule region of central Chile (Figure 1). Intense shaking lasted for about three minutes and a tsunami generated in the Pacific Ocean.
New EarthScope airborne LiDAR data products from California and Washington state were announced in January 2010. With this release, DEM tiles and KML files from all southern and eastern California targets are now available, including faults in the Mojave (Lenwood, Helendale, Calico, Blackwater), eastern California (Panamint, Tin Mtn, Mud Hills, Hunter Mtn, Owens) and San Cayetano.
Beginning Jan 17th, 2010 at about 1:00 PM (MST) a significant swarm of earthquakes started in the Yellowstone area located about 16 km northwest of Old Faithful. According to the Yellowstone Volcano Observatory (YVO), "swarms have occurred in this area several times over the past two decades." As of Feb 5th, 2010 there have been 1778 recorded events, with the largest single event having a magnitude of 3.8 and the cumulative magnitude of the swarm near magnitude 4.4.
The January 10, 2010 M6.5 Gorda earthquake offshore California's Cape Mendocino occurred within 50 km of four GPS stations in the Plate Boundary Observatory (PBO) network. Static processing of data from these sites by the PBO analysis centers and the US Geological Survey has revealed up to 1 cm of primarily eastward displacement of these sites.
On Jan 9, 2010, a Magnitude (M) 6.5 earthquake occurred offshore of Northern California ~ 30 miles WSW of Eureka, CA (Figure 1). As reported by the USGS, the event occurred within the Gorda Plate on a near vertical fault plane oriented ~ N 47 E.
The Borehole Strainmeter (BSM) stations in Southern California observed an interesting sequence of earthquakes located in the Baja region on 12/30/2009. As with previous larger magnitude events there are smaller but with visible areal and shear strain signals.
The tiny Aleutian village of Akutan, perched precariously under Akutan volcano, hosts one of the most important data telemetry sites in the entire Plate Boundary Observatory (PBO) network. Data from 18 stations converge in this village where they are uploaded through the Internet to the PBO Archive in Boulder.
GPS data from the Plate Boundary Observatory's station at Marshall Field in Colorado is being used by Kristine Larsen at the University of Colorado at Boulder to measure snow depth around the station monument.
The EarthScope Plate Boundary Observatory strainmeters in Southern California recorded significant strain offsets following the passage of seismic waves from the M6.9 Gulf of California earthquake on August 3.
GeoEarthScope recently announced the availability of new airborne Light Detection and Ranging (LiDAR) data products from the Intermountain Seismic Belt project. This release includes high resolution LiDAR topography data collected in tectonically active regions of Utah and Wyoming, including Yellowstone and Grand Teton National Parks and the Nephi segment (southern strand) of the Wastach fault.
The Plate Boundary Observatory (PBO) is part of the larger National Science Foundation (NSF)-funded EarthScope project. This geodetic observatory is designed to study the four-dimensional strain field resulting from deformation across the active boundary zone between the Pacific and North American plates in the western United States and Alaska. The network will provide an unprecedented spatial and temporal view of western North America enabling Earth scientists and the natural hazards community to better understand earthquake and volcano behavior.
The M4.8, March 24, 2009, Bombay Beach Earthquake and the earthquake swarm that followed it were recorded by the PBO Long Baseline Laser Strainmeter at Durmid Hill (DHL).
EarthScope seismic, strain and GPS data are currently aiding scientists in interpreting the ongoing earthquake swarm under Yellowstone National Park that began on December 27, 2008 and ended in early January, 2009. Scientists are carefully studying the seismic and GPS data to evaluate the cause of this swarm that appears to have been related to hydrothermal and tectonic processes.
The Plate Boundary Observatory (PBO) has transitioned from facility construction to operations and maintenance as of October 1, 2008.
On August 17, 2008, a creep event was recorded along the Parkfield segment of the San Andreas Fault. PBO strainmeter B073 recorded a 50 nanostrain shear strain transient over 30 minutes while a USGS creepmeter in the area, xva1, recorded 1.5 mm of right lateral slip.
The PBO Nucleus Project, which will update and incorporate 209 existing GPS stations into the PBO network, is within a month of completion.
On August 24, 2008 PBO construction crews completed the installation of 14 GPS, 8 tiltmeters, and one webcam on Unimak Island, the remote easternmost island of the Aleutian chain in Alaska.
The PBO Parkfield strainmeter network consists of 8 borehole tensor strainmeters.
A Mw 5.4 earthquake shook southern California on July 29, 2008, just before noon. It was located 4 km southwest of Chino Hills, CA, 46 km ESE from Los Angeles, and occurred at a depth of 14.7 km. This location puts it within 50 km of over 40 PBO GPS monuments, as well as a cluster of seven borehole strainmeters about 90 km to the southeast.
The second phase of a three-phased project for installing thirteen PBO GPS sites on Unimak Island, the largest and easternmost island in the Aleutian Island chain of Alaska, is underway. The first phase (July 12-31) involved preparation work for installing the sites, based out of Cold Bay. During the second phase (July 25-August 15), the crews will be installing seven of the western sites based off of a boat, the Kittiwake. The final phase of the project (August 12-31) will be based out of False Pass, when the crews will install the remaining stations.
UNAVCO recently offered a series of well-attended short courses on processing and using various PBO data, including LiDAR, strainmeter and tiltmeter, and InSAR.
PBO is installing six borehole strainmeters in Yellowstone National Park to aid in understanding ongoing volcanic processes. Two strainmeters were installed in the fall of 2007, another instrument was installed in early July, and three more are being installed in July and August of 2008.
Two GeoEarthScope airborne LiDAR imagery acquisition campaigns were successfully completed in April 2008
In late April 2008, a crew of three field engineers from the Basin and Range and Rocky Mountain regions of PBO conducted a 6000 mile road trip from Salt lake City, UT through the southeastern US and back, and completed the installation of three permanent GPS stations in Arkansas, Tennessee, and North Carolina.
Fifteen hours of tremor per day for three days plus significant GPS displacements in north-west Washington suggests that the 2008 Cascadia Episodic Tremor and Slip (ETS) event is underway (http://www.pnsn.org/WEBICORDER/DEEPTREM/winter2008.html).
High-rate GPS data from the UNAVCO Plate Boundary Observatory (PBO) network, installed in collaboration with the Alaska Volcano Observatory, were analyzed by a group of geophysicists and volcanologists under the lead of Mario Mattia (Istituto Nazionale di Geofisica e Vulcanologia, Catania, Italy) in order to study in detail the deformation and unrest preceding a major eruption of Mt. Augustine volcano (Mattia et al., 2008).
On February 21, 2008 PBOs Siting Outreach Specialist Jayme Margolin gave a talk at the SDSU Brawley Campus entiled EarthScope: Revealing the Earths Secrets.
On Thursday, February 21, 2008, an earthquake occurred in north-central Nevada 10 km ENE of Wells, Nevada, near interstate 80.
December marked the completion of seven borehole strainmeter installations in Canada. The installations were part of the overall PBO EarthScope effort, but focus on regularly occurring Episodic Tremor and Slip (ETS) events best observed in a region from southern Puget Sound to central Vancouver Island. The physical processes, crustal properties, and tectonic environment that give rise to ETDS events are not yet well understood. In the summer of 2005, three instruments were installed at the Pacific Geoscience Centre (PGC) in Sidney, British Columbia, Canada and one instrument was installed at Ucluelet on the west coast of Vancouver Island. In the Fall of 2007 three additional BSM stations were installed at Lake Cowichan (B926), Port Alberni (B927), and Bamfield (B928). The Port Alberni site will share infrastructure with the Neptune project. Borehole strainmeter installations at Port Alberni and Bamfield along with the high-rate real-time continuous GPS stations at both those locations will provide the capability to monitor the propagation of transient signals from offshore and vice versa.
The first processed products from the GeoEarthScope Northern California Airborne LiDAR project were released to the community in December, 2007. Additional products from this vast dataset will be released in the coming months, along with more advanced access and analysis tools, as processing efforts continue. The data are currently available as 1 km^2 tiles of 0.5 m digital elevation models - both unfiltered (all data) and filtered (bare earth) - in ESRI (ArcGIS) binary grid format.
Educational and Outreach (E&O) activities began at PBO sites that have requested E&O involvement. At Sunrise Tree Farm in Philomath, Oregon, several school programs and community presentations were shared. This is a busy time of year for a site with a deep brace GPS monument (P375) that is eager for new educational materials and programs. Two different school groups with about 60 students ranging in age from seven years old to seventeen learned about the theory of plate tectonics, Oregon’s regional landforms and tectonic activity, and then the use of GPS. About 35 teachers, parents, staff members, and the general public also listened to the presentations covering the PBO mission, components of the GPS monument, and more. From their questions and enthusiasm, this site visit proved to be a success.
Plate Boundary Observatory crews installed borehole strainmeters and seismometers at B207 (Madison Junction) and B028 (Lake Junction) in Yellowstone National Park. The installations were a joint effort between EarthScope the National Park Service, USGS, and the University of Utah. We were greatly assisted in the field by National Park Service Employees Hank Heasler (borehole geophysics and geology) and Cheryl Jaworowski (cuttings geology and installation zone selection). Four additional boreholes are planned for installation in the Spring and Summer of 2008.
The PBO installation crews constructed GPS station number 200 in Northern California in October. On October 24, GPS station P660 was completed near Mt Shasta, CA. A deep-drilled monument was constructed at this site, utilizing radio data communications, a three-panel solar system, and an upgraded security system. PBO Northern California finished the month with 201 GPS installations, well ahead of the scheduled mark of 192 installations. This will put the region in good shape to finish the project next year on-schedule.
As of the end of September 2007, the Plate Boundary Observatory installed 708 GPS stations, 44 borehole strainmeters, and three long-baseline laser strainmeters. PBO has now produced 470.5 GB of raw data (single copy, not counting seismic data) in 877,231 data files. PBO has now produced 218.3 GB of seismic data (single copy, miniSEED format). PBO has also now produced a total of 688.8 GB of raw data. All PBO data are publicly available at EarthScope funded data centers. PBO has collected approximately 95.8% of the data that could possibly have been collected over the PBO lifespan. Data not recorded were due to the NetRS failures in 2005 and power failures at the Anza borehole strainmeters in the summer of 2006. No data have been lost to date once they have entered the PBO Data Management System.
Text by Dr. Kevin Furlong, Geosciences Professor at Penn State and Chair of UNAVCO's GeoEarthScope LiDAR Working Group GeoEarthScope is a component of EarthScope that includes the acquisition of aerial and satellite imagery and geochronology. As part of GeoEarthScope, we are working on collecting LiDAR (Light Detection And Ranging) data along major fault zones in the western U.S. and Alaska over the next year. This effort will provide extensive and detailed images of active faults throughout the tectonic plate boundary region on the west coast of North America. Airborne LiDAR is an unparalleled remote sensing technique for generating extremely detailed maps of ground elevation. Because of LiDAR's advantages over previous remote sensing techniques, it is rapidly becoming a key tool in studies of active faulting, landscape processes, and ground deformation.
During the month of August, PBO Permitting made excellent progress on Borehole Strainmeter and GPS permitting. We received 14 new BSM permits including permits for five sites in Yellowstone National Park. In addition, we are making excellent progress on the Mendocino, Mojave, LA Basin, and East Bay Parks (San Francisco) strainmeter permits. These remaining clusters will include several alternate sites for each primary site so that there will be no interruption in drilling if a bad hole is encountered.
Data collection for the GeoEarthScope Northern California LiDAR project concluded in April 2007. Over the course of several weeks, approximately 1400 square kilometers of EarthScope targets were imaged as well as supplementary targets for the USGS and the California PUC. Between this project and the previously conducted B4 project, also funded by NSF, the entire San Andreas fault system, along with many other important adjacent faults and structures, have now been imaged with high resolution airborne LiDAR.
During August of 2007, the Plate Boundary Observatory (PBO) successfully installed four Lily Self Leveling Borehole Tiltmeters on Akutan Volcano, in the central Aleutian Islands of Alaska. All four instruments were collocated with existing PBO Global Positioning Systems (GPS) stations installed on the volcano in 2005. The tiltmeters will aid researchers in detecting and measuring flank deformation associated with future magmatic intrusions of the volcano. All four of the tiltmeters were installed by PBO field crews with helicopter support provided by JL Aviation and logistical support from the Trident Seafood Corporation, the City of Akutan, and the Akutan Corporation. Lack of roads and drivable trails on the remote volcanic island required that all drilling equipment be transported to each site from the village of Akutan by slinging gear beneath the helicopter and with internal loads. Despite poor weather conditions during the installation, all four tiltmeters were installed in 9 days on the volcano in addition to completing maintenance on the existing GPS stations elsewhere on the volcano.
Construction of the final pair of PBO long baseline (laser) strainmeters, near Cholame, California, is making impressive progress. These 400-meter long instruments are being sited over a region of recently discovered seismic tremor activity. The instruments will also detect strain changes in the Parkfield area to the north, and on the locked section of the San Andreas Fault nearby, which last ruptured 150 years ago. The first of the PBO longbase (laser) strainmeters, DHL2, is located at the other end of the southern San Andreas Fault, some 500 km distant; that highly strained segment of the fault has not ruptured in over 300 years and is estimated to be supporting over seven meters of slip-deficit. The photograph shows the endpoints of the East-West instrument during the drilling of the optical-fiber anchoring systems which are emplaced in paired 25 meter deep boreholes. When the strainmeter construction is completed there will be small buildings at each end for the optics and electronics, with an above-ground evacuated pipe providing a stable pathway for laser light running between them.
In July and early August EarthScope Plate Boundary Observatory field crews installed 3 borehole strainmeter stations surrounding Mt. St Helens. Crews installed stations at station B202 (Windy Ridge), B203 (Quarry), and B204 (Marble Mountain). Each installation consists of a borehole strainmeter installed at ~800 ft deep, a 3 component seismometer located just above the strainmeter, and a tiltmeter will be installed ~ 100 ft below the surface. The final station in the cluster, B201, is nearing completion and will be installed in the early fall.
As of May 31, nine students were hired for the 2007 PBO Summer Student Program. From June to September, these students will be working with PBO installation crews in all of the PBO regions. The program is intended to get young people interested in the geosciences by developing technical and professional skills while learning about the science and construction of EarthScope. Many of the students are on their second season in the program, which significantly adds to the productivity and efficiency of the installation crews.
PBO will install 5 additional stations in the Eastern United States, to complement the eleven existing GPS stations collocated at USArray sites.
On 12pm, May 17, 2007 PST the San Juan Grade borehole strainmeter, part of the San Juan Batista array, was installed. This installation, the 33rd of the project, was a milestone for the project. This installation included all new drilling methods and a critical replacement grout, both elements critical to the success of the project.
Greg Anderson (PBO Data Products Manager) and David Mencin (PBO Strainmeter Operations Manager) convened a special session on Integrated Borehole Geodetic and Seismic Networks: A Developing Tool for Earth Science during the 2007 Annual Meeting of the Seismological Society of America. On 11 April 2007, scientists gathered for a full day of talks and posters covering topics including episodic tremor and slip along subduction zones and strike-slip faults; use of borehole seismic data for earthquake source scaling, improving catalogs, and the like; calibration and presentation of data; and operations of current networks around the world. The presenters and attendees -- as many as 100 at a time -- came from four continents, demonstrating the keen scientific interest in borehole seismic and geodetic data. This session was an important step in the expansion of the borehole science community, bringing in a diverse audience and demonstrating the value of EarthScope borehole data in better understanding of a wide range of fundamental Earth science questions.
Data acquisition for the GeoEarthScope Northern California LiDAR project was completed successfully in April 2007. Over the course of several weeks approximately 1400 square kilometers of EarthScope targets were imaged, as well as supplementary targets for the USGS and the California PUC. Between this project and the previously conducted B4 project, also funded by NSF, the entire San Andreas fault system has now been imaged with high resolution airborne LiDAR, along with many other important faults and structures. This represents a major milestone for GeoEarthScope and a significant achievement for the entire EarthScope project and community.
Teachers from around the country participated in a four-hour workshop given at the EarthScope National Meeting. Teachers learned about EarthScope, explored the Earth Structure through a hands on activity (shown: Ricardo Flores from Antelope Valley High School), discussed fault creep by using the earthquake machine, and investigated episodic tremor and slip in the Pacific Northwest. There was also a hands-on activity using GPS data from the Plate Boundary Observatory.
The PBO Alaska Regional Office installed the first of four Permafrost GPS monuments planned for Alaska in the city Kotzebue on March 7th 2007. Kotzebue is located on the northwest portion of the Baldwin Peninsula on Kotzebue Sound in Northwest Alaska. The permafrost monument is a new one of a kind monument that was designed by Duane Miller and Associates LLC for UNAVCO using a thermopile manufactured by Arctic Foundation, Inc. to build and maintain a stable GPS monument in Arctic areas with permafrost subject to seasonal freeze thaw cycles. The station was designed to replace the traditional Deep Drilled Braced Monument (DDBM) commonly used by UNAVCO, Inc in unfrozen conditions. A standard DDBM would not have remained stable in permafrost because the angled legs of the DDBM would have been subject to extensive vertical frost action forces as the active layer of the permafrost froze and thawed on a seasonal basis. The active layers of the permafrost in the Kotzebue area is typically 3 to 4 feet deep and with the annual freeze thaw cycles and constant movement of the entire ground surface, the legs and entire monument would have permanently deformed in only a few years.
A new deep braced GPS monument was completed on February 14th at the Newport Municipal Airport in western Oregon to replace the existing GPS monument (NEWP) that had been installed in June of 1996, by hand digging down to a meter, and then pounding rebar to approximately 1/2 meter. During a visit in May of 2006, it was found that the monument was deeply rusted. This location is an important site for monitoring activity related to the Cascadia Subduction zone. Both the old station (NEWP) and P367 have been running simultaneously since February 15th of this month.
The installation of strainmeter B026 was filmed for a National Geographic special "Earth Shocks" during the week of March 26th. Wade Johnson, Tim Dittmann, Alan Stroeve, James Stair, Michael Gottlieb, Sarah Venator and Andy Tiedmann of PBO were present and Herb Dragert of the Pacific Geosciences Center and a member of the PBOSC was present as well. The special will be one hour long and aired on the National Geographic television channel. PBO instrumentation, especially strainmeters, will be displayed along with their role in identifying and understanding the episodic tremors in the PNW.
The Pacific Northwest Seismic Network reports that strong tremor began in the central-south Puget Sound Jan 13, 2007 and that it is migrating in a north-northwest direction. PBO has installed 13 borehole strainmeters and seismometers in the region. To view strain data recorded by each of PBO's Pacific Northwest strainmeter network visit the Strainmeter Data Product Page.
The Rio Grande Rift project continues to be the main focus of the PBO Campaign support group, with four more monuments having been installed in early December. The network will consist of 25 semi-permanent GPS stations in Colorado and New Mexico, of which 21 have now been completed. Project PI's Anne Sheehan and Steve Nerem of the University of Colorado, Tony Lowry of Utah State, and Mousumi Roy of the University of New Mexico will analyze data acquired by these stations over the next five years to determine velocity and tectonic style associated with the Rift.
Numerous science, facility construction, and education and outreach papers were presented at the Fall AGU meeting. As we move into year four of the construction phase of the MREFC, it is highly encouraging to see the science community using and interpreting PBO data and data products to resolve key EarthScope science goals. PBO staff participated in numerous talks and posters outlining the state of the construction and data management activities, and more importantly to garner feedback from the science community on how to improve data and information access, education and outreach, and construction processes and procedure. The following are a summary of science, education and outreach, and facility construction abstracts.
The next Cascadia Episodic Tremor and Slip Event is predicted to begin between late October 2006 and late January 2007 (95% confidence limits). A few bursts of tremor lasting three to four days have been reported by the Pacific Northwest Seismic Network and the Pacific Geoscience Centre since November 8, 2006 but the expected event, usually associated with 10 to 20 days of continuous tremor, has not happened yet. Strain anomalies have been noted beginning November 4, 2006 but these could well be caused by the record rainfall which occurred in the area at that time. PBO continues to monitor the Olympic Peninsula strainmeters for any transients that may be associated with the ETS events. To view strain data recorded at each of PBO's Olympic Peninsula strainmeter network visit the Olympic Peninsula borehole strainmeter home pages.
During the period spanning October 10th through November 2nd, five BSM installations were completed by a single fully staffed installation team. These installations included down-hole instrumentation, up-hole electronics, and communications systems installed with data flowing to the EarthScope archive. Sites installed include, B073 Varian 1, B075 Flengte Flats, B076 Donna Lee, B078 Gold Hill and B079 Jack Canyon. These installations complete the first phase of installations in Parkfield. The Varian 2 hole was abandoned due to unsuitable geology. Drilling of the boreholes began in September 2006. These installations represent a significant milestone in achieving a sustainable installation rate of three sites per month, including logistics, with a single installation team.
AV18 was started and completed in one day (Sunday) just before Karl Feaux and Austin Baldwin arrived at the island on a float plane. On Monday the crews started and completed AV16, a site located on the west island across the lagoon from base camp. Meanwhile, two potential locations for GPS monuments were found during reconnaissance. Excellent weather and clear skies allowed crews to work continuously through both days.
UNAVCO field crews have returned to Augustine Volcano to install five permanent EarthScope GPS stations. These stations will add to the data footprint from those installed by UNAVCO exactly two years ago in 2004. Since then, Augustine has experienced some significant activity starting this year in mid-January with a series of explosions and erupts, sending plumes of ash more than 40,000 feet into the air. Two of the five EarthScope GPS stations were completely destroyed, however not before capturing priceless data from the volcano's fierce rumblings.
UNAVCO participated in an "Education Day" at the Pathfinder Ranch Science and Outdoor Education School in Mountain Center, California, on July 27, 2006. Pathfinder Ranch is hosting two of the eight EarthScope borehole strainmeters in the Anza region to study the area between the San Andreas Fault and the San Jacinto Fault.
On July 21, 2006, the 400th permanent GPS station of the EarthScope Plate Boundary Observatory was installed. Near the midway point of completing 852 installs by September 30, 2008, this milestone reinforces the dedication and vigor of the community and staff involved in completing this 5-year construction phase.
All three GeoEarthScope working groups - LiDAR, InSAR and Geochronology - have now met at UNAVCO. These working groups are charged with identifying and prioritizing potential targets for airborne and satellite imagery and geochronology acquisitions through GeoEarthScope. Each group will submit a report to UNAVCO by August 31, 2006. These group reports will be subsequently reviewed and an overall GeoEarthScope acquisition plan based upon the three reports will be presented at open forums during GSA in October and AGU in December.
The Plate Boundary Observatory is installing a cluster of seven borehole strainmeter instruments in the Anza region in southern California. This area is of geophysical interest because of its position between two major faults: the San Andreas Fault and the San Jacinto Fault. UNAVCO created a video to update the community on the type of measurements the strainmeters will record and to show the complicated process required to successfully install a strainmeter once the borehole has been drilled. To access the video, please click on the link below. Requests for copies can be sent to Krista Barbour. » Download Video
Congratulations to the UNAVCO Richmond, California office for completing the 100th Plate Boundary Observatory GPS station installation in Northern California on June 2, 2006. Short-drilled GPS station P183 was installed on Bodega Head, a spit off of Bodega Bay, California. Bodega Head is one of the few places north of San Francisco where a GPS station can be located on the west side of the San Andreas Fault. Several years ago Bodega Bay was considered as a location for a nuclear power plant. Fortunately, once they discovered the fault line underneath Bodega Bay they decided to look elsewhere.
The GeoEarthScope LiDAR working group met at UNAVCO on May 24-25, 2006 to identify and prioritize targets for Airborne Laser Swath Mapping (ALSM) acquisition for GeoEarthScope, the geologic component of the NSF funded EarthScope project. The participants identified numerous data acquisition targets in the EarthScope footprint, and the working group's final report will be submitted to UNAVCO and NSF in mid June. The working group's recommendations will be reviewed by the National Science Foundation, and once approved, UNAVCO will oversee the acquisition, data processing and archiving of ALSM data. Working group members include Ron Bruhn (Univ. of Utah), Doug Burbank (UCSB), James Dolan (USC), Kevin Furlong (Penn State, Chair), John Oldow (Univ. of Idaho), Carol Prentice (USGS, ex officio), Charley Rubin (CWU), Steve Wesnousky (UNR) and Brian Wernicke (Caltech).
UNAVCO welcomes Eric Calais as the new UNAVCO Chairman of the Board and PBO Representative on the EarthScope Facility Executive Committee (EFEC). Eric is an Associate Professor of Geophysics at Purdue University and has been closely involved with UNAVCO for several years. We look forward to several more years of working with Eric and benefiting from his dedication to the growth and success of UNAVCO. Eric is replacing Paul Silver (Carnegie Institute of Washington) in both of these positions. Paul has been a PBO EFEC Representative since 2003 and UNAVCO Board Chair since 2004. UNAVCO would like to thank Paul for his dedication and strong leadership to UNAVCO and the EarthScope Project. His support has been paramount in promoting the growth of both organizations. Paul continues on the Board of Directors as Vice-Chair.
UNIVISION, a leading Spanish television network in the United States and Mexico contacted PBO to conduct interviews and gather footage for segments of a television show called Aquí y Ahora. Part of the segments covers what the scientific community is doing to better understand geodetic hazards (such as earthquakes) on the west coast and what is being done to better prepare for such emergencies.
The installation of the first ten PBO borehole strainmeters (BSMs) represents a major accomplishment for the EarthScope community. These instruments provide high resolution geodetic data spanning the frequency band from seismic data to GPS data, giving scientists good insight into processes with durations of hours to weeks. For example, strain associated with a Cascadia episodic slip event in September, 2005, was recorded by at least one and probably several of the BSMs. To date there are eight months of data available from the first four PBO BSMs, and up to six months of data from five other instruments.
By Sarah K. Thompson, Daniel J. Johnson, and Richard A. Bennett Background The regular occurrence of episodic deformation transients in Cascadia provides an ideal opportunity to study processes occurring within subduction zones capable of producing great megathrust earthquakes. GPS provides a unique observation of these events, during which the lower part of the subduction interface releases strain without detectable seismic shaking. Slow slip events last roughly 10 days and occur approximately every 14 months (Dragert et al. 2001; Miller et al. 2002). The surface expression of the transient deformation, which is opposite in direction to the long-term eastward interseismic deformation, amounts to ~4-8 mm and is interpreted to represent ~20 mm of westward displacement along the interface over an area of 50 by 300 km (Dragert et al. 2001).
One of the key goals of the NSF-funded EarthScope Plate Boundary Observatory (PBO) project, capturing deformation related to magmatic processes along the Aleutian volcanic arc, is being met in dramatic fashion on Augustine Volcano, Alaska.
PBO and SAFOD, two of three elements of the EarthScope Project, combined efforts to permit and install a deep-drill braced monument GPS station near the SAFOD borehole in Parkfield, CA. Data from this GPS station will compliment the data set from the SAFOD drill hole. Additionally, this station will measure post seismic deformation following the September 2004 seismic event in Parkfield, CA.
A GPS site located on the Promontory in Yellowstone National Park (P709) was successfully completed during the last week in September. The Promontory is a peninsula between the South and Southeast Arms of Yellowstone Lake. Because of the location and accessibility, this site has been thought from the beginning to be one of the most difficult YNP sites to permit and install.
UNAVCO is pleased to announce a significant milestone for the NSF-funded EarthScope project and the larger geodetic community: processed geodetic data products are now available from the Plate Boundary Observatory. With this milestone, the community now has, for the first time, free and open access to a full suite of geodetic data products spanning the frequency spectrum from periods of seconds to years, and produced using fully documented, community vetted methods. Processed GPS products are produced by Analysis Centers at Central Washington University and the University of California, Berkeley and the Analysis Center Coordinator at the Massachusetts Institute of Technology. The products include GPS solutions in standard SINEX format, as well as station position time series and network velocity fields. All these products, and the raw data from which they are derived, are stored at the UNAVCO Facility GPS archive. The raw data and data products are documented and available from the PBO GPS Products web page at http://pboweb.unavco.org/?pageid=88.
The Plate Boundary Observatory has met another significant milestone in the MREFC phase. On September 12, 2005, PBO engineers Mike Hasting and Peter Gray completed the first co-located borehole strainmeter (BSM) and GPS site. The combination of these two instruments at one site will provide comprehensive coverage of deformation from 100ths of seconds to 10s of years by collocating seismometer, borehole strainmeter, pore pressure monitor, and precision GPS sensors at a single site.
We, along with our partners at the University of California, San Diego (UCSD), the IRIS Data Management Center (IRIS DMC), and the Northern California Earthquake Data Center (NCEDC) at the University of California, Berkeley, are pleased to announce that the first raw strainmeter data from the EarthScope Plate Boundary Observatory are now available.
Since early August, PBO strainmeter crews have been working on Vancouver Island to create a network of borehole strainmeters. As of this writing, four new boreholes have been drilled on the Island, three at the Pacific Geoscience Center (PGC) located in Sidney, and one at the Ucluelet Coastguard Station on the western side of the Island. Unlike the previous strainmeter installs, a challenge at these Canadian sites has been to contain and remove all liquid and solid matter, or "cuttings," extracted during the drilling operation. This process is required by the site permits so as not to contaminate the local bays with silt from the cuttings.
With 10 GPS stations recently installed across the northern Olympic Peninsula, the campaign GPS deployment to monitor the imminent Cascadia episodic tremor and slip event is underway. On August 4, 2005, permitting was completed for GPS installations in Olympic National Park where the bulk of the sites on the peninsula will be located. Since then, four GPS stations have been installed in the park and another 20 GPS units are scheduled for deployment in the Olympic Peninsula and Puget Sound regions in upcoming weeks.
With PBO reconnaissance and installation in full swing for the summer, UNAVCO has hired several Student Assistants on field crews in four of the six regions. One Summer Student Assistant has also been hired to help with data management at UNAVCO headquarters in Boulder, CO. These summer jobs are part of UNAVCO's efforts to broaden participation in science by including students in UNAVCO, PBO, and EarthScope activities.
Based in Montana for the summer, the Rocky Mountain regional staff is working in the Yellowstone/Teton area to install GPS monuments, set up a communications network, and perform reconnaissance and permitting activities throughout Montana, Wyoming, and Idaho. There are currently eight sites scheduled to be installed in Yellowstone National Park over the next several months: five monument installations this summer and three installed next summer (2006). So far, six of the eight sites have been identified and permitted. Additionally, a few sites just outside of the park are part of the Yellowstone monitoring network.
The PBO crews on Akutan have reached their goal of installing eight continuous GPS stations as of July 5th, a full week and 25 hours of helicopter time ahead of the project schedule. The PBO crews have persevered through difficult weather and challenging environment. The following are details of the PBO crew member experiences since July 26, 2005 through July 5, 2005 provided by Mike Jackson, PBO Director and leader of the Akutan installations.
PBO Rocky Mountain Regional Engineer Steve Borenstein and Field Engineer David Kasmer loaded up their truck and trailer with over a ton of GPS equipment and drove from their office in Boulder, Colorado to Bozeman, Montana, where they will remain for the duration of the summer. Steve, David, and Field Engineer Tom Lyman will install 12 (8 shallow-drilled and 4 deep-drilled) GPS monuments and set up a communications network in the Yellowstone/Teton region. Concurrently, the crew is working on reconnaissance and permitting activities throughout Montana, Wyoming, and Idaho.
PBO, with our partners at the Alaska Volcano Observatory, has begun to install continuous GPS stations on the third volcano in the PBO network: Akutan, a 1300-meter-tall composite stratovolcano located in the Aleutian Islands about 1200 km SW of Anchorage, Alaska. Akutan was chosen as a target for PBO GPS studies because it is one of the most active volcanoes in the Aleutians, with 30 recorded historic eruptions including one in 1992, as well as intense ground deformation related to shallow dike intrusion in 1996. Akutan also has diverse magmatic systems, ranging from basalt through rhyolite, though most of its lavas are andesitic. PBO’s GPS studies of Akutan will help us better understand magma movements beneath plate margin volcanoes in a subduction zone, the dynamics of eruptive and intrusive processes, and help scientists improve eruption prediction and volcano hazards mitigation. PBO plans to install eight continuous GPS stations on Akutan during the next few weeks.
Excited to complete the final installation steps of the first EarthScope borehole strainmeter, the PBO strainmeter crew began work early on Friday morning. After connecting the AC power at the enclosure, the engineers interfaced the strainmeter and other instruments with the power and opto-isolation systems. Following that, engineers assembled the satellite communications system (VSAT), connected it to the instrumentation, and began testing seismic and strainmeter data communications. Hurray!
A significant milestone has been reached for the Plate Boundary Observatory component of the EarthScope project. The first long-baseline laser strainmeter installation was completed on June 1, 2005. Since then, the strainmeter has successfully returned data to the Plate Boundary Observatory Data Collection Center located in Boulder, Colorado.
Upon arriving at the site, we found good news: the concrete successfully blocked up the 6-inch casing, as the artesian water flowing out of the borehole now only comes out of the 2-inch PVC that holds the seismometer. From the opening of the borehole, crews measured 322 feet down to the top of the concrete. This area will be left open to allow the potential for other instruments to be installed in the future.
Flush with the successful installation of the first PBO borehole strainmeter and seismometer, crews continued to finish work at the Hoko Falls station. The next steps included pouring layers of cement and sand into the borehole. First, 20-foot sections of 1-inch PVC were inserted into the borehole to a depth of 530 feet. After the field crew tested the seismometer and strainmeter instruments one last time for peace of mind, they lined up 94-pound cement bags and large buckets of water beside the mixer. Because of the size of the hopper, several batches of cement had to be mixed, making the timing of the operation and the water and cement proportions critical. As the hopper filled with cement, the cement was pumped under high pressure through a line that attaches directly to the top piece of PVC. Cement spilled out the bottom of the 530 feet of PVC and began to fill the borehole. After mixing and pumping over 11 bags of cement, the crewmembers removed the PVC sections from the borehole and thoroughly cleaned all of the equipment to remove any remaining cement that would dry and could possibly cause damage to the mixer or plug up the PVC sections.
Crews arrived at the Hoko borehole site first thing Tuesday morning ready to begin the testing of the strainmeter and continue preparing for the installation. First, crews tested the “trip mechanism” - a device that is used to dispense the grout once the 30’ dump bailer touches the bottom of the borehole. A couple of dry runs to the bottom of the borehole proved successful activation of the trip mechanism upon reaching the floor of the hole.
PBO Strainmeter Engineers Bob Mueller, Mike Hasting, and Wade Johnson have been anxiously waiting for this week to arrive. After detecting unwanted noise while testing the first PBO borehole strainmeter during the first scheduled installation in March 2005, crews had to delay installation for “Unit 0” until the problem was identified and repaired. Once the unit was returned to the manufacturer’s labs in Australia, a small amount of condensation was detected in the instrument and was the culprit causing the extra noise. Since then, the problem has been repaired and the strainmeter sent back to the United States for this second installation attempt.
PBO's Northern California region just finished a number of GPS installations throughout the East Bay regional parks (EBRP). Bulk permits for 10 GPS sites were obtained from EBRP and eight stations have been installed, three of which are deep drill braced monuments.
EarthScope held their first National Meeting on March 28-31, 2005 at the Tamaya Resort in Santa Ana Pueblo, New Mexico. The meeting began with presentations given by the EarthScope Organizing Committee on State of EarthScope – Science, Community, and Facility, and a keynote talk given by special guest Robert Smith, from the University of Utah, entitled “Yellowstone Hotspot: Integrative Research and Complimentary Goals of EarthScope.” The following days included several presentations on Science, Education, and Outreach, and a conclusion presentation on The EarthScope Vision.
Crews woke up to drizzling rain and cloudy skies this morning. Despite small openings in the sky, the wet weather persisted intermittently throughout the day. As the installation steps continued to be refined through "dry runs" outside the borehole, testing continued on the strainmeter. Inside the enclosed walls of a large truck to protect from them from the rain, PBO personnel continued to learn the workings and test results of the instrument. Unfortunately, unexplained noise appeared in the test results, and crews spent the rest of the afternoon trying to diagnose the problem.
Crews met early this morning to begin working on the installation process. Another unusually sunny day in Sekiu, crews started out preparing the grouting pump and mixer. Test batches of grout were mixed to find the ideal consistency for the strainmeter install and to become familiar with the window of time available before the grout sets.
After many months of planning and preparing, today marks the beginning of a new stage in the Plate Boundary Observatory project: installation of the first PBO strainmeter instrument.
The Transform Site Selection Working Group met in Sacramento, California, for a one-day meeting on February 18, 2005. Led by Gerald Bawden, chair of the working group, the meeting adjourned at the end of the day with comprehensive station siting recommendations for the Northern and Southern California regions.
A well defined and timely action plan recommendation is the result of a two-day Extension Working Group meeting held in Tucson, Arizona. Led by Rick Bennett, chair of the working group, the committee discussed the prioritization and possible re-location of planned GPS sites in the Basin and Range region. Made up of scientists familiar with the Basin & Range region, the group discussed where stations should be installed to capture the most significant and scientifically relevant data to best meet the EarthScope project goals. A formal statement summarizing the committee's recommendations will be submitted to PBO management. This document will be available online after it is released.
The morning of January 18th 2005 kicked off the next step in the PBO Strainmeter installation process: coring of the drilled boreholes. Coring began at the Goldbeck site, one of the eight boreholes drilled in the Pacific Northwest region. This next step is essential in determining whether or not the chosen borehole location is made up of competent enough rock to host a strainmeter instrument. The coring process involves drilling through the bottom of the borehole using a special drill bit attached to a 10-foot barrel that captures solid cylinders of rock. These sections of rock are pulled out of the borehole and closely inspected to understand the composition of the borehole at that depth. While some mechanical fractures may occur from the coring process itself, crews are specifically looking for an 8-12-foot section of core that does not contain any evidence of natural fractures. Oxidation and slicken sides in the core can be an indication of a natural fracture. On average it takes about 3 days to complete the coring of one borehole. Approximately 30 feet of core is extracted each day, drilling at a penetration rate of about 1.5 inches per minute.
Members of the Magmatic Systems Working Group convened in Vancouver, WA on January 18, 2005 to discuss scientific priorities for this years upcoming strainmeter and GPS installations located on and around volcanoes and calderas. The group meets once per year to advise PBO on science priorities and provide specific recommendations for station relocations. This year the PBO working group used the USGS Cascades Volcano Observatory facilities to hold the all-day meeting. Site selection and relocation issues were discussed for the Alaska (Aleutians), Rocky Mountain (Yellowstone), Pacific Northwest (Cascades volcanoes), Northern California (Mt. Shasta and Medicine Lake), and Southern California (Long Valley) regions. Committee members discussed recent volcanic unrest combined with existing and planned infrastructure.
Last Friday morning, the drillers arrived at the site early to prepare for the cement truck. Section by section, the drill rig pipe was put back together and inserted into the borehole until reaching the bottom. Once in place, the drillers connected the piping to the float shoe which was welded onto the piece of casing resting at the bottom of the hole.
Hurray - it`s done! Crews completed the drilling for the first of eight strainmeter boreholes in the PNW.
BRRRRR! Crews woke up to temperatures below freezing, making it hard to roll out of bed and get working in the chilly weather. Regardless, activity at the site began at the usual time of 7am by taking another depth measurement of the borehole. Due to some soft settling of materials at the bottom of the hole, the hole depth measured 506 feet. The big mission today: install enough 6-inch casing to line the entire borehole from bottom to top.
Day number three of the BSM activity at Clark West continues. Crews are thankful for the beautiful morning weather, sunny and clear skies with temperatures in the fifties. While waiting for the loggers to arrive from Seattle, WA, people kept busy around the work site moving rock and piles of cuttings, preparing casing, and bagging samples. Overnight, water had filled the majority of the hole, stopping at just 31 feet below the ground surface. By 11am, the logging crew from Golder Associates were on site and ready to begin a series of four different logging tests. Each test takes quite a bit of time, having to lower the instrument to the bottom of the drill hole and slowly pull it up to the top, continuously taking measurements along the way.
Last night a cold front came in, dumping almost an inch of rain at the drill site. Although the rain had stopped by the time everyone arrived at the drill site at AM, the temperature had fallen to a cold and damp 40 degrees.
After a year of planning and organizing, today marks the onset of drilling for the first of 175 strainmeters. PBO is installing a network of state-of-the-art strainmeter instruments. The strainmeters use a mechanical extensometers and very sensitive displacement transducers to measure extension in three directions across a borehole. Sensitive enough to easily detect solid earth tides, observed changes in strain will enable scientists to monitor tectonic deformation between the Pacific and North America plates. To move the strainmeters away from surface sources of noise, each strainmeter is installed in a 600` deep borehole. Borehole drilling is done in two stages. Stage 1 involves mobilizing a drill rig to the site to drill a hole about 500` deep. The most desirable installation requires a section of unfractured rock. However, even at this depth, competent rock is not assured. Stage 2 is aimed at characterizing the borehole more fully using a wireline coring technique.
It is expected that for each of the 875 PBO GPS stations installed, small modifications will need to be made in order to accommodate the vastly different rock and terrain conditions. Most recently, the PBO Alaska field engineers proved to be masterminds by creating a hybrid of the short and deep drilled braced monument in order to install the instrument at a scientifically critical point in Alaska, important because it is located in close proximity to the Shumagin Gap, an area of the Aleutian subduction zone that has not experienced a large earthquake in over 100 years, quite possibly resulting in the accumulation of large strain that could result in a major earthquake.
By the end of the day Wednesday, the PBO X-Men team finished the majority of the second station, P693. After Jackson and Feaux retrofitted the monument, workers from P697 flew over the crater of the volcano to join in on the P693 installation fun. Once again, a completed swing set was successfully slung over the volcano and dropped at the site. Borenstein and Friesen worked on installing the enclosures and antenna, finishing the installation by dusk.
PBO Director Dr. Mike Jackson and Rocky Mountain Regional Engineer Steve Borenstein hit the road in a flash from Boulder, CO, Sunday morning in response to the unexpected recent activity at Mt. St. Helens. Having spent the previous week gathering emergency response GPS materials, packing up the UNAVCO truck and trailer, and making sure their living wills are up to date, Jackson and Borenstein began driving across the country in a Ford F350 truck making just one stop on the way: to pick up PBO`s Basin & Range Regional Engineer, Greg Hilker, from Salt Lake City, UT.
In response to the recent magnitude 6.0 earthquake, PBO crews from the California offices have spent the last two weeks working hard to install a total of five emergency response GPS stations in Parkfield, CA. Directed by PBO`s Northern California Regional Engineer Brian Coyle, the stations are being installed to expand the network of instrumentation surrounding the portion of the San Andreas Fault that ruptured during the Parkfield Earthquake. Speed is of the essence in order to obtain data from the time period immediately following the slip event. Collected using the highest precision GPS instruments, these data are essential to extending the science community`s understanding of what`s happening to our earth and predicting future fault activity.
Whew ` what an incredible adventure! Those of you who have been following the progress of the Augustine project are aware that the installation and base camp updates suddenly stopped on September 18, 2004. Due to the unpredictability of Mother Nature, our internet connection was cut off when strong winds and rain storms circled Augustine. Starting where we left off, here`s how the rest of the journey continued `
YAY! Yesterday, crews completed volcano station AV05 and mainland station AC27. Charna Meth helped Tom Corbett and Mike Jackson apply finishing touches on the mainland station while Barrett Friesen and Seth Friedly finished AV05. Some of the VIPs rode along in the helicopter to make minor adjustments to a couple of the finished stations. Later in the day the wind was calm enough, a trip to the summit of the volcano was made where Mike Jackson deployed another USGS campaign station. Today, crews will be slinging gear back to base camp from a couple of the stations and applying any necessary final touches to the completed stations.
While high winds kept crews away from mainland site AC27 yesterday, Charna Meth helped as Mike Jackson installed two campaign stations on the volcano for USGS. Winds at AV05 were light enough in the morning to get Karl Feaux, Dave Mencin, Barrett Friesen, and Seth Friedly up to the site working on the installation. Working conditions became rough when the wind picked up, throwing pea-sized rocks into the faces of the crew, and making it difficult to keep equipment and materials from blowing away. By 4:30 p.m., when they were scheduled to be picked up by the helicopter, winds were so heavy that the aircraft was unable to land at AV05.
Yesterday, workers completed about 98% of station AC27. Fortunately the weather was nice, with a little bit of a breeze keeping the mosquitoes away for the majority of the day. Once again the crew was safe from bears, but was joined by a small herd of caribou near the station. Meanwhile, another crew was able to make it up to AV05, finishing about 50% of the installation by the end of the day. Although it was pretty cold up at the top, the skies were mostly clear and sunny.
By the end of Tuesday, three holes were drilled for mainland station AC27, and the hut was slung over and put into place. Heavy winds and frozen rain created hard working conditions for most of the day. We continue to be fortunate enough not to have any bear encounters. While that crew was working on station AC27, Dave Mencin and Steve Borenstein brought more batteries and a repeater for communications to station AV02. The repeater will enable mainland station AC27 to communicate with Homer. A quick stop at AV04 allowed the crew to modify a power connection and hook up grounding rod and wire.
Unfortunately, heavy winds kept the crews at camp for most the day Monday. Flying into the wind, it took the AC27 crew 45 minutes to fly 20 miles over to the mainland from Base Camp. Once near the site, the pilot turned the aircraft around due to strong wind and turbulence, fearing that a return flight to pick the crew up might be too risky. Returning to Base Camp only took 15 minutes since the helicopter was flying with the wind. Unfortunately, it was also too windy to reach AV05, the last volcano station to be installed.
A crew headed over to the mainland yesterday to take a look at the proposed location for AC27. Due to bad bedrock, the site will be moved about a mile south of its originally planned location. Mike Jackson and Ben Pauk circumnavigated the volcano yesterday afternoon to collect metadata from stations. Due to high winds, they were only able to make it to stations AV02 and AV03.
Moving right along! As of end of the day Saturday, crews have completed a total of five out of seven stations. The last two stations to install are AC27 and AV05. AC27 is located on Chenik Mountain in the McNeil River State Game Refuge, and AV05 is located on the northeast side of the volcano at 3500 feet.
Yesterday (Friday, September 10, 2004) was definitely the chilliest day so far; clouds covered the volcano keeping the visibility low. By the end of the day, crews had completed the drilling and set up the swing set for site AV02. Sleet-like rain made it hard for workers to keep dry and warm. Needless to say, everyone was very happy to return to base camp at the end of the day.
Yesterday a crew flew to the Cook Inlet where the AC59 site is located. Overcast skies and rain didn`t stop the crew from getting a good start on the installation. The crew installed all electronics and drilled two holes for the monument. Unfortunately, they encountered highly fractured and weathered rock below the surface of the planned drilling location, making it necessary find a new area to install the monument.
The Augustine project continues to be on schedule. Yesterday, crews finished the installation at site AV04 and came close to completing AV01. Today the weather has changed and clouds are coming down over the volcano. Although it represents a change in plans, it`s hard not to be in awe of the thick, smoky white clouds rolling and billowing over the top of Augustine. The temperature has dropped quite a bit and it looks like it might rain. Because of the clouds the helicopter will not be able to fly up to the AV05 site. Currently a field crew is up at the AV01 site putting the final pieces together and should be finished shortly. A second crew is heading over the main land to work on the Ursus Head site, AC59.
Base camp on Augustine Volcano is fully set up and operating about 60 yards away from the shore on the west side of the volcano. Surrounded by tall, thick brush, we had to clear an area large enough for a helicopter landing pad, base camp kitchen, and sleeping tents. One large weather port is set up to act as the main common area for cooking, eating, and working. Two smaller structures serve as storage room for food and equipment. The Homer internet trailer is set up and camp is now connected to the internet using a Hughes DC powered VSAT system. Field days start at 6:30 AM and finish at about 9:30 PM with helicopters ferrying people on and off the volcano installations sites. Handheld radios are used to communicate between the aircraft, installation sites, and base camp. Satellite phones are used for emergency communications and internet keeps the camp in touch with the world.
Katrin Hafner and Peter Gray (Pacific Northwest Region) were busy during the month of June installing three Deep Drilled Braced Monuments (DDBM) in Washington state. Assisted by Karl Feaux and Steve Borenstein of the PBO Boulder office, all three sites were finished in nine days and have been transmitting data through VSAT or VSAT/radio combination.
February 5th and 6th, 2004: The first PBO deep monument installation at Marshall Field, Boulder, CO.
On December 22, 2003, a magnitude 6.5 earthquake occurred on the Oceanic fault zone in the Santa Lucia Mountains of coastal Central California. The earthquake killed two people and collapsed or severely damaged 40 buildings in the Paso Robles-Templeton area. EarthScope's Plate Boundary Observatory (PBO) Transform Site Selection Committee responded immediately by modifying the GPS station-installation plan to record fault movements following the earthquake. For more information on the EarthScope response to the Paso Robles Earthquake click on the image to the right. For more information on recent earthquakes see the USGS Earthquake Hazards Program web page.