Crustal deformation in Arizona

We are actively working on this project and as such this web site is constantly seeing new content.  Please check back in for the latest on our work in Arizona.

Contents

Continuous and semi-continuous GPS stations

TNSS

AMTN

Campaign GPS

NGS Federal Base Network Observations

2009 Arizona Campaign

Preliminary Results from Campaign GPS

Stable Monuments

Acknowledgements

The purpose of this project is to monitor crustal deformation in Arizona using GPS geodesy. The three aspects of this project are installing continuous and semi-continuous stations, making first  observations using campaign GPS at stable benchmarks, and re-observing benchmarks using campaign GPS methods. 

 

Continuous and semi-continuous GPS stations

Semi-continuous site looking over tucson. Photograph taken by Jason Ninneman.

Semi-continuous GPS site TNSS and campaign measurement of TUC 1987 benchmark.  Photo is overlooking the east side of Tucson. Photograph by Jason Ninneman.


Currently the UofA Tectonic Geodesy Laboratory is operating two semi-continuous sites. These sites are using Trimble Zephyr antennas as shown above. The data is recorded using Trimble 4000 dual-frequency receivers. The data is continuously downloaded and converted to RINEX using Linux PC's at the recording sites. The monuments are UofA Max mount monuments drilled and set in rock outcrop to a depth of 20 cm.

TNSS - Tucson seismic station

This station is located in the foothills  of the Catalina Mountains. It is collocated with a National Geodetic Survey Federal Base Network Benchmark (TUC 1987). This benchmark has been observed in the past by the NGS and provides a tie to the semi-continuous station. The site is located in close proximity to the Tucson Global Seismic Network station, TUC.

Station TNSS, photograph by Jason Ninneman

AMTN - Tumamoc Hill

This station is located in the foothills of the Tucson Mountains not far from downtown Tucson. It is collocated with a gravity base-station.  The station is at the USGS and UofA Desert Laboratory. 

Station AMTN. Photograph by Jason Ninneman.

 

Campaign GPS

This entails re-observing benchmarks which have been previously observed using GPS.  Due to the small deformation rates in Arizona, resolution of deformation requires a significant amount of time between campaign observations.  These measurements are ongoing.

Observation of NGS benchmarks previously observed for the Federal Base Network

These monuments were observed in Arizona in 1998 and 1999 as part of the NGS Federal Base Network (FBN).  This is an ongoing collaborative project between the University of Arizona and the Arizona Geological Survey to better constrain the crustal deformation signal in the Southern Basin and Range, Colorado Plateau, and its transition zone.

See some preliminary results first presented at the 2009 spring SSA Meeting.

 

 

 

2009 Colorado Plateau Southern Basin and Range GPS Campaign

This campaign included the reobservation of almost 30 benchmarks previously observed as described above.  For most sites, we managed to obtain at least three days of good data.  All in all the campaign was a success.  These data will be processed over the summer and should provide the best resolution images of contemporary crustal deformation occurring in Arizona.

Photographs from our fieldwork.

Many people and institutions have contributed to this work to see the list go to the acknowledgements.

2009 Campaign Observations

Click For Larger Image

Red triangles indicate benchmarks which were observed in 2009.  Orange triangles indicate benchmarks observed in 2008.  Gray triangles represent FBN benchmarks observed multiple times, but not in 2008 or 2009.  Gray squares indicate continuous GPS sites.

First observations of stable monuments

First observations using GPS of existing high stability benchmarks will allow them to be used in the future to assess the deformation field in Arizona. High stability benchmarks are those which have been set securely in bedrock, and are expected to last a very long time. These benchmarks allow this and future projects to use campaign GPS techniques to precisely monitor the deformation kinematics in Arizona.

The following is a list of benchmarks which now have observations.

The data and descriptions for these sites will be posted soon. 

Project Contacts

Acknowledgements

The 2009 Colorado Plateau Southern Basin and Range GPS Campaign could not have been accomplished without the support of many.  Without the help of Arizona Geological Survey contributing vehicle time and gas the project would not have been possible.  The assistance of Allyssa Abbey, Shoba Maraj, Jeri Young, and Phil Pearthreee greatly improved the project.  This campaign was also suppported by a ChevronTexaco Geology Fellowship.  Additional data was also provided by the USGS Grand Canyon Monitoring and Research Center.  This data greatly strengthens this work and is truly appreciated.

Without the help of Jason Ninneman the semi-continuous sites at TNSS and AMTN would not be running continuously.