These pages contain preliminary results from GPS measurements of the deformation caused by the earthquake process. Here you can also find a results from the Geodolite trilateration measurement program.

USGS GPS data are automatically processed to produce maps of velocity and time series of position for the sites. During the automatic processing, individual stations are treated independently. Results from this automatic processing can be accessed through any of the following three pages:

• North America Map
  Clickable map of North America with links to velocities and time series.

• California-Nevada Map
  Clickable map of California-Nevada with links to velocities and time series.

• Campaign List
  List of Campaigns with links to velocities and time series.
  (Most useful if you know the campaign name of interest. If not, see maps above.)

• QOCA Processing
  Links to campaigns that have been processed in a network mode with the Quasi-Observational Combined Analysis (QOCA) software (Estimating Regional Deformation from a Combination of Space and Terrestrial Geodetic Data, D. Dong, T. A. Herring, and R. W. King, Journal of Geodesy, 72, 200-214, 1998).

• GPS Processing Manual
  A description of the GPS processing system used to produce the results linked above.

• About GPS
  A very brief introduction to GPS and how it is used in earthquake research.

• Geodolite Results
  There are two files accessible: One contains approximate positions for all the stations. The other contains the observed line lengths

• North America Map
  This map shows geodolite station locations across North America.

• California-Nevada Map
  This map shows geodolite station locations across California and Nevada.

• Campaign List
  List of geodolite networks with links to all line lengths measured in each net.
  (Most useful if you know the campaign name of interest. If not, see maps above.)

A collection of published and unpublished Euler Poles for various plates

• Euler Poles