Geodetic



Geodetic Data

The majority of GeoNet's ground deformation data is collected continuously using GNSS (commonly referred to at GPS) receivers and antennas.

GPS/GNSS receivers determine very precisely positions on the surface of the earth. We compute a daily position for each of our stations so we can track the deformation caused by the interaction of the Australian and Pacific tectonic plates. This is our collection of GPS/GNSS-related data resources and tools.

GeoNet continuous GNSS/GPS Site

GeoNet continuous GNSS/GPS Site

GNSS stands for Global Navigation Satellite System, and is the standard generic term for satellite navigation systems that provide positioning information with global coverage. Some examples of GNSS systems are GPS, GLONASS, Galileo and Beidou. The term GPS (*Global Positioning System*) is specific to the United States' GNSS system, which being the first one to become operational, has become popularly synonymous with all satellite positioning systems.

GNSS Time Series Data

Daily time series solutions can be easily obtained using GeoNet's FITS data service. There are lots of example requests for GNSS time series data to either download or make plots.

The coordinates and their formal uncertainties are extracted during the GLOBK run from the combined daily solution files, and converted to (east, north, up) displacement in millimetres with respect to an a priori position and epoch in the ITRF2008 realisation.

The resulting time series have no adjustments made to them, so they may, for example, contain offsets due to earthquakes, offsets due to equipment changes at individual sites, and seasonal (annual and semi-annual) signals due to various causes.

For more information on GNSS processing using GAMIT/GLOBK please see the GNSS Time Series Notes.

GNSS RINEX Data

GeoNet's GPS data are stored in RINEX (Receiver Independent Exchange) format.

Sampling Rates


30-second samples

The full set of 30-second sampling rate GPS/GNSS data are available via anonymous ftp from:

Raw GPS data in RINEX format are in the rinex directory. The GPS mark codes may be viewed on the network maps, and the site locations and operational dates may be found in DELTA.

1-second samples

The last two months of 1-second sampling rate GPS data (for PositioNZ sites only) are available as 15-minute files via anonymous ftp from:

Event related 1- and 0.1-second samples

Note: this service is only available temporarily for access testing.

1- and 0.1-second sampling rate GNSS data are available for download for the days surrounding major geologic events. These data are available in RINEX2 and Trimble proprietary raw formats. Data access is through Amazon Web Service and a guide is provided in high rate GNSS data access. Currently these data are only available temporarily for testing purposes. We welcome all feedback and have created a GitHub ticket for your comments.

File Formats


RINEX

A description of RINEX file format may be found at the IGS, International GNSS Service website.

There are two forms of Rinex data available on our ftp site.

RINEX 2 files are in available for all sites but this format only includes tracking for GPS and GLONASS constellations. These files are in Hatanaka-compressed format, with a filename extension like .YYd.Z, where YY is the 2-digit year. Tools for converting Hatanaka-compressed RINEX to standard RINEX (filename extension .YYo) can be found at http://terras.gsi.go.jp/ja/crx2rnx.

RINEX 3 files are available for stations that are capable of tracking all GNSS constellations. These files are in Hatanaka and gzip compressed format (extension crx.gz). RINEX 3 file names follow the convention explained in the IGS Rinex 3 format document.

GNSS Station Metadata

GeoNet's network map can be used to investigate the distribution of GNSS stations.

Station metadata in XML format


Full mark metadata for an individual site: http://magma.geonet.org.nz/services/gps/reception?markCode=taup

Change the markCode suffix to view each different site. In this example, markCode=taup returns station information for the Taupo continuous GPS station TAUP.

Station metadata in IGS format


Station metadata are also provided following the International GNSS Service formats:

Site logs and XML files are available on the GeoNet ftp site.

Station metadata in Gamit/GlobK station.info format


Site equipment setup file that can be used for GNSS processing with Gamit/GlobK is also available on the GeoNet ftp site