• WG4. Geodetic and Gravimetric Networks and Data

Coordination: Helena Ribeiro, DGT
Co-coordination: Rui Fernandes, UBI
Institutions: DGT, IGOT, FCUL, FCUP, UBI, UÉ

Working group oriented to the availability and free distribution of Geodetic and Gravimetric data and products, foccused on the Portuguese and European Networks of Permanent GNSS Stations that support Geosciences.

Aims to continue and improve the access to geodetic data repositories and to establish a connection of GNSS stations to seismic stations for use in studies of the Solid Earth.


  • National C4G GNSS Data Portal [here]

  • National DGT Geodetic Portal [here]
    Includes data from the Portuguese Network of Permanent GNSS Stations (ReNEP), the Tide Network, the National Geodetic Network (RGN), the High Precision Geometrical Leveling Network (RNGAP), and the National Gravimetric Network.

  • European GNSS Products Portal [here]
    In the scope of the EPOS project, various analysis/combination centers have computed time series, velocities and strain rate maps for thousands of stations in Europe that can be downloaded from this portal.

  • Geoid model
    Convert elipsoidal height to ortometric height [here]



  • GLASS [here]
    Software for GNSS Network Management

  • Hector [here]
    Software package for Time-Series Analysis. It can be used to estimate a trend in time series with temporal correlated noise. Examples are changes in temperature, sea level or GNSS derived station position over time.




  • Ocean loading corrections [here]
    For precise GNSS and gravity computations it is necessary to correct for the effect of the ocean tides on position and the Earth’s gravity field. This web-service provides these corrections.

  • Coordinate Transformation [here]


  • GNSS Field Campaigns
    C4G provides GNSS equipment and specialized technicians to carry out geodetic (e.g., tectonic & volcanic) and topographic (e.g., digital terrain models) surveys.

  • Gravimetric Field Campaigns
    C4G provides relative gravimeters, GNSS equipment and specialized technicians to carry out gravity surveys. If requested, the raw observations can be analysed to provide gravity values and Bouguer anomalies.

  • Geodetic Equipment Installation

  • Drone Surveys



  • Field training in GNSS equipment
    (available soon)

Check more TRAINING available via C4G.



  • GNSS
    . Geodetic Systems
    . Topographic Systems
  • Total Stations
  • Gravimeters
  • Drones
    . LiDAR
    . RGB Cameras
  • Accessoires
    . Tripods
    . External Radios

Check more EQUIPMENT available via C4G.