GDA94 Technical Manual


Photo: Preparing for the Australian National Network Survey in the Northern Territory - August 1993.

The GDA94 Technical Manual is now available online

Version 2.4 - The latest update to the Manual, December 2014

The Geocentric Datum of Australia Technical Manual has been updated to Version 2.4.

In the 8 years since the Technical Manual was last updated there have been changes to the Australia Fiducial Network (AFN) gazettal values as well as advances in AUSGeoid and the International Terrestrial Reference System and Frame. This version of the GDA94 Technical Manual (v2.4) includes:

  • an update of the copyright statement to reflect ICSM’s Creative Commons Attribution 3.0 Australia Licence;
  • update of the 21 AFN Gazettal coordinate values, as submitted 4 April 2012;
  • refresh of text surrounding the equivalency of GDA94 and WGS84/ITRF;
  • refresh of AUSGeoid text for AUSGeoid09 release;
  • inclusion of GDA94 extent definition;
  • correction of equation transcription errors.

The GDA94 Gazettal values can be found in the GDA94 Technical Manual v2.4.

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Links to Transformation Software

NOTE: Online versions of Vincenty’s and Redfearns Formulae are also available on the Geoscience Australia website. The online calculators provide the same results as the spreadsheets in the Technical Manual.