Datum Transformations Geodetic Technical Reports

This is an index of Datum Transformations online Geodesy's Technical Papers either published in journals or presented by Geoscience Australia staff at recent meetings and conferences. Other category titles also available from the list below.

• Datum Transformations

• Antarctica
• Global Positioning System (GPS)
• Local Ties
• Satellite Laser Ranging (SLR)
• Very Long Baseline Interferometry (VLBI)
• General

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Datum Transformations

• TITLE: ITRF to GDA Coordinate Transformations [PDF_280k]
  Date: February 2004
  Author: John Dawson & Jim Steed
  Summary: This document provides a practical solution to the transformation of International Terrestrial Reference Frame (ITRF) coordinates into GDA94 coordinates. GDA94 is coordinate datum based on ITRF92 at the fixed epoch of 1994.0. ITRF coordinates will in general differ from GDA94 coordinates for two main reasons, namely tectonic motion of the Australian landmass and reference frame differences. Since 2 December 2001 all International GPS Service (IGS) Products are aligned to ITRF2000. Users transforming coordinates derived from IGS products after 2 December 2001 are provided with additional high quality transformation parameters that are referred to as ITRF2000(IGS). This document provides the 14-Parameter transformations from ITRF2000, ITRF2000(IGS), ITRF97 and ITRF96 to GDA94, and supersedes versions 31.08.2001 and 02.12.2002 of the same title.
  
• TITLE: WGS84 and the Geocentric Datum of Australia 1994 [PDF_108k]
  Forum: IONS GPS 2000
  Location: Salt Lake City, Utah USA
  Date: 25-29 September, 2000
  Author: Jim Steed & Geoff Luton
  Summary: The Geocentric Datum of Australia 1994 (GDA94) is based on the International Terrestrial Reference Frame 1992 (ITRF92) positions at 1st January 1994, computed for the eight Australian Fiducial Network (AFN) sites. GDA94 replaces the former Australian Geodetic Datum (AGD) and was developed to be directly compatible with the Global Positioning System (GPS). However, the relationship between GDA94 and WGS84 is subject to ongoing assessment. In 1993 the National Imagery and Mapping Agency (NIMA) used their GASP software (Malys et al, 1993) to compute WGS84 positions for nineteen Australian sites, five of which are part of the AFN. In 1999 a similar exercise was repeated using data from the eight AFN sites that now form part of the Australian Regional GPS Network (ARGN). These WGS84 positions have been compared with the equivalent GDA94 positions and recently computed ITRF positions and have been used to compute transformation parameters between these reference frames.
  

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