The South American Datum (SAD) is a regional historical geodetic datum for South America.
The most common version was established in 1969 (SAD69), as adopted by the Pan American Institute of Geography and History.
[1] It uses as reference ellipsoid the Geodetic Reference System 1967 (GRS-67), recommended by the International Union of Geodesy and Geophysics in Lucerne in 1967.
[2] This ellipsoid acquired topocentric orientation defined at the astrogeodetic vertex Chuá, in the municipality of Uberaba, Brazil.
[3][4] This datum was subsequently adopted by many South American countries, including the earlier Brazilian Geodetic System (Sistema Geodésico Brasileiro - SGB).