This is a combined (gravimetric/geometric) quasi-geoid model for almost the whole province of Tierra del Fuego, computed by means of the Equivalent Source Technique (EST) and the remove-restore technique. The geodetic reference frame is TDF08. The EIGEN-GL04c global gravity model up to degree and order 200 is used to remove the long wavelength part of the spectrum, while the residual terrain correction is based on the SRTM3 digital elevation model. The integration of gravimetric and GPS/levelling data for the computation of the quasi-geoid model is performed by EST, which is basically an inverse gravimetric problem for the estimation of a proper set of point masses. A cross-validation procedure over a set of height anomalies shows a 5 cm error r.m.s. for most of the Argentine part of the island, with larger errors in the Chilean side (up to about 20 cm). The model is here provided with a spatial resolution of 1.5 km.

The geoid model is provided in ISG format 2.0 (ISG Format Specifications), while the file in its original data format is available at the model ISG webpage.

The International Service for the Geoid (ISG) was founded in 1992 (as International Geoid Service - IGeS) and it is now an official service of the International Association of Geodesy (IAG), under the umbrella of the International Gravity Field Service (IGFS). The main activities of ISG consist in collecting, analysing and redistributing local and regional geoid models, as well as organizing international schools on the geoid determination.