Because of the impossibility of gravimetric observations on all over the leveled lines, the knowledge of the gravity quantities is still a problem when the subject is, for example, the computation of geopotential numbers. Local Covariance Functions (LCF) were generated from gravity values of Brazilian Institute of Geography and Statistics that were digitized and added to Geodetic Reference Systems and Satellite Altimetry Laboratory (LARAS) geodetic database. This base contains gravimetric and altimetric points provided by IGN (Argentina) too. The LCFs were developed for gravity Bouguer anomalies to points which heights were available and the gravity values were recovered. These points are located on the Brazil-Argentina's border. Studies with polynomial function and Fourier function were tested with ten per cent of points of database reserved to testing and the polynomial fourth degree function showed the best results (about 1 mGal).
Covariance Functions; Least Squares Collocation; Geopotential Numbers
