G. Moreaux et al., Approximation of harmonic covariance functions on the sphere by non-harmonic locally supported functions, J GEODESY, 73(10), 1999, pp. 555-567
Three methods to construct positive definite functions with compact support
for the approximation of general geophysical harmonic covariance functions
are presented. The theoretical background is given and simulations carried
out, for three types of covariance functions associated with the determina
tion of the anomalous gravity potential from gravity anomalies. The results
are compared with those of the finite covariance function of Sanso and Sch
uh (1987).