Downward Continuation of Airborne Gravimetry Data by Means of Spherical Radial Basis Functions

The problem of downward continuation of airborne gravimetry data is discussed. Use of spherical radial basis functions (SRBF) to solve this ill-posed problem is proposed. Gravity disturbances observed at flight height are continued downward to disturbing potential. The SRBF method is numerically tested using synthesised data for flight heights 2000 m, 4600 m and 6000 m and grid steps 1 arcmin and 2.5 arcmin in area bounded by colatitudes 40 degrees, 43 degrees and longitudes 153 degrees, 157 degrees (spherical coordinates). The experiments prove that the SRBF method can provide stable and accurate results. Moreover, as a result of this procedure one have an approximator in the form of a linear combination of SRBF which allows to determine the values of different transforms of potential by applying the corresponding operators to this expression.