GRAVIMETRIC GEODESY FREE OF DENSITY ESTIMATES THROUGH ANALYSIS OF DISCREET GRAVITY DATA

摘要

Modern gravimetric geodesy was born in 1854 when Stokes published his formula for an explicit solution of the boundary value problem by the aid of a resolvent. The original study was restricted to a sphere but for over 100 years the geodesists have tried to find the gravity reduction which makes it possible to reduce gravity data from the physical surface of the earth down to a reference sphere (or ellipsoid) in such a way that the actual boundary value problem can be properly solved in an explicit way. Earlier methods of reduction (Rudzky a.o.) made use of guessed or estimated values of the density of all external masses. These methods have failed to solve the boundary value problem because there has been no method of determining the density from measurements at the surface of the earth. (For the determination of low order harmonics the accuracy was found satisfactory.)