Ekvipotencialinių paviršių nelygiagretumo įvertinimas

Abstract

Non-parallelity of equipotential surfaces of normal field as well as non-coinciding real and normal gravity field surfaces should be taken into consideration when differences of normal heights of points are determined. Therefore normal corrections are computed for the height differences determined in real gravity field by levelling. Normal gravity field of Helmert and gravity system of Potsdam were used for geodetic and gravity activities in Lithuania after World War II. Normal gravity field GRS 80 was accepted when new coordinate system LKS 94 was introduced in 1994. New gravity system IGSN 71 will be introduced too. Absolute gravity points and Lithuanian gravimetric network (under construction) are used for this purpose.[...].