The influence of the density of the mass of the Earth's crust by the computation of the orthometric heights

Abstract

In the paper is given the analysis of the difference of the power and the geometrical relation leveling superficial and the vertikal. The influence of the force Earth's gravitation was presented on the results of the leveling are given by geometrical leveling, and about dependence of the results of the leveling on the road of the leveling. In order to be avoided the indefiniteness of the determination of the heights of the points, IAG was been suggested 1954. that the states for the all main leveling traverses they are computing the difference of the power using geopotencial height computed from the results of the measurements of the acceleration of the force Earth's gravitation and of the leveling by the geometrical leveling. Because the geopotencial heights are not convenient to the practical use, they are using the physical heights that are definite on the other way. One of he way is orthometric height, that is obtained by the addition of the orthometric correction to the results of the measurements of the heights difference that are obtained by geometrical leveling. In order to get the orthometric corrections with sufficient acctitude to take into consideration the density of the mass Earth's crust. This is presented on the practical exemplars.

U radu se daje analiza razlike potencijala i geometrijski odnos nivoskih površi i vertikale. Prikazan je uticaj sile Zemljine teže na rezultate nivelanja dobijenih geometrijskim nivelmanom i o zavisnosti rezultata nivelanja od puta nivelanja. Da bi se izbegla neodređenost određivanja visina tačaka, Međunarodna asocijacija za geodeziju je preporučila 1954. g. da države za sve glavne nivelmanske vlakove računaju razliku potencijala korišćenjem geopotencijalnih kota sračunatih iz rezultata merenja ubrzanja sile Zemljine teže i nivelanja geometrijskim nivelmanom. Kako geopotencijalne kote nisu pogodne za praktično korišćenje, koriste se fizičke visine definisane na drugi način. Jedan od načina je ortometrijska visina, koja se dobija dodavanjem ortometrijske korekcije rezultatima merenja visinskih razlika dobijenih geometrijskim nivelmanom. Da bi ortometrijske popravke dobili sa dovoljnom tačnošću mora se uzeti u obzir gustina masa Zemljine kore. Ovo je prikazano na praktičnim primerima.