Accession Number : AD0600670

Title :   DEFLECTIONS OF THE VERTICAL CAUSED BY TOPOGRAPHIC MASSES IN THE NEAREST NEIGHBORHOOD OF THE POINT.

Descriptive Note : Scientific rept. no. 6

Corporate Author : OHIO STATE UNIV RESEARCH FOUNDATION COLUMBUS INST OF GEODESY PHOTOGRAMMETRY AND CARTOGRAPHY

Personal Author(s) : Strang van Hees,G. L.

Report Date : MAR 1964

Pagination or Media Count : 21

Abstract : As known, the deflections of the vertical can be computed by the formulas of Vening Meinesz. Although one has to know the gravity over the whole earth, the influence of the nearest neighborhood of the computation point is the greatest. So, it is very important that a dense gravity survey be carried out around the point. However, this is not always possible, especially in mountainous areas. In that case, it is best to compute the influence of the nearest neighborhood from the topography. In this paper is investigated the order of magnitude of the influence of nearby topography on the deflections of the vertical. The influence is computed for several points for an area with a radius of about 5 km around the point. This shows that the influence of the nearest neighborhood can reach considerable amounts and may never be neglected in mountainous areas. Further formulas are derived for the influence of the central zone on the deflections, assuming that the point lies on a slope. In the last chapter some models are studied in order to get a more general insight about the deflections caused by topography. (Author)

Descriptors :   (*GEODESICS, SURVEYING(GEOGRAPHIC)), TERRAIN, DEFLECTION, GRAVITY, GEOPHYSICS

Distribution Statement : APPROVED FOR PUBLIC RELEASE