Accession Number : AD0776225

Title :   Analysis of Deflection-of-the-Vertical Inner-Zone Methods.

Descriptive Note : Special pub.,

Corporate Author : NAVAL OCEANOGRAPHIC OFFICE WASHINGTON D C

Personal Author(s) : Kontis,Angelo L. ; Michlik,Rudolph R. ; Davis,Thomas M.

Report Date : FEB 1974

Pagination or Media Count : 86

Abstract : In the Vening Meinesz method of computing deflection of the vertical, the effect of the region surrounding the computation point (termed the inner zone) is usually determined by some special algorithm. A new method based on the representation of gravity anomalies by a sequence of discrete bicubic surfaces and the integration of these surfaces by the flat-earth approximation is given and compared with three existing inner-zone techniques. These techniques, designed for mean-anomaly cells in the shape of trapezoids are (1) two applications of Fischer's method termed Fischer IZN1 for an inner zone with area of about 4 sq nm, and Fischer IZN2 for an inner-zone with area of about 16 sq nm (2) the standard method, in which the inner-zone cells are treated by the Vening Meinesz formula and (3) the rim method in which the deflection effect of the cells surrounding the inner zone is multiplied by a constant. (Modified author abstract)

Descriptors :   *Gravity, *Geodesy, Anomalies, Algorithms, Numerical methods and procedures

Subject Categories : Geodesy

Distribution Statement : APPROVED FOR PUBLIC RELEASE