Study of the Shape of the Equipotential Surfaces and the Gravity Anomaly Field in High Elevations

摘要

The aim of the project was to study theoretically and practically the dimensions of the normal equipotential surfaces of the earth's gravity, called spheropotential surfaces, and to study the gravity anomaly field and its effect on the shape of the geopotential surfaces, i.e., the distance and tilt between these two surfaces at different elevations. Such studies have not earlier had much practical significance and, consequently, they have not received sufficient attention. All of these computations are based on the gravity anomaly field at the earth's surface. The better the earth's gravity field is surveyed, the more accurately we can get the quantities necessary for study of the earth's gravity field at different elevations. The formulas used for computation of normal gravity and gravitation with their components and the size and shape of the spheropotential surfaces and the formulas for computation of the gravity field at different elevations are given both for the gravity and the gravitation. By gravitation we mean the attraction of the mass of the flattened earth. When we subtract from gravitation the effect of the centrifugal force, we get gravity. These formulas have been derived in Columbus under this project and under the Cambridge Gravity Project. They are based mostly on the theoretical studies of Dr. Hirvonen. The basic quantities concerning the dimensions of the spheropotential surfaces and the gravity and gravitation with their components are explained later on. The normal and actual gravity and gravitation with their components are computed at the interval of 1 degree from the North Pole to the equator. (Author)