Gravity, Gradiometry

Abstract

Definition and Scope Gravity gradiometry encompasses all manners of measuring the spatial gradients of the gravity vector field. In a broader sense, it includes the techniques for developing and applying gradient models, from both analytic and numerical perspectives, in order to validate gradient sensors, to study geologic bodies, and to test physical theories. Gravity gradiometry has a long and varied history of static (ground-based), shipborne, airborne, and spaceborne measurement systems. This entry includes the mathematical foundations and properties of gradients starting with Newton's law of gravitation. A description of straightforward modeling is followed by a rudimentary measurement error analysis; and the entry concludes with a comprehensive account of measurement systems, as well as some sample applications.