Using Newton's law and geophysical bounds on mass density contrast to ensure consistency between gravity and height data

In this paper we advocate the use of Newton's law of gravitational attracti on to ensure perfect consistency between gravity and height data. Starting with the absolute gravity on the topography we decompose this signal into a number of quantities associated with physics of the system. To model gravi tational attraction from topography we use DTM and Newton's law of gravitat ional attraction. A residual part of the gravity signal is interpreted as i nconsistency between gravity and heights. In the paper we discuss a method by which such inconsistency (at least in principle) can be decomposed into a "gravity error" and a "terrain error". In practice such separation is not possible because the two types of error are nearly 100% correlated. The in consistency can be interpreted as a measure of ambiguity of the gravity-ter rain models which are consistent with a set of measured/interpolated data. We discuss the influence of such ambiguity on the accuracy of the geoid for the investigated area of Jutland, Denmark. (C) 2000 Elsevier Science Ltd. All rights reserved.