The Gravsat Signal over Tectonic Features

Wagner, CA, Sandwell DT.  1984.  The Gravsat Signal over Tectonic Features. Journal of Geophysical Research. 89:4419-4426.


The range rate between two close gravitational satellites (GRAVSAT) in low earth orbit has been evaluated over model tectonic features such as mountains and ranges, fracture zones, and trenches. Models are locally compensated and consist of both point mass dipoles and sheet mass dipoles. Masses and depths of compensation are chosen to approximate known gravity signatures. The results show that for two satellites at 160 km altitude with 3° separation, significant signal power (>1 μm/s) remains for most extended features at wavelengths less than 200 km. Furthermore, there is strong sensitivity in the signal from these features to lateral and vertical changes of the order of 1 km and less. In addition, the signal of hidden geologic structures such as dikes, salt domes, and ore bodies may also stand above 1 μm/s for this low orbiting pair. Thus, it may prove to be efficient to model the high-frequency GRAVSAT signal directly in terms of the parameters of tectonic-topographic features and their compensation.