We apply equipotential surface curvatures to airborne gravity gradient data. The mean and differential curvature of the equipotential surface, the curvature of the gravity field line, the zero contour of the Gaussian curvature, and the shape index improve the understanding and geologic interpretation of gravity gradient data. Their use is illustrated in model data and applied to FALCON airborne gravity gradiometer data from the Canning Basin, Australia.

A method for automatic 3D model generation derived from airborne gravity gradient data was illustrated. The proposed method computed a volumetric distribution of curvatures that form a 3D image of possible density distributions. The method relies on spectral analysis and the equivalence of the power spectra of the classical mean and differential curvatures of equipotential surfaces to create pseudodepth slices of a quantity that describes the geometry of the surfaces: the shape index. The method was carried out in three steps. First, the pseudodepth slices of the vertical gravity gradient and the magnitude of the differential curvature components were generated. Second, equivalent pseudodepth slices of the shape index were generated. Finally, 3D interpolation was carried out to obtain the final model. The synthetic model data indicated that the vertical density contrasts were well modeled. A 3D model derived from FALCON airborne gravity gradiometer data from the Canning Basin, Australia, was compared to an independently interpreted integrated 3D earth geologic model.

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We display airborne gravity gradient data using curvature attributes of the equipotential surface to derive geometric shapes that can be associated with structural and geologic features. Concepts used in differential geometry that describe all geometric aspects of a surface are applied to airborne gravity gradiometry data. Gravity gradient components are ideal for this application because they are related to curvature of the gravitational potential. We also emphasize that with gravity methods, the surfaces for which the curvature attributes are derived represent the succession of equipotential surfaces, which, under favorable circumstances, correspond to one or more geologic surfaces that dominate the signature of the airborne gravity gradiometry data.

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