The first 111 days of preliminary data from GRACE were used to produce a map of the Earth’s gravity anomalies. A gravity anomaly map shows us how much the actual Earth’s gravity field departs from “normal” as defined by a simplified mathematical gravity model that assumes the Earth is perfectly smooth and featureless. In this grayscale representation, brighter areas represent positive gravity a...

We present the development of an algorithm for inverting multi-component gravity gradiometer data to recover three-dimensional (3-D) distributions of density contrast for salt imaging. The algorithm is a direct adaptation of the author’s earlier work on 3-D inversion of magnetic data. The underlying method is based upon a regularized inversion that constructs a density contrast distribution hav...

$EVWUDFW With airborne gravimetry routinely reaching accuracies of 1-2 mGal at 5-10 km resolution, it is a challenge to perform a reliable downward continuation of the gravity anomalies at altitude. Airborne gravimetry is especially suited for geoid determination in mountainous and polar regions, due to the random, alias-free sampling of the terrain, relative to typical surface surveys. In the ...

Various techniques have been developed to interpret potential field data which are broadly categorized as: Forward and Inverse modeling (Blakely, 1995). Ambiguity in identification and characterization of the sources from the potential field data makes formulation of initial model a critical step while analyzing the data. The second category of techniques (inversion) shows many constraints such...

We present a feasibility study for interpretation of gravity gradient surveys in a single borehole using both an analytic and inverse-based approach. We analytically solve for distance and direction angles to a point source using the components of the gravity gradient tensor from a set of observations in a single borehole. We then generalize this approach to include the response due to a prisma...

The Green's function of the Poisson equation, and its spatial derivatives, lead to a family of wavelets specifically tailored to potential fields. Upward continuation of the field is seen to be identical to these wavelets' scale change operation. The maxima at all heights of the field's horizontal gradients are termed the field's multiscale edges. A multiscale edge's field strength variation an...