Gravity vs Pseudo-Gravity: A Comparison Based on Magnetic and Gravity Gradient Measurements
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Pseudo-gravity is a gravity-like accel-eration implied by constant magnetization of material on the basis of Poisson’s relationship. Pseudo-gravity anomalies from magnetic surveys, or pseudo-magnetic anomalies from observed (or computed) gravitational gradients can be used to enhance geologic interpretations of subsurface structures, such as their depth determination. We review the theory and fundamental assumptions behind Poisson’s relationship. Then, using magnetic and gravity gradient measurements in the Parkfield, California, area, we demonstrate the validity of this relationship, as well as the non-validity of the assumptions in cases where the gravitational gradient and magnetic data do not correlate.
KeywordsPseudo-gravity Magnetic anomaly Gravitational gradient Poisson’s relationship
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