Calculation of gravity and magnetic anomalies of finite-length right polygonal prisms.

J. W. Cady

doi:10.1190/1.1441045

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Calculation of gravity and magnetic anomalies of finite-length right polygonal prisms.

J. W. Cady

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Abstract

An equation is derived for the vertical gravity field due to a homogeneous body with polygonal cross‐section and finite strike‐length. The equation can be separated into the two‐dimensional (2-D) terms of Talwani et al. (1959) and exact terms for the contributions of the ends of the prism. Equations for the magnetic field due to a similar body were derived by Shuey and Pasquale (1973), who coined the term “two‐and‐a‐half dimensional” (2 1/2-D) to describe the geometry. Magnetic intensities are expressed as a vector sum, from which the common dot product formulation can be obtained by binomial expansion.

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J. W. Cady. 1980. Calculation of gravity and magnetic anomalies of finite-length right polygonal prisms.. https://doi.org/10.1190/1.1441045

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