Document Type : Research Paper

Author

University of Baghdad - College of Science

10.37652/juaps.2011.44071

Abstract

:Differential Operators (Gradient, Laplacian and Biharmonic) have been used to
determine anomaly characteristics using theoretical gravity field for prismatic bodies with different
top depths, dimensions and density contrasts. The concepts of gradient and laplacian operator are
widely used in image processing. The intersection between the gravity field and the three differential
operator's fields could be used to estimate the depth to the top of the prismatic bodies regardless of
their differences in dimensions, depths and density contrasts. The Biharmonic Operator has an
excellent result, were two zero closed contour line produced. The outline of the internal closed zero
contour line define precisely the dimension of the prismatic bodies. The distance between this zero
contour and the maxima of the Laplacian Operator define the exact depth to the top of the prismatic
bodies. The maxima of the Biharmonic amplitude could be used for density contrast approximation.
This is the first attempt to use such technique for estimating body characteristics. Also, the
Biharmonic Operator has high sensitivity to resolve hidden small anomaly due the effect of large
neighborhood anomaly, the 2nd derivative Laplacian Filter could reveal these small anomaly but the
Biharmonic Operator could indicate the exact depth. The user for such technique should be very care
to the accuracy of digitizing the data due to the high sensitivity of Biharmonic Operator. The validity
of the method is tested using field example for salt dome in Gulf Coast basin

Keywords

Main Subjects

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