NEWNOVEL METHOD TO ESTIMATE BODY CHARACTERISTICS (DIMENSIONS, DEPTHS AND DENSITY CONTRASTS) OF THREE DIMENSIONAL PRISMATIC BODIES BY APPLYING DIFFERENTIAL OPERATORS (GRADIENT g , LAPLACIAN 2Z AND BIHARMONIC 4Z ) TO THEIR GRAVITY FIELDS | ||
| Journal of University of Anbar for Pure Science | ||
| Article 20, Volume 5, Issue 1, April 2011, Pages 65-82 PDF (3.04 M) | ||
| Document Type: Research Paper | ||
| DOI: 10.37652/juaps.2011.44071 | ||
| Author | ||
| Ali M. Al-Rahim* | ||
| University of Baghdad - College of Science | ||
| 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 | ||
| Gravity; Depth Estimation; Prismatic bodies; Differential Operator; Gradient; Laplacian; Biharmonic | ||
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