Equivalent-Source from 3D Inversion Modeling for Magnetic Data Transformation
- 1 Applied Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology, Bandung, Indonesia
Abstract
The well-known non-uniqueness in modeling of potential-field data results in an infinite number of models that fit the data almost equally. This non-uniqueness concept is exploited to devise a method to transform the magnetic data based on their equivalent - source . T he unconstrained 3D magnetic inversion modeling is used to obtain the anomalous source s, i.e. 3D magnetization distribution in the subsurface . Although the 3D model fitting the data is not geologically feasible, it can serve as an equivalent - source . The transformations , which are commonly applied to magnetic data (reduction to the pole, reduction to the equator , upward and downward continuation) , are the response of the equivalent - source with appropriate kernel functions. The application of the method to both synthetic and field data show ed that the transformation of magnetic data using the 3D equivalent - source gave satisfactory results. The method is relatively more stable than the filtering technique, with respect to the noise present in the data.
- C. A. Mendonca and J. B. C. Silva, “The Equivalent Data Concept Applied to the Interpolation of Potential Field Data,” Geophysics, Vol. 59, No. 5, 1994, pp. 722-732. doi:10.1190/1.1443630
- C. A. Mendonca and J. B. C. Silva, “Interpolation of Potential-Field Data by Equivalent Layer and Minimum Curvature: A Comparative Analysis,” Geophysics, Vol. 60, No. 2, 1995, pp. 399-407. doi:10.1190/1.1443776
- G. R. J. Cooper, “Gridding Gravity Data Using an Equivalent Layer,” Computer and Geosciences, Vol. 26, No. 2, 2000, pp. 227-233. doi:10.1016/S0098-3004(99)00089-8
- L. Cordell, “A Scattered Equivalent-Source Method for Interpolation and Gridding of Potential-Field Data in Three Dimensions,” Geophysics, Vol. 57, No. 4, 1992, pp. 629-636. doi:10.1190/1.1443275
- D. A. Emilia, “Equivalent Sources Used as an Analytic Base for Processing Total Magnetic Field Profiles,” Geophysics, Vol. 38, No. 2, 1973, pp. 339-348. doi:10.1190/1.1440344
- J. B. C. Silva, “Reduction to the Pole as an Inverse Problem and Its Application to Low-Latitude Anomalies,” Geophysics, Vol. 51, No. 2, 1986, pp. 369-382. doi:10.1190/1.1442096
- W. Menke, “Geophysical Data Analysis: Discrete Inverse Theory,” 3rd Edition, Academic Press, London, 2012.
- R. J. Blakely, “Potential Theory in Gravity and Magnetic Applications,” Cambridge University Press, Cambridge, 1995. doi:10.1017/CBO9780511549816
- W. H. Press, B. P. Flannery, S. A. Teukolsky and W. T. Vetterling, “Numerical Recipes: The Art of Scientific Computing,” 2nd Edition, Cambridge University Press, Cambridge, 1997.
- K. I. Kis, “Transfer Properties of the Reduction of Magnetic Anomalies to the Pole and to the Equator,” Geophysics, Vol. 55, No. 9, 1990, pp. 1141-1147. doi:10.1190/1.1442930
- S.-Z. Xu, C.-H. Yang, S. Dai and D. Zhang, “A New Method for Continuation of 3D Potential Fields to a Horizontal Plane,” Geophysics, Vol. 68, No. 6, 2003, pp. 1917-1921. doi:10.1190/1.1635045
- Y. Li and D. W. Oldenburg, “3-D Inversion of Magnetic Data,” Geophysics, Vol. 61, No. 2, 1996, pp. 394-408. doi:10.1190/1.1443968
- M. Fedi and A. Rapolla, “3-D Inversion of Gravity and Magnetic Data with Depth Resolution,” Geophysics, Vol. 64, No. 2, 1999, pp. 452-460. doi:10.1190/1.1444550
- A. H. Saad, “Understanding Gravity Gradients—A Tutorial,” Leading Edge, Vol. 25, No. 8, 2006, pp. 942-949. doi:10.1190/1.2335167