Determination of maximum tilt angle from analytic signal amplitude of magnetic data by the curvature-based method

Pham Thanh Luan, Le Huy Minh, Erdinc Oksum, Do Duc Thanh
Author affiliations


  • Pham Thanh Luan VNU, Hanoi - University of Science, Faculty of Physics, Department of Geophysics, Ha Noi, Vietnam
  • Le Huy Minh Institute of Geophysics, Vietnam Academy of Science and Technology, Hanoi, Vietnam
  • Erdinc Oksum Süleyman Demirel University, Engineering Faculty, Department of Geophyisical Engineering, 32260 Isparta, Turkey
  • Do Duc Thanh VNU, Hanoi - University of Science, Faculty of Physics, Department of Geophysics, Ha Noi, Vietnam



the curvature-based method, tilt angle, analytic signalamplitude, edge detection, Tu Chinh-Vung May


Imaging buried geological boundaries is one of a major objective during the interpretation of magnetic field data in Geophysics. Therefore, edge detection and edge enhancement techniques assist a crucial role on this aim. Most of the existing edge detector methods require to obtain special points such as in general the maxima of the resulting image. One of the useful tools in estimating edges from magnetic data is the tilt angle of the analytical signal amplitude due to its value slightly dependence on the direction of magnetization. In this study, the maxima of the tilt angle of analytical signal amplitudes of the magnetic data was determined by a curvature-based method. The technique is based on fitting a quadratic surface over a 3×3 windows of the grid for locating any appropriate critical point that is near the centre of the window. The algorithm is built in Matlab environment. The feasibility of the algorithm is demonstrated in two cases of synthetic data as well as on real magnetic data from Tu Chinh-Vung May area. The source code is available from the authors on request.


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How to Cite

Luan, P. T., Minh, L. H., Oksum, E., & Thanh, D. D. (2018). Determination of maximum tilt angle from analytic signal amplitude of magnetic data by the curvature-based method. Vietnam Journal of Earth Sciences, 40(4), 354–366.




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