Interpretation of magnetic data in the Chenar-e Olya area of Asadabad, Hamedan, Iran, using analytic signal, Euler deconvolution, horizontal gradient and tilt derivative methods

The main goal of the present work is delineating and estimating the depth of a magnetic anomaly in the Chenar-e Olya area of Asadabad, Hamedan, Iran. Ground magnetic data were acquired north of the region, every 15 m along lines that were spaced 10 m apart. Then, methods were used to estimate the depth and shape of the body causing the anomalies. Our pattern recognition criteria were based on analytic signal, Euler deconvolution, horizontal gradient, and tilt derivative obtained from magnetic data. Various steps were taken to decide, among the four methods, on the depth estimation and contact location of the magnetite body. The best contact location was found where the horizontal gradient contacts were isolated. Comparing parallel contacts of horizontal gradient with analytic signal methods, the analytic signal contacts were deemed more accurate, and discontinuity of the contact location was supplemented with tilt derivative and Euler deconvolution contacts. For depth estimation, in addition to the Euler deconvolution on the surface and tilt-depth estimation, upward continuation was applied, with a reduction to pole approach at heights of 10, 20, 30, and 40 metres, and then the Euler deconvolution method was performed on them. Ultimately, the results were compared with borehole data. There are six drilled boreholes in this area to validate the magnetic survey results for depth estimation and contact location. After calculating the contact location and depth of the magnetite body, the results show good agreement with the borehole data obtained within the calculated contact location.