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Geo-magnetic survey for estimating magnetic sources parameters by properties technique in Gol-e-Gohar area

Author Affiliations

  • 1Department of Mining and Metallurgy, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Ave, 15875-4413, Tehran, Iran
  • 2Department of Mining and Metallurgy, Amirkabir University of Technology (Tehran Polytechnic), 424 Hafez Ave, 15875-4413, Tehran, Iran

Int. Res. J. Earth Sci., Volume 7, Issue (2), Pages 13-26, May,25 (2019)

Abstract

In the current research paper, the evaluation of magnetic data of Gol-e-Gohar Iron Ore Anomaly No. 8, located about 50km southwest of Sirjan, Kerman Province, was discussed. According to geological studies, the main minerals of the area constitute magnetite and hematite created from secondary oxidation. Acquired geomagnetic data was processed after applying diurnal and IGRF corrections (some unimportant corrections such as the topographic correction are eliminated). The results show two major anomalies including anomaly with the positive pole in the northern part and other anomaly with the northwest-southeast trending in the SE part. After initial studies the north trend anomaly was found to be insignificant. Further studies were done on the southeast anomaly. Several methods are reviewed and compared for estimating depth and a two-dimensional modeling is introduced to achieve a more precise method for achieving acceptable depth and tilt angle revealing the edge of the anomaly. Techniques and methods used to estimate the depth of sub-surface structures, include Euler Deconvolution, (Source Parameter Imaging) SPI, Werner Deconvolution, and Potentq two-dimensional modeling. These methods initially were applied to validate on two-dyke models. The results of applying synthetic models on the above-mentioned methods indicated that all of the above methods have the high accuracy for applying over the actual data. After applying to the data of the study area, all three methods provided similar results, however, considering the results of synthetic models and the measured data, it is indicated that the three-dimensional Euler Deconvolution method is the most appropriate method for estimating the depth. Therefore, applying these methods on actual data, the depth to an anomaly is determined 35 m in the center and the northeast of the mass and up to 50 m in the southeast part of body. It should be noted that the precision of the proposed methods depends on the shape and the source of the anomaly. The more ideal and simple and not affected by several sources the mass form is, the more accurate the answer will be.

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