Invers modeling and interpretation of magnetic and geoelectrical data in the gold area of Hassan abad (south of Golpayegan)

Authors

1 PhD student, Department of Geology, Faculty of Science, Lorestan University, Khorramabad, Iran

2 Professor, Department of Geology, Faculty of Science, Tehran University, Tehran, Iran

Abstract

Hassan Abad gold field is located in the central part of Sanandaj-Sirjan, 18 kilometers south-west of Golpayegan. Geophysical exploration was done by carrying out special resistivity and induced polarization magnetometry, and in order to estimate the depth of possible magnetic sources, Euler processing and mixing was applied, then three-dimensional inverse modeling of the magnetic data of the area was done based on Lee Waldenberg's algorithm. The maximum depth of the magnetic self-receptivity estimated from the inversion results was consistent with the average depth of the magnetic sources obtained by Euler's interpolation method. In addition, the two-dimensional models resulting from the inversion of specific resistance and induced polarization data were compared with the vertical sections of the three-dimensional model of magnetic self-absorbance. Under the influence of metamorphism, rock sequences have lost their initial order and intensity is not the same, and they are observed as shear zones from ductile to brittle to brittle. Gold mineralization with appropriate grade along with bismuth, tungsten, silica veins and veins containing sulphide mineralization in the form of pyrite, arsenopyrite, galena, sphalerite, chalcopyrite, and pyrrhotite has occurred. Alteration zones include argillic, phyllic, cercitic, silicic sulfide. In the stages of specific resistance modeling, faults are well recognized, and mineralization and drilling are located in these vein areas and in the fault zone. Eighteen cored boreholes and twenty RC boreholes were drilled. Geological surveys of alteration and surface and subsurface mineralization of boreholes show gold mineralization in areas with high magnetic susceptibility changes.

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Main Subjects


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