F. Jamali; A.R. Arab Amiri; A. Kamkar Rouhani; A. Bahrami
Abstract
In any geophysical exploration, the final goal is to achieve an accurate image of the relevant underground property. In order to achieve this, the geophysical operation using the electrical resistivity and induced polarization (IP) methods is conducted to explore the sub-surface sulfide mineralization. ...
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In any geophysical exploration, the final goal is to achieve an accurate image of the relevant underground property. In order to achieve this, the geophysical operation using the electrical resistivity and induced polarization (IP) methods is conducted to explore the sub-surface sulfide mineralization. Considering the mineralization evidence in the Kaboudan area near the Bardeskan city, first, geophysical surveying of the polymetallic deposit is carried out using the electrical resistivity and IP methods by employing the rectangle array in order to detect the electrical anomalies in the area. Then for delineation of the identified anomalies and investigation of the mineralization in the area, the 2D resistivity and chargeability cross-sections are prepared and interpreted with the help of the geological information. This geophysical survey in the area has led to the identification of several potential areas for mineralization. Then in order to obtain a detailed picture of the sub-surface mineralization and an overview of the in-depth mineralization distribution, a 3D modeling of the acquired data is made, and the results of this modeling are shown in 3D forms. The mineralization zones are identified in the studied area from their high chargeability values as well as the low to medium electrical resistivity amounts. This can be attributed to the metal mineralization and the presence of sulfide minerals in the mineralization zones. Mineralization in many places of the studied area is determined with an approximate east-west trend as well as somewhat varying the intensities of the electrical resistivity and chargeability amounts. The geological and drilling information obtained from the area confirm the interpretations.
S. Najafi Ghoshebolagh; A. Kamkar Rouhani; A.R. Arab Amiri; H. Bizhani
Abstract
As many gold deposits are associated with sulfide zones, and the direct exploration of gold deposits using the geophysical methods is very difficult due to its low amount in the sub-surface, the direct exploration of sulfide zones by the geophysical electrical resistivity and induced polarization (IP) ...
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As many gold deposits are associated with sulfide zones, and the direct exploration of gold deposits using the geophysical methods is very difficult due to its low amount in the sub-surface, the direct exploration of sulfide zones by the geophysical electrical resistivity and induced polarization (IP) methods may lead to the indirect exploration of gold deposits. The gold deposit in the Kervian area is located in the Kurdistan shear zone, and is directly related to the sulfide, silica, and carbonate alteration units. After acquiring the resistivity and IP data, 2D modeling of the data is made in order to indirectly identify the gold-bearing zones in the surveyed area. As some of the identified geophysical anomalies indicating the sulfide zones may not be associated with the economic amounts of gold, in order to obtain an exploration pattern for the gold deposit in the studied area, a combination of the geophysical data modeling and interpretation results with the geological information and other exploratory data is used to reduce the uncertainty in identifying the gold-bearing zones in the studied area. Thus, modeling and interpretation of the geophysical data lead to identify the sub-surface anomalies as the locations of possible gold mineralization in the area, and then the drilling points are suggested in the area. Considering the geological studies and chemical analysis of the samples taken from the drilled boreholes crossing some of the geophysical anomalies, we conclude that the geophysical anomalies occurring inside the phyllite and carbonate units in the area can contain an economic amount of gold, and thus are recommended as the top priority for further exploration.