Geophysical prospecting of a copper deposit using airborne magnetometry, induced polarization and resistivity methods in the Torud, Semnan Province, Iran.

Authors

Abstract

Geophysical methods are suitable methods for prospecting and exploration of mineral deposits. Using two or more exploratory methods together and combining them with other information such as geological studies can increase the probability of discovering and reaching promising areas. According to the evidence of metallic and sulfide mineralization in the study area (the exploratory area of Pirmardan), the use of magnetic, induced polarization (IP) and electrical resistivity (Res) for prospecting and exploration of  the mineralization in the area is of great importance. The position and the spatial relationship between mineralization and lineaments have long been considered by geologists. Airborne magnetic data and geological information are used to diagnose and distinguish the general trends of structures, lineaments, and large faults using tilt filter on magnetic data. By processing and interpretation of the airborne magnetic data of the region, the existing structures in the region have been investigated. Moreover, considering the available geological information in the region, the induced polarization and the electrical resistivity data have been acquired using the rectangle arrangement to detect the subsurface anomalies and also using the dipole-dipole arrangement along two survey lines to obtain the lateral and depth extension of the anomalies. Airborne magnetic data processing has been performed using Oasis Montaj software, and also, processing and modeling of induced polarization and electrical resistivity data have been carried out using RES2DINV and ZONDRES2D software packages. The final results obtained from the interpretation of airborne magnetic, induced polarization and electrical resistivity data confirm the relationship between lineaments and the probability of hidden copper reserves in the study area. These results have led to propose five spots for exploration drilling.

Keywords


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