Electrical imaging of gold-bearing mineralization zones through 3D geophysical modeling

Articles in Press

Document Type : Research Paper

Authors

1 School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran.

2 Civil Engineering Department, Islamic Azad University of Shabestar, Tabriz, Iran.

10.22059/ijmge.2025.395329.595250

Abstract

This study illustrates the use of 3D geoelectrical inversion modeling to accurately identify and characterize gold mineralization at a high potential zone in Iran. Nine parallel time domain geo-electrical profiles were acquired using a pole-dipole array, covering a total of 200 meters per profile with 10-meter electrode spacing. The induced polarization and resistivity data were processed and inverted using an unstructured tetrahedral mesh, enhancing the resolution and providing a more precise understanding of subsurface anomalies. The results revealed distinct chargeability and resistivity profiles, which were correlated with siliceous dikes and sulfide-rich zones, both of which are indicative of potential gold mineralization. Shallow anomalies (20-50 meters) align with hornfels layers and display characteristics typical of low-sulfidation epithermal systems, suggesting favorable conditions for gold mineralization. Furthermore, deeper anomalies (50-70 meters), associated with intrusive bodies, exhibit high resistivity and chargeability, consistent with gold-enriched siliceous veins. The study emphasizes the importance of integrating geophysical inversion techniques in gold exploration, as they provide a cost-effective and accurate method for identifying mineralized zones, reducing exploration uncertainties, and enhancing resource estimation. This approach contributes significantly to the efficiency and success of mining ventures by providing valuable insights into subsurface structures.

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References

[1]       Gadallah, M.R. and R. Fisher, Seismic Fundamentals, in Exploration Geophysics, M.R. Gadallah and R. Fisher, Editors. 2009, Springer Berlin Heidelberg: Berlin, Heidelberg. p. 17-29.
[2]       Dashtbankhor, B., M.K. Hafizi, and F. Jafari, Gold exploration in silica veins in Bajestan County using IP/Rs method, in The Second National Congress of New Technologies of Iran with the Aim of Achieving Sustainable Development. 2015.
[3]       Talebi, M.A., et al., Geophysical modeling of resistivity and electrical chargeability data for exploration of building stones, case study: Atashkooh travertine. Applied geophysical research, 2022. 8(1): p. 27-40.
[4]       Oldenburg, D. and Y. Li, 5. Inversion for Applied Geophysics: A Tutorial. Near-surface Geophysics, 2005.
[5]       Pourhashemi, S., R. Ghanati, and A. AliHeidari, Time-domain induced polarization tomography inversion. International Journal of Mining and Geo-Engineering, 2024. 58(2): p. 153-160.
[6]       Mostafaei, K. and H. Ramazi, Application of electrical resistivity method in sodium sulfate deposits exploration, case study: Garmab, Iran. Journal of Biodiversity and Environmental Sciences, 2015. 6: p. 2220-6663.
[7]       Talebi, M.A., et al., 3D inverse modeling of electrical resistivity and chargeability data through unstructured meshing, a case study for travertine exploration. International Journal of Mining and Geo-Engineering, 2023. 57(2): p. 131-140.
[8]       Rücker, C., T. Günther, and F. Wagner, pyGIMLi: An open-source library for modelling and inversion in geophysics. Computers & Geosciences, 2017. 109: p. 106-123.
[9]       Blanchy, G., et al., ResIPy, an intuitive open source software for complex geoelectrical inversion/modeling. Computers & Geosciences, 2020. 137: p. 104423.
[10]     Damavandi, K., et al., Comparison of geoelectric modeling based on structural and non-structural mesh, case study: Tehran-North Expressway, in The Second National Conference on Data Mining in Earth Sciences. 2021.
[11]     Ahmadi, R. and J. Ehsan nejad, 3-D geophysical modeling using 2-D acquisitioned data and geostatistics for Yazd, Ali-Abad copper deposit to propose optimal drilling location. Researches in Earth Sciences, 2024. 15(2): p. 77-95.
[12]     Loke, M., Tutorial: 2-D and 3-D Electrical Imaging Surveys. 2001.
[13]     Chambers, J., et al., Bedrock detection beneath river terrace deposits using three-dimensional electrical resistivity tomography. Geomorphology, 2012. s 177–178: p. 17–25.
[14]     Doetsch, J., et al., Imaging and Quantifying Salt-Tracer Transport in a Riparian Groundwater System by Means of 3D ERT Monitoring. Geophysics, 2012. 77: p. B207-B218.
[15]     Uhlemann, S., et al., Four-dimensional imaging of moisture dynamics during landslide reactivation. Journal of Geophysical Research: Earth Surface, 2017. 122(1): p. 398-418.
[16]     Damavandi, K., et al., Geoelectrical modelling of a landslide surface through an unstructured mesh. Bollettino di Geofisica Teorica ed Applicata, 2022.
[17]     Geuzaine, C. and J.-F. Remacle, Gmsh: A 3-D Finite Element Mesh Generator with Built-in Pre- and Post-Processing Facilities. International Journal for Numerical Methods in Engineering, 2009. 79: p. 1309-1331.
[18]     Abedi, M., A focused and constrained 2D inversion of potential field geophysical data through Delaunay triangulation, a case study for iron-bearing targeting at the Shavaz deposit in Iran. Physics of The Earth and Planetary Interiors, 2020.
[19]     Danaei, K., et al., 3D inversion of gravity data with unstructured mesh and least-squares QR-factorization (LSQR). Journal of Applied Geophysics, 2022. 206.
[20]     Gouet , D., et al., Gold Mineralization Channels Identification in the Tindikala-Boutou Area (Eastern-Cameroon) Using Geoelectrical (DC & IP) Methods: A Case Study. International Journal of Geosciences, 2013. 4: p. 643-655.
[21]     Guo, W., et al., Geophysical exploration for gold in Gansu Province, China. Exploration Geophysics - EXPLOR GEOPHYS, 1999. 30.
[22]     Gurin, G.V., et al., Application of the Debye decomposition approach to analysis of induced-polarization profiling data (Julietta gold-silver deposit, Magadan Region). Russian Geology and Geophysics, 2015. 56(12): p. 1757-1771.
[23]     Malekzadeh Shafarudi, A., M.R. Heydarian Shahri, and M.H. Karimpour, Mineralization and geophysical exploration using IP/RS and ground magnetometry in and around the MA-I area, Maherabad Porphyry Copper-Gold Exploration Area, Eastern Iran. Economic geology, 2010. 1(1): p. 1-17.
[24]     Aalaminia , Z., et al., Mineralization and interpretation of geophysical survey, IP/RS, in Hassan Abad Gold-Antimony, northeast of Iran. Iranian Journal of Crystallography and Mineralogy, 2011. 18(4): p. 723-734.
[25]     Paterson, N.R. and P.G. Hallof, Geophysical exploration for gold, in Gold metallogeny and exploration, R.P. Foster, Editor. 1991, Springer US: Boston, MA. p. 360-398.
[26]     Sono, P., et al., An integrated use of induced polarization and electrical resistivity imaging methods to delineate zones of potential gold mineralization in the Phitshane Molopo area, Southeast Botswana. Journal of African Earth Sciences, 2020. 174.
[27]     Ruchkin, G. and Y.N. Deryugin, Zolotonosnost’rannedokembriiskikh zhelezitykh kvartsitov. Obzor VIEMS Geologiya, metody poiskov i razvedki mestorozhdenii metallicheski poleznykh iskopaemykh, 1988.
[28]     Goryachev, N., Gold Deposits in the Earth’s History. Geology of Ore Deposits, 2019. 61: p. 495-511.
[29]     Aliyari, F., E. Rastad, and M. Mohajjel, Gold Deposits in the Sanandaj–Sirjan Zone: Orogenic Gold Deposits or Intrusion-Related Gold Systems? Resource Geology, 2012. 62.
[30]     Heidari, S.M., et al., A review of tectono-magmatic evolution and gold metallogeny in the inner parts of Zagros orogeny: a tectonic model for the major gold deposits, western Iran. Eurasian Mining, 2016: p. 3-20.
[31]     Final exploration report of the study area. 2023.
[32]     M. Mehrparto, N.K.N., Geological report of the 1:100,000 map of Varzaghan and Kalibar, Geological and Mineral Exploration Organization of the country. 1999.
[33]     Farahani, N., et al., Exploration of gold-bearing barite veins using IP and RS methods, in 18th Iranian National Geophysical Congress. 2018.
[34]     Park, J.-O., Y.-J. You, and H.J. Kim, Electrical resistivity surveys for gold-bearing veins in the Yongjang mine, Korea. Journal of Geophysics and Engineering, 2009. 6(1): p. 73-81.
[35]     Moradzadeh, A. and A. Arab Amiri, Parametric inverse modeling of polarization and resistivity data of a durable mineral index, in The 8th Conference of the Geological Society of Iran. 2009.
[36]     Shahmirzae, M. and M. Darijani, Two-dimensional geomagnetic forward modeling using adaptive finite element method and investigation of the topographic effect. Journal of Applied Geophysics, 2014. 105.
[37]     Groves, D., et al., Gold Deposits in Metamorphic Belts: Overview of Current Understanding,Outstanding Problems, Future Research, and Exploration Significance. Economic Geology, 2003. 98: p. 1-29.
[38]     Seimetz, E.X., et al., Geoelectric Signature of Gold Mineralization in the Alta Floresta Gold Province, Mato Grosso State, Brazil. Minerals, 2023. 13(2): p. 203.
International Journal of Mining and Geo-Engineering

Articles in Press, Accepted Manuscript
Available Online from 07 July 2025

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