Performance assessment of structured and unstructured meshes in inversion of electrical resistivity and induced polarization surveys: Kabudan gold area, NE Iran

Articles in Press

Document Type : Research Paper

Authors

Faculty of Mining Engineering, Amirkabir University of Technology, Tehran, Iran.

10.22059/ijmge.2025.401349.595298

Abstract

This research investigates the inversion of electrical resistivity and induced polarization (IP) data acquired along geoelectrical profiles in the Kabudan gold prospect, Razavi Khorasan Province, northeastern Iran. To achieve higher modeling accuracy, two discretization schemes—structured quadrilateral meshes and unstructured triangular meshes—were implemented. The inversion results from both approaches were generally consistent and successfully depicted major subsurface geological features; however, the triangular mesh configuration achieved a lower RMS error and more effectively resolved fine-scale structural variations. Interpretation of the results delineated several geophysical anomalies, some of which showed strong agreement with drilling and assay data, most notably in borehole BH02. While resistivity models displayed the highest correlation with drill-core information, chargeability models provided complementary constraints for resolving sulfide-rich zones. Overall, the integration of geoelectrical survey results with drilling data proved to be a reliable approach for the detection of sulfide mineralization zones and for enhancing the resolution of subsurface structural interpretations.

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References

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International Journal of Mining and Geo-Engineering

Articles in Press, Accepted Manuscript
Available Online from 01 November 2025

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