Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit
This research employs a combined geophysical approach, utilizing electrical resistivity tomography (ERT) and induced polarization (IP) imaging, to characterize the subsurface architecture and identify copper-bearing zones at the Takhte-Gonbad porphyry copper deposit within the Kerman metallogenic belt, Iran. The acquired field data were inverted using two distinct methodologies: conventional Tikhonov regularization and sparsity-based regularization. The resulting inverse models successfully delineated two principal E-W trending mineralized zones, which are distinguished by coherent low-resistivity and high-chargeability anomalies diagnostic of disseminated sulfide mineralization. These geophysical signatures exhibit a strong spatial correlation with surface-mapped zones of phyllic and argillic alteration and are further validated by borehole assay data confirming local copper grades exceeding 1%. A comparative assessment of the inversion results indicates that sparsity-based regularization produces subsurface models with sharper lithological boundaries and improved delineation of compact, high-contrast ore bodies, making it particularly effective for resolving localized features at the deposit scale. In contrast, Tikhonov regularization yields smoother models that are better suited for representing broader, regional-scale geological structures. Overall, both inversion approaches are capable of resolving the main subsurface features; however, they emphasize different aspects of the subsurface due to their inherent regularization properties. Accordingly, the choice between them should be guided by the geological objectives rather than interpreted as a general superiority of one method over the other.
Hosseini, M. , Abedi, M. , Mirmohammadi, M. , Ghezelbash, R. and Sadraeifar, B. (2026). Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit. Geopersia, (), -. doi: 10.22059/geope.2026.406213.648850
MLA
Hosseini, M. , , Abedi, M. , , Mirmohammadi, M. , , Ghezelbash, R. , and Sadraeifar, B. . "Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit", Geopersia, , , 2026, -. doi: 10.22059/geope.2026.406213.648850
HARVARD
Hosseini, M., Abedi, M., Mirmohammadi, M., Ghezelbash, R., Sadraeifar, B. (2026). 'Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit', Geopersia, (), pp. -. doi: 10.22059/geope.2026.406213.648850
CHICAGO
M. Hosseini , M. Abedi , M. Mirmohammadi , R. Ghezelbash and B. Sadraeifar, "Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit," Geopersia, (2026): -, doi: 10.22059/geope.2026.406213.648850
VANCOUVER
Hosseini, M., Abedi, M., Mirmohammadi, M., Ghezelbash, R., Sadraeifar, B. Sparsity-based Regularization of Geophysical Time-domain Electrical Resistivity and Induced Polarization Data: A Strategy for Imaging Takhte-Gonbad Porphyry Cu Deposit. Geopersia, 2026; (): -. doi: 10.22059/geope.2026.406213.648850
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