Capabilities of geophysical methods in identification of potential gold-bearing structural karst zones in the Urals
https://doi.org/10.24930/2500-302X-2025-25-3-633-643
EDN: FPQVZP
Abstract
Research object. The results of geophysical works in the periphery of the Krasnoturyinsk ore cluster to assess the prospects of discovering gold-bearing placers in structural weathering crusts and karst formations. The structural-erosional-karst placers of the Mesozoic age in the Urals are characterized. Basic information about the geology and minerals of the Turinsko-Auerbakhovsky ore region is provided.
Research methods. A set of geophysical methods was used, including gravimetry, magnetometry, electroprofiling by radio interferometry, and audiomagnetotelluric sounding. The methodological foundations of field observations and the principles of office processing and interpretation of the obtained data are described.
Results. For the area under study, maps of absolute elevations of the day surface, gravitational and magnetic fields, as well as a map of apparent resistivity are presented. Transformed sections of the electrophysical parameters of the medium are constructed based on the results of processing the audiomagnetotelluric sounding data. The obtained sections are compared with the graphs of potential fields for the studied profiles. Characteristic features of geophysical fields and parameters for identifying the structural elements associated with predicted mineralization are discussed.
Conclusion. The main geophysical criterion for the detection of a contact-karst weathering crust, promising in terms of gold content, is assumed to be a synchronous decrease in the values of gravitational field and electrical resistance. A stepwise shift of the magnetic field level may serve as an additional sign. Areal geophysical surveys are not sufficient for identification of deep karst traps. Due to the complex shape of karst cavities, the correct location of exploration wells can only be determined based on the results of electromagnetic soundings.
About the Author
V. A. Davydov
Yu.P. Bulashevich Institute of Geophysics, UB RAS
Russian Federation
Russian Federation
100 Amundsen st., Ekaterinburg 620016
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Review
For citations:
Davydov V.A. Capabilities of geophysical methods in identification of potential gold-bearing structural karst zones in the Urals. LITHOSPHERE (Russia). 2025;25(3):633-643. (In Russ.) https://doi.org/10.24930/2500-302X-2025-25-3-633-643. EDN: FPQVZP
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