Geoelectric structure of the Tar Fault Zone in the Middle Urals according to audiomagnetotelluric soundings

Authors

  • V. A. Davydov Yu. P. Bulashevich Institute of Geophysics, Ural Branch of the Russian Academy of Sciences, Russian Federation

DOI:

https://doi.org/10.24028/gzh.0203-3100.v42i3.2020.204708

Keywords:

audiomagnetotelluric sounding, ore deposits, fault, geoelectric section, ore mineralization

Abstract

Currently, the reduction of reserves and forecast resources of ore minerals due to the development of previously discovered deposits continues. The reproduction of reserves is possible due to additional exploration of the flanks and deep horizons of known ore objects. To study the geoelectric structure of the Ural ore-bearing structures, audiomagnetotelluric soundings were carried out along sub-latitudinal profiles crossing the zone of the Degtyarsky fault near the largest pyrite deposit in the Middle Urals. Field observations were performed using the OMAR-2 universal broadband equipment developed at the Institute of Geophysics, Ural Branch of the Russian Academy of Sciences for electrometric studies of urbanized territories. The applied hardware-software measuring complex is designed to effectively suppress industrial noise with additional methods for digital filtering of network harmonics. The cameral processing of audiomagnetotelluric data consisted in transforming the obtained frequency sounding curves into deep sections of geoelectric parameters using an original transformation algorithm. Based on the materials of the work, lithological and tectonic boundaries of a complex rock complex adjacent to the Degtyarsky regional fault are identified. Electric prospecting methods confidently trace the surface of the bedrock base, and weakened zones are also traced. Studies have shown a good correlation of geoelectric sections with real geological conditions. Good identification of the fault-bearing and ore-controlling structures is noted, which makes it possible to identify areas of mineralization that are promising for mineralization that do not reach the surface. According to the results of the research, places of possible concentration of copper and nickel-cobalt mineralization are identified.

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Published

2020-06-10

How to Cite

Davydov, V. A. (2020). Geoelectric structure of the Tar Fault Zone in the Middle Urals according to audiomagnetotelluric soundings. Geofizicheskiy Zhurnal, 42(3), 162–174. https://doi.org/10.24028/gzh.0203-3100.v42i3.2020.204708

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Section

Articles