Известия Томского политехнического университета: Инжиниринг георесурсов (Apr 2022)

ORE MINERALOGY OF SOKHATINY GOLD DEPOSIT (NORTHEAST ASIA, RUSSIA)

  • Timofey V. Timkin,
  • Valery G. Voroshilov,
  • Maria V. Yurkova,
  • Mansour Ziaii

DOI
https://doi.org/10.18799/24131830/2022/4/3585
Journal volume & issue
Vol. 333, no. 4
pp. 53 – 65

Abstract

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The relevance of the study is caused by the need to expand the mineral resource base of operating gold mining enterprises in Eastern Yakutia and the Magadan region. The main aim: to study the material composition of the ores of the Sokhatiny gold ore deposit and to establish the sequence of mineral formation. The methods: topomineralogical mapping of ores and metasomatites; study of transparent, transparent-polished and polished thin sections; scanning electron microscopy (TESCAN VEGA 3 SBU OXFORD X-Max 50); X-ray diffraction analysis (Rigaku Ultima IV), ICP-MS, geophysical (kappametry). Results. It was established that the gold ore mineralization at the Sokhatiny deposit has a hydrothermal-metasomatic and hypergenic genesis. In the first case, vein-veinlet bodies of a quartz-carbonate-sulfide composition were formed, confined to the zones of circum-ore beresitization rocks. In the second, there was a transformation of the products of the hydrothermal-metasomatic stage under the influence of exogenous factors. The metasomatic processes in the field are manifested in the form of areal propylization and beresitization of the host metamorphic shale rock. As a result of mineralogical and mineralografic research methods, the material composition of ores was studied in detail and the sequence of ore deposition was determined; a morphological description of native gold was carried out; new minerals were identified that were not previously described at the Sokhatiny deposit. The deposition of ore minerals went in three stages, which correspond to the following mineral associations: 1) quartz-calcite-barite-pyrite; 2) gold-polymetallic; 3) gold-bismuth-telluride. Based on the names, it follows that increased concentrations of gold are confined to later steps. In oxidized ores, native gold is also noted, which in its morphological parameters does not differ from primary one. The oxidation zone is characterized by low levels of addition of silver and other elements in gold, due to chemical dissolution in surface conditions.

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