Dr. Theses

Geochemistry of stratiform pyrite deposits of the Greater Caucasus eastern segment

Novruzov Novruz A.

Distribution patterns are defined for rare, noble (Au, Ag) and other associate elements in texture-mineralogical types of ores, sulphide minerals, zones with oxidation and containing sandy-clayey beds of Eastern Caucasus pyrite deposits. Relationships have been determined among components in ores and degree of sulphide minerals’ enrichment by rare elements. Associate raremetal minerali­zation has the more development in pyrite-polymetallic deposits with high importance of lead and copper sulphosalts. Mineralogical-geochemical zonation in deposits is closely connected with space distribution of ore types and mineral associations. Primary geochemical zonation expressed by systematic change of concentrations of the main oreforming and admixture components and values of indicator relations manifests by zonation indicator value. General pattern in distribution of the main and admixture elements in ore deposit and circumore space can be used in prediction of pyrite mineralization on flanges and deep horizons. Distribution peculiarities in orecontaining series of some components (Tl, Ag, Hg, Sn and also Mo, Bi and others) enable to refer them to indicator ones for definition of buried ore accumulations.

Distribution parameters of admixture-elements in pyrite ores and sulphide minerals were used as geochemical criteria of physical-chemical conditions of oreformation process and also to define ore matter source. Comparative analysis of absolute content for Au, Ag and Ag/Au values in ores of pyrite-polymetallic deposits Filizchai, Katekh and Katsdag with corresponding values in meteorite standard shows relationship between gold-silver mineralization and assimilation crust source.

Correlation of geochemical spectra allows to reveal similarity and unsimilarity of pyrite deposits in region. Comparison with classic pyrite bearing provinces showed that level of rare elements concentrations and also of gold, silver of pyrite-polymetallic deposits of East Caucasus in a whole are inferior in the same ones of Ore Altay close to copper-zinc-pyrite of Ural and significantly exceed stratiform deposits of North PreBaikal and West TransBaikal.