GEOCHEMICAL ASSOCIATIONS IN THE SEDEFCHE ORE DEPOSIT, BULGARIA

ABSTRACT. The geochemical associations and spatial distribution of chemical elements in the Sedefche deposit are studied. The ore deposit is located in the easternmost part of the Zvezdel-Pcheloyad ore field. The data obtained during the exploration drilling program conducted in the period 2019-2020 by Gorubso-Kardzhali JSC was used to determine the spatial correlation between the chemical elements and their geochemical associations. A total of 28 elements were included for the statistical data processing. The results of the factor analysis reveal that the total variation is decomposed on 7 factor axes. The results of the 3D modelling of the factor scores contributes to clarify the geochemical associations and spatial distribution of groups of elements characterised by a certain similarity. The association of ([Ag, Pb, Sb, Au] Cu, As, Cd) from factor 2 represents the distribution of the main ore elements in the deposit. The other associations that follow the morphology of the ore bodies are represented by factor 1 ([Mn, Be, Co, Zn, Fe] Al, Ni, Tl) and factor 3 ([Hg, Tl, Mo, As] S, Au, K, Sb) and probably describe the distribution of the Quartz-sphalerite-galena, the Quartz-arsenopyrite, and the Sulfosalt parageneses.