Geologic, mineralogic and geochemical properties of Elmaalan (Arsin-Trabzon) massive sulphide mineralization

Elmaalan massive sulphide mineralization located in the northern zone of the Eastern Pontides, lies primarily within the immediate footwall of Upper Cretaceous dacite and pyroclastics, which comes it is overlain by Upper Cretaceous dacite and pyroclastics at hanging wall. In terms of structural and textural features, there are five peculiar ore types exist as such massive, breccia filling, clastics, stockwork and disseminated. Determined ore minerals include pyrite, chalcopyrite, sphalerite, galena, fahlers, bornite and in less amount chalcosine and covellite together with digenite, on the other hand quartz, barite, carbonates and clay minerals, sericite and gypsum are exist as gangue. Mineralization is observed associated with silisification, sericitization, clay alteration and chloritization. According to mass transfer calculations, the rate of Si, Fe and K elements increases, whereas that of Ca, Na and Al decreases, toward the ore-zone. The ? 34S values, obtained from pyrite, chalcopyrite and galena, range from - 2,42? to 4,66? show that the source of sulphur is magmatic in origin. The ? 18O values of solutions equilibrated with quartz vary between -0,7? and +12,8 and with clays are in between -0,3? and +26,5?. Homogenization temperatures vary between 130 0C and 414 0C, and salinity values are in between %0,35-11,22 NaCl. The formation temperature of 315 0C is defined from oxygen isotope geothermometer. The geological, mineralogical and geochemical works suggest that Elmaalan mineralization is a Kuroko type massive sulphide ore.Key Words: Elmaalan, Kuroko, Massive sulphide, Hydrothermal alteration, Fluid inclusion, S Isotope, O-H Isotopes?