The Uzunpınar (Boztepe-Kırşehir) Zn-Pb±Cu mineralization: A metamorphosed SEDEX-type mineralization in the Kırşehir Massif

The Uzunpınar (Boztepe-Kırşehir) Zn-Pb±Cu mineralization is hosted within the gneiss and marbles of Paleozoic Kalkanlıdağ Formation of the Central Anatolian Crystalline Complex. The rocks observed in the mineralization area are mica gneiss, marble, migmatite, and microgranite, which were formed through high-grade metamorphism and anatexis of pelitic and carbonate protoliths. The mineralization has a stratiform geometry which extends approximately 1,850 m in a NE-SW direction. Six distinct mineralization levels (horizons), exhibiting similar characteristics and thicknesses ranging from 3.1–32.10 m, have been identified hosted within gneisses and marbles. These levels comprise ore bands and disseminations with thicknesses of 0.1–8 cm, aligned parallel to the foliation. Ore minerals are sphalerite, galena, chalcopyrite, and minor scheelite, while gangue minerals are pyrite, marcasite, pyrrhotite, gahnite, and Ba-feldspar. In the Uzunpınar mineralization, the alignment of ore bands with the host rock foliation, the presence of coarse-grained euhedral opaque minerals, foam textures, gahnite, Ba-feldspar, and the high Fe content in sphalerites serve as evidence for the influence of metamorphism on the mineralization. The stratiform geometry, syngenetic origin, and metal and mineral paragenesis suggest a SEDEX origin for the mineralization, later metamorphosed together with its host rocks.