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Pancarli Ni-Cu±(PGE) sulfide deposit occurs in the Neoproterozoic basement complex of the Bitlis massif, which is one of the Andean-type active continental margin fragments with arc-type assemblages represented by the Cadomian orogenic belt. Pancarli sulfides are associated with quartzo-feldspathic gneisses (country rock) and mafic intrusions (host rock). Composed of only semi-massive ore, the Ni-Cu±(PGE) sulfide deposit is a small-scale deposit, and it does not contain net-textured and disseminated ore. The mineral assemblage comprises pyrrhotite, pentlandite, and chalcopyrite. The semi-massive ore samples contain 2.2 wt.%−2.9 wt.% Ni, 0.8 wt.%−2.2 wt.% Cu (Cu/(Cu+Ni)=0.2−0.5) and 0.13 wt.%−0.17 wt.% Co. The Cu/Ni ratios (average 0.57) are consistent with the segregation of sulfides from a basaltic magma. Low Pt+Pd100%S values of 0.08 ppm−0.89 ppm, relatively low Pt/Pd ratios of 0.2–1.4, and Pd/Ir ratios of 4.5–39 have also been revealed. These values demonstrate that the magma reached S saturation before its emplacement and the mineralization with high Cu/Pd ratios formed by sulfides segregated from a PGE-depleted magma. δ34S isotope values (average −3.1‰) of Pancarli sulfides are lower than mantle source. Negative δ34S value indicates contamination from surrounding rocks. Concerning the composition, remobilization style and magma type, the Pancarli Ni-Cu±(PGE) sulfide deposit is similar to the deposits associated with Andean-type magmatic arcs located in the convergent plate margin settings. [ABSTRACT FROM AUTHOR]

Graphical abstract Hıghlıghts • HMS is the first sediment-related VMS deposit discovered in the Anatolia. • Containing more than 1% Cu-25 million tons reserve, ÇMC. • HMS mineralization may have formed in a back-arc rift tectonomagmatic environment. Abstract Hanönü massive sulfide (HMS) mineralization is the first sediment-hosted massive sulfide deposit discovered in Anatolia (Turkey). Containing more than 1% Cu and with more than 25 million tonnes reserve, the HMS mineralization is located in the Çangaldağ Metamorphic Complex (CMC) in the central Pontides within meta-volcaniclastic rocks with mafic sill and/or lava interlayers. Rocks related to mineralization were exposed to metamorphism under the greenschist facies conditions. Tectonism and metamorphic processes affected all units including ore. The HMS mineralization consists dominantly of Cu (0.2–6.9%) accompanied by Zn (239 ppm–1%) and comprises massive, banded and disseminated sulfide bodies. The main ore minerals include pyrite, chalcopyrite, with minor sphalerite and magnetite. The regular stratigraphy displaying uninterrupted layers of volcanoclastics contains mafic lava or sills within the sequence with the mineralization initially emplaced within immature clastics and then subjected to metamorphism as a package, which indicates that the ore and wall rocks formed in the same paleotectonic environment. Data obtained from melt models of mafic lava or sills related to the HMS mineralization indicate these rocks formed in back-arc basins from a mixture of 70% depleted MORB mantle and 30% asthenospheric melt with melting degrees possibly of 8–15%. According to isotope data, lead from the HMS mineralization may be sourced from an arc-related environment, with magmatic activity in the lower crust and upper mantle. Geologic and geochemical data indicate that the HMS mineralization may have formed in a back-arc rift tectonomagmatic environment. [ABSTRACT FROM AUTHOR]

The Ortaklar VMS deposit is hosted in the Koçali Complex consisting of basalts and deep sea pelagic sediments, which formed by rifting and continental break-up of the southern Neotethyan in Late Triassic. The basalts are of NMORB-type without notable crustal contamination. From the surface to depth, the Ortaklar deposit consists of a gossan zone, a thick massive ore zone and a poorly developed stockwork zone. Primary mineralisation is characterised by distinctive facies including sulphide breccias (proximal), graded beds (distal), stockworks and chimney fragments. Ore mineral abundances decrease in the order of pyrite, magnetite, chalcopyrite, and sphalerite. Two distinct phases of mineralisation, massive magnetite and massive sulphide, are present in the Ortaklar deposit. Textural evidence (e.g., magnetite replacing sulphides) and the spatial relationships with the host rocks indicate that magnetite and sulphide minerals were generated in different stages. The transition from sulphide to magnetite mineralisation is interpreted to relate to variation in H 2 S content of ore fluids. The 1st stage massive sulphide ore might have formed by early hydrothermal fluids rich in Fe and H 2 S. The 2nd stage massive magnetite might have formed by later neutral hydrothermal fluids rich in Fe but poor in H 2 S, replacing the pre-existing sulphide ore. The alteration patterns, mineral paragenesis, lithological features (massive ore-stockwork ore-gossan) of the Ortaklar deposit together with its trace elements, Cu-Pb-Zn-Au-Ag and REE signatures are all consistent with a Cyprus-type VMS system. The δ 34 S values in pyrite and chalcopyrite samples range from 2.6 to 5.7‰, indicating that the hydrothermal fluids were associated with sub-seafloor igneous activity, typical of Cyprus-type VMS deposits. However, magnetite formed later than sulphide minerals in the Ortaklar deposit, contrasting with typical Cyprus-type VMS deposits where magnetite generally occurs in lower sections. Consequently, although the Ortaklar deposit generally conforms to Cyprus-type deposits, it is distinguished from them by its late stage and high magnetite concentration. Thus, the Ortaklar deposit is thought to be an exceptional and perhaps unique Cyprus-type VMS deposit. [ABSTRACT FROM AUTHOR]

• Zeybek massive sulfide deposit is one of the recent discoveries, which is located in Turkey. • The Zeybek VMS mineralization is similar with mafic-siliciclastic type VMS deposits. • Cu-rich massive ore samples yielded, 178 ± 2.2 Ma (MSWD: 4.1) by Re-Os geochronological age. • The Zeybek VMS occurred in an arc-back arc tectonic environment. Located in the north of Anatolia, the Pontide Orogenic Belt hosts Turkey's most important volcanogenic massive sulfide (VMS) deposits. Studies completed in the last ten years have discovered new massive sulfide deposits in the Central Pontide zone. The Zeybek VMS deposit is one of these newly-discovered deposits found in the Central Pontides. This deposit is associated with the Çangaldağ Metamorphic Complex occurring as east-west-striking tectonic slices. The Çangaldağ Metamorphic Complex is an allochthonous mass of metavolcanic, metavolcaniclastic and metaclastic rocks in the form of imbricated tectonic slices. Zeybek massive sulfide deposit is located within metaclastic rocks intercalated with mafic sills or lava flows in this complex. The major ore mineral paragenesis in the Zeybek VMS deposit comprises pyrite, chalcopyrite and sphalerite, with lower amounts of bornite, covelline, chalcocite and magnetite. With thirty thousand meters of drilling in the mineralized area, 20 million ton resources with 0.32 wt% Cu were determined. According to the wall-rock mineralization relationships, mineralization style and ore geochemistry of the Zeybek VMS mineralization, it is similar to a mafic-siliciclastic type volcanogenic massive sulfide formation. Re-Os geochronologic studies of chalcopyrites from the Cu-rich massive ore samples obtained a 178 ± 2.2 Ma (MSWD: 4.1) 187Re/188Os against 187Os/188Os isochron. Geochemical and isotopical age data associated with the Zeybek VMS deposit indicate that the mineralization occurred in an arc-back arc tectonic environment, which developed in Middle Jurassic age intra-ocean as a result of the closure of north-ward subduction that resulted the closure of the Tethys ocean. [ABSTRACT FROM AUTHOR]

[Display omitted] • Say Yayla VMS deposit is associated with Middle Jurassic arc volcanism. • Say Yayla VMS occurred in an arc tectonic environment. • Mafic and felsic metavolcanics are the host-rocks of the Say Yayla VMS. The central part of the Pontide Orogenic Belt, located in northern Anatolia, is a segment of the Alpine-Himalayan orogeny. Çangaldağ Metamorphic Complex (CMC) occurs within this segment which consists of ensimatic island arc volcanics and deep sea sediments which occasionally cut cross by mafic sills/dykes. They were exposed to metamorphism under the greenschist facies conditions and remain in tectonic contact with each other. The Say yayla mineralization is one of the recently discovered volcanogenic massive sulfide (VMS) deposits in the CMC with a remarkable Au content. The mafic and felsic metavolcanic rocks are the host-rocks of the Say Yayla mineralization and the ages determined by U-Pb zircon grains of these felsic volcanic rocks range from 170 Ma to 165 Ma indicating Middle Jurassic time. At the 0.1% cut-off grade, 7.5 million tons of resource has been calculated with 0.75 ppm Au, 0.65 wt% Cu, and 0.35 wt% Zn grades. The Say Yayla mineralization consists of massive and semi-massive sulfide minerals and a mineral assemblage represented by predominantly pyrite and chalcopyrite and trace amounts of sphalerite, tennantite and galena. Average base and precious metal grades of the zones occur with >1 wt% Cu are 2 wt% for Cu, 0.7 wt% for Zn, 0.04 wt% for Pb and 1.5 g/t for Au. The sulfur isotope values (δ34S VCDT) range from 4.9‰ to 6.7‰ for pyrite grains and 4.2‰ was obtained from the one sphalerite sample. δ18O values for the quartz from quartz-rich ore samples were 10.6 ‰ and 11.7‰ δ18O (VSMOW) qtz. δ18O (VSMOW) fluid values for the ore-forming fluids vary between 0‰ and 2.4‰. Lead isotope compositions of the pyrite minerals were 18.148–18.150 (206Pb/204Pb), 15.548–15.550 (207Pb/204Pb) and 38.078–38.083 (208Pb/204Pb) The geological, geochemical, and isotopic data of the ore and host-rocks reveal that the mineralization is a bimodal-mafic type (Noranda type), which is classified into Cu-Zn group of volcanogenic massive sulfides. Geochemical and geochronological data from the wall rocks further show that mineralization was developed within an ensimatic island arc environment during the Middle Jurassic. [ABSTRACT FROM AUTHOR]

• The Keban (Cu-Mo)-Pb-Zn skarn deposit is mainly distributed in the contact zone between Permo-Triassic/Permo-Carboniferous metamorphic rocks and Late Cretaceous plutonic rocks. • The geochemical characteristics (major and trace elements) of the Keban pluton comply with the those of Zn-Cu-Mo-W skarn-plutons. • REE geochemistry of the Keban deposit indicates that the fluids have magmatic origin. The Keban-West Euphrates (Cu-Mo)-Pb-Zn skarn deposit occurs mainly around the contact zone of the Permo-Triassic/Permo-Carboniferous metamorphic rocks and Late Cretaceous plutonic rocks in the Eastern Taurus orogenic belt. The skarn formation, in this orogenic belt formed by the Hercynian and Alpine orogenies, is associated with Late Cretaceous alkali syenite intrusion of calcareous rocks. The syenite intrusion is characterised by temporal and spatial zonation, producing several stages of skarnisation. The initial contact metamorphism formed broad halos of hornfels and marble. Subsequent metasomatism by high temperature and hypersaline fluids formed anhydrous calc-silicate assemblages (garnet, pyroxene and wollastonite), partially overprinted by lower temperature and saline fluid hydrous assemblages (epidote, chlorite and calcite) and sulphide minerals (mainly pyrite) as the concentration of sulphur increased. The ore skarn assemblage like pyrite, chalcopyrite, molybdenite, sphalerite, galena, fluorite, magnetite, pyrrhotite, fahlore and native gold occurs as ore minerals, whereas garnet, pyroxene, calcite, epidote, chlorite and quartz constitute the main gangue minerals. The Keban plutonic rocks are syenitic in composition with high contents of Al 2 O 3 , Na 2 O + K 2 O, Zr, Nb, Ta, Th, Rb and rare earth elements (REEs). The major and trace elements composition of the Keban pluton is consistent with those of Zn-Cu-Mo-W skarn plutons. The skarn litho-units show higher concentrations of light REEs compared with heavy REEs. The skarn zone samples display the most prominent REE-enriched pattern, and the depletion pattern in the ore zone is only subordinate to that of the host rock (limestone). The La/Y ratios of the West Euphrates skarns vary from 0.9 to 26.4 with the highest ratios in the ore zone (average = 13.35). The ratios of the plutonic rocks and skarn zones reflect near-neutral to alkali conditions, whereas the ore zone and host rock ratios are characteristic of alkali conditions. The garnet-dominated endoskarn shows high contents of REE (∑REE) compared with the metaluminous syenite porphyry-hosted exhibiting Eu and Ce enrichment, indicating derivation of the magmatic fluids for skarnisation from the alkali syenitic magma. Conversely, the limestones show lower REE concentrations relative to the metaluminous syenite porphyry-hosted rocks. The calcic exoskarn (garnet and clinopyroxene) and ore zone containing high ∑REE, significant positive Eu and Ce anomalies and high Pr/Yb (n) ratios are dominantly of magmatic origin. [ABSTRACT FROM AUTHOR]