Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleYalnız künye2026Natural Radioactivity and Radiological Risk Assessment of Rocks Around the Mines: A Case Study From the Mastra and Hazine Mağara Mining Areas, Northeastern Türkiye
Sipahi, Ferkan; Çelik, Necati; Gücer, Mehmet Ali; Dizman, Serdar
This study presents a comprehensive assessment of natural radioactivity levels and associated radiological hazards in rock samples collected from Mastra and Hazine Mağara mining sites in the Gümüşhane province, Türkiye. The concentrations of primordial radionuclides (226Ra, 232Th, and 40K) were measured in samples of andesite, granite, and limestone using a High Purity Germanium (HPGe) detector. Complementary whole-rock geochemical analysis (XRF and ICP-MS) was conducted to understand the geochemical controls on radioactivity concentrations. The results reveal significant heterogeneity in activity concentrations both within and between the two sites. For 226Ra, the Hazine Mağara site exhibited a wider range (2.44–22.57 Bq kg−1) with a higher maximum value compared to Mastra (2.65–13.96 Bq kg−1). Similarly, 232Th and 40K activity concentrations showed considerable variability, often linked to the presence of specific accessory minerals like zircon, monazite, and K-feldspar. Geochemical data indicated that element concentrations (K, U, Th) were generally lowest in limestone and highest in granite, showing a strong correlation with the measured activity concentration values. Radiological risk indices, including radium equivalent activity, absorbed dose rate, annual effective dose equivalent, and excess lifetime cancer risk, were calculated. While values remain below international public health safety limits, localized anomalies were identified. Multivariate statistical methods were used to determine the relationship between the 226Ra, 232Th, 40K, Raeq (Bq/kg), Ig, Hex, D (nGy/h), AEDE (μSv/y), AGDE (μSv/y), and ELCR (×10−5). The study concludes that despite these localized anomalies, both mining areas pose an overall minimum environmental radiation risk, underscoring the necessity for site-specific assessments to ensure safe resource utilization and radiation protection.
- MakaleYalnız künye2026Who Is at Risk? Analyzing the Drivers of Intimate Partner Violence Against Women in Turkey
Türkkan, Tuğba; Hatipoğlu, Ertuğrul; Yücel, İbrahim; Kulakaç, Nurşen; Sipahi, Ferkan; Zeybek, Halil İbrahim
Violence against women represents a severe violation of human rights and has become a pervasive issue globally. This study aims to examine the risk factors associated with violence against women in a developing country context, specifically Turkey. This study adopted a cross-sectional research design. The study sample comprised 391 women living in a northeastern Turkish province, selected using a stratified sampling method. Participants’ ages ranged from 20 to 60 years, with a mean age of 40.83 years. The findings revealed a positive correlation between the age of both women and their spouses and the likelihood of experiencing physical and verbal violence. Factors such as the number of marriages, duration of marriage, number of children, and spousal infidelity emerged as significant risks for victimization. Additionally, an early age at first marriage, the presence of mental illness, and addiction problems were identified as critical risk factors for women’s victimization in violence. Education and employment were protective factors against violence, with higher educational levels and employment status for women and their spouses reducing the risk. Regression analyses further identified women’s education level, prior exposure to domestic violence, age at first marriage, and the addiction status of the spouse as significant predictors of violence against women. The findings provide valuable insights into the etiology of violence against women. In conclusion, the study has the potential to guide the development of more targeted and effective strategies to combat this pervasive public health and human rights issue.
- MakaleAçık Erişim2025Geçmişten Günümüze Gümüşhane’de Madencilik
Sukuroglu, Ebru Emine; Dağ, Serhat; Alemdag, Selcuk; Saylan, Kemal; Nazir, Bayram; Ozer, Ismail; Kurucu, Muhammet; Sipahi, Ferkan; Atalan, Öznur; Zeybek, Halil
Türkiye, madenler bakımından oldukça çeşitli ve zengin bir ülkedir. Ülkede yer alan bazı madenlerin dünya çapında önemli bir yere sahip olduğu bilinmektedir. Türkiye'nin Doğu Karadeniz bölgesinde bulunan Gümüşhane ili de madenler bakımından zengin bir çeşitliliğe sahiptir. Öyle ki, Gümüşhane’de var olan bu çeşitlilik ilk medeniyetlerin bölgeye hâkim olması ile önemli hâle gelmiş, şehirde bulunan madenlerin dışında şehrin İpek Yolu güzergâhında yer alması da bu bölgenin önemini daha da arttırmıştır. Hiç şüphesiz bu önem, Osmanlı Devleti’nin Trabzon’un fethi ile bölgeyi topraklarına katması ile devam etmiştir. Bu dönem ile birlikte şehirde madencilik faaliyetleri artmaya başlamış ve bu yönde yapılan çalışmalar ülkeye maddi anlamda katkı sağlamıştır. Bu açıdan Osmanlı Devleti, 16., 17. ve 18. yüzyıllarda bünyesinde barındırdığı başta gümüş ve altın madenleri olmak üzere diğer madenlerin varlığı nedeniyle ticari olarak canlı bir özellik gösteren Gümüşhane’ye büyük önem vermiştir. Böylece 17. yüzyılda adeta altın çağını yaşayan maden ocakları, 18. yüzyılın sonlarına kadar faaliyetlerini devam ettirmiştir. Bu yüzyıldan sonra da madenlerde yapılan üretim zamanla azalarak bölgedeki maden işletmelerinde çalışan işçiler madenleri terk etmeye başlamıştır. 19. yüzyılın ortalarına gelindiğinde maden ocaklarının işletilmesinde büyük oranda çözülme ortaya çıkmıştır. Yapılan bu çalışma; Gümüşhane şehrinin tarihî çağlar, Osmanlı Dönemi ve Cumhuriyetten günümüze kadar olan maden çalışmalarını ele alarak şehir ekonomisine birinci derecede yön veren madenlerin şehir açısından önemini ortaya koymayı amaçlamıştır. Çalışmada alan ile ilgili yapılmış çalışmalardan ve arşiv vesikalarından istifade edilmiştir.
- MakaleAçık Erişim2025Mescitli Formasyonu’na (Gümüşhane, Türkiye) ait kumtaşlarının endüstriyel hammadde olarak kullanım potansiyelinin incelenmesi
Aliyazıcıoğlu, Şener; Dağ, Serhat; Zeybek, Halil İbrahim; Çavuşoğlu, İbrahim; Gücer, Mehmet Ali; Sipahi, Ferkan; Dokuz, Abdurrahman
Doğal zenginliklerin ortaya çıkarılması ve yöresel kayaçların ekonomiye kazandırılarak endüstriyel kullanım alanlarının belirlenmesi günümüzde büyük önem taşımaktadır. Bu çalışmada, Gümüşhane’deki Mescitli Formasyonu kumtaşlarının endüstriyel hammadde olarak kullanım potansiyeli araştırılmıştır. Kumtaşları başlıca monokristalin ve polikristalin kuvars, feldispat, volkanik ve tortul kayaç parçaları, opak mineral, kil matriks ve az oranda bağlayıcı karbonat/silis minerali içermektedir. Grovak (psammit) olarak sınıflandırılan kumtaşlarının kimyasal ayrışma indeksi (CIA) parametresine göre alterasyondan çok fazla etkilenmediği belirlenmiştir. Jeoteknik özellikler açısından, ortalama kuru yoğunluk 2.48 gr/cm3, doygun yoğunluk 2.54 gr/cm3, gözeneklilik %6.63 boşluk oranı %7.11, ultrasonik P-dalga hızı 4793 m/sn, tek eksenli basınç dayanımı 103.09 MPa ve dolaylı çekme dayanımı 5,86 MPa olarak belirlenmiştir. Donma-çözünme deneyi ile don kaybı %1.19 olarak belirlenmiş, 600-800ºC sıcaklıklara kadar ısıtılan kumtaşı numunelerinde ortalama 9.8 gr ve 17.9 gr kütle kaybı gözlenmiştir. Aynı sıcaklık koşullarında kumtaşlarının dayanımının sıra ile %7.64 ve %15.17 oranında azaldığı görülmüştür. Hücre Sitotoksisite analizlerinde toksik etkiye rastlanmamıştır. Sonuçlar, kumtaşlarının günlenmeye maruz kalacak alanlarda kullanım için uygun olmadığı, bina içyapı ve dekoratif amaçlı kaplamalarda kullanılabileceğini göstermiştir. Sıcaklık dayanımı ve hücre sitotoksisite analizleri ise kumtaşlarının ızgara taşı olarak kullanılabileceğini ortaya koymuştur.
- MakaleAçık Erişim2025Granodiyorit atıklarının demir oksitli sırlarda kullanımının araştırılması: estetik ve sürdürülebilirlik perspektifi
Arıanpour, Aslı Çakır; Gücer, Mehmet Ali; Isiktas, Imre Deniz; Özek, Serap Bedel; Helvacıkara, Fidan Tonza; Sipahi, Ferkan
Seramik üretimi, doğal hammaddelere dayalı çok aşamalı süreçler gerektirir. Ancak artan çevresel kaygılar ve hammadde kaynakların tükenmesi, alternatif hammadde arayışını ve atık yönetimini seramik endüstrisinin öncelikli konuları haline getirmiştir. Özellikle doğal taş endüstrisinde oluşan atıklar hem çevresel etkilerin azaltılması hem de ekonomik değer yaratılması açısından önemli fırsatlar sunmaktadır. Bu bağlamda, granitoyidik kayaçlar, özellikle demir oksit içeriği sayesinde seramik sırlarında estetik ve işlevsel katkı sağlayabilecek potansiyel bir atık malzeme olarak değerlendirilmiş ve Gümüşhane il merkezindeki bir mermer işletmesinden temin edilen granodiyorit atıklar, demir oksitli sırların renklendirici bileşeni olarak kullanılmıştır. Petrografik analizler sonucunda kayaç numuneleri granodiyorit, diyorit ve granit olarak sınıflandırılmış; özellikle biyotit ve hornblend gibi mafik mineralleri yüksek oranda içeren granodiyorit (H1) örneklerinde toplam Fe₂O₃ oranının %3,96 olduğu belirlenmiştir. Bu nedenle sır formülasyonlarında granodiyorit örneği esas alınmıştır. Beş farklı seramik bünye (kırmızı, şamot, döküm, porselen ve stoneware) üzerine uygulanan granodiyorit katkılı sırlar 1040°C–1100°C aralığında pişirilmiş ve özellikle aventurin etkili yüzeyler elde edilmiştir. Denemeler sonucunda, granodiyorit atıklarının sır yüzey özelliklerini, renklenme karakterini ve estetik niteliklerini olumlu yönde etkilediği gözlemlenmiştir. Elde edilen veriler, bu atık malzemenin seramik sektöründe hem sürdürülebilirlik hem de estetik çeşitlilik açısından değerli bir alternatif sunduğunu göstermektedir.
- MakaleYalnız künye2025Origin and tectonic setting of the carbonate-hosted Kopuz Fe skarn Deposit, Sakarya Zone, NE Türkiye
Sipahi, Ferkan; Akpınar, İbrahim; Gücer, Mehmet Ali; Kaygusuz, Abdullah; Vural, Alaaddin; Saydam Eker, Çiğdem
The Kopuz Fe skarn deposit in the eastern Sakarya Zone is genetically associated with the 44–45 Ma Kopuz granitoid. The Fe ores are hosted within the contact zone between this granitoid and Jurassic Lower Cretaceous limestone. The deposit is characterized by both endo- and exoskarn zones, which exhibit a diverse range of minerals including clinopyroxene, plagioclase, amphibole, biotite, garnet, epidote, phlogopite, magnetite, hematite, pyrite, quartz, calcite, actinolite, limonite, and goethite. Magnetite and hematite, accompanied by small amounts of pyrite, are primarily ore minerals. Pyroxene types observed in the mineralization include diopsidic hedenbergite in the endoskarn zone and diopside in the exoskarn zone. Plagioclase in the endoskarn zone vary from oligoclase to Labrador in composition, which transition towards Na-rich plagioclase and orthoclase in the ore-bearing exoskarn zone. Amphiboles, primarily calcic in nature, are classified as Mg-hornblende and actinolite, with low F and Cl contents, indicating minimal F enrichment during Fe-skarn formation. Garnet is characterized by andradite in the exoskarn zone close to the endoskarn and grossular-andradite in the distal exoskarn zone. The increase of Ad/Gr ratios in zoned garnet indicate an increasing ƒO2 value outward from it. Considering that rare pyrite occur together with magnetite and hematite, we suggest that the deposit formed under conditions of low ƒS2 and high ƒO2 conditions. The homogenization temperature and salinity of the fluid inclusions in quartz from the exoskarn zone vary from 224 °C to 349 °C and 4.18 % (wt% NaCl equiv.), respectively. The oxygen isotope composition (5.10 ‰ to 7.86 ‰) of the fluids in equilibrium with magnetite and quartz minerals in the exoskarn zone supports a magmatic fluid origin. The oxygen isotopic signatures of epidote and amphibole further indicate a minor interaction with an additional source, likely meteoric waters. The sulfur isotope composition of pyrite (2.3 ‰) is consistent with a magmatic sulfur source. In summary, the middle Eocene-aged Kopuz Fe skarn deposit occurred a shallow depth within a magmatic arc, where oxidized conditions predominated.
- MakaleAçık Erişim2024Comparison with carbonate rocks hosted iron skarn in the eastern Sakarya Zone (Gümüşhane, NE Turkey): a geomorphologic, geochemical and stable isotopic approach
Sipahi, Ferkan; Zeybek, Halil İbrahim; Gücer, Mehmet Ali; Işık, Fatih
The carbonate rocks in the eastern part of NE Turkey are situated within the Pontide paleo-magmatic arc and are frequently in contact with granitoid formations, often hosting skarn mineralization in the region. These carbonate rocks, typically found on ridges and hillsides exhibit predominant orientations along east–west, northeast-southwest, and northwest-southeast directions. A part of limestone, named as biomicrite, metamorphosed and display a saccharoidal texture. Comprised mainly of calcite, with less secondary quartz and iron oxide minerals, these carbonate rocks are classified as Fe-poor calcio-carbonate and magnesio-carbonate, having higher CaO and LOI contents. Marble and recrystallized limestone with granoblastic texture mainly comprise of calcite, less quartz, magnetite, and hematite. Marble classification diagrams suggest calcic skarn mineralization, indicated by decreasing CaO (or CO2) and increasing MgO from limestone to marble (or skarn). Strontium contents deviate slightly from the lithosphere carbonate average, while low Rb contents, attributed to skarn metamorphism, indicate the absence of K-bearing minerals. The high Al2O3/SiO2 in the carbonate rocks can points out hydrothermal activity and carbonate disengagement can indicate to actualize at temperatures that can affect Ce and Al mobilities. The low authigenic U value, low U/Th and Ni/Co ratios in carbonate rocks have been implied that protolith constituents deposited under oxic conditions. Positive Eu anomalies in limestone and marble suggest the influence of hydrothermal fluids. Carbon and oxygen isotope values in marble are similar with those of metamorphic and skarn marbles, indicating a magmatic origin. Overall, mineralogical and geochemical analyses propose a uniform source and/or geological process for all studied marbles.
- MakaleYalnız künye2023The Sr, Nd, Pb and Hf isotopes and crystallization conditions of the middle Eocene Daǧdibi Pluton in the eastern Sakarya Zone, Turkey
Sipahi, Ferkan; Gücer, Mehmet Ali; Dokuz, Abdurrahman; Yi, Keewook; Kaygusuz, Abdullah; Akaryall, Enver; Saydam Eker, Çiǧdem; Doruk, Cüneyt
Magmatic activity in the Sakarya Zone, an important segment of the Alpine orogenic belt, continues intermittently from the middle Carboniferous to Miocene. In this study, we provide geochronological and geochemical data from the Daǧdibi Pluton in the eastern Sakarya Zone to present some inferences on the source region and petrogenesis of the middle Eocene magmatism. U-Pb zircon geochronology from two granodiorite samples gives middle Eocene ages of 44.75 ± 0.92 and 45.01 ± 0.59 Ma. The pluton is mainly composed of K-feldspar, plagioclase, quartz, Mg-hornblende/actinolite, Fe-Ti oxides and small amounts of biotite, and secondary chlorite and epidote. Parental magma of the intrusive rocks has a high-K calc-alkaline affinity with metaluminous character. The oxygen fugacity values vary between -18 and -17. The rocks show slightly radiogenic 87Sr/86Sr(i) (0.704845-0.705726) ratios and μNdi values between -0.96 and +0.52. Pb-Pb isotope ratios are typical for those of the lower continental crust. μHf(i) values of the zircons range from 0.14 to 10.26. The geochemical and isotopic features of the pluton point to a parental magma derived from a depleted mantle that was metasomatized by fluids during previous subduction events. The volumetric abundances of the rock types are decreased as the silica content increase, implying that the fractional crystallization is the most important process during the formation of the present compositional range of the pluton. Amphibole, plagioclase and Fe-Ti oxides are the fractionated phases while K-feldspar is largely accumulated. In the light of the data presented above, slab breakoff is regarded as the geodynamic process responsible for the formation of the Daǧdibi Pluton in the middle Eocene.
- MakaleAçık Erişim2023A study on the magnetite skarn mineralization (Gümüşhane, Türkiye): a magnetic survey
Sipahi, Ferkan; Sadiklar, M. Burhan; Gücer, Mehmet Ali; Aydin, Ali; Kara, Rasim Taylan
Iron (Fe)-skarn mineralizations (Çambaşı, Dereli, Eğrikar, Karadağ, Kopuz, Sekü, Donguldere, Arnastal, Özdil, Ögene, İkizdere, Ovit Dağı, Kartiba, etc.) in the eastern part of the Pontides (NE Türkiye) are accommodated in the Pontide paleomagmatic arc and the eastern part of the Pontides Metallogenic Belt containing numerous various deposits. Fe-skarn mineralization around the Arnastal Plateau (Gümüşhane-Türkiye) is fragmentary in this area, which is covered with plants (grasses, flowers, etc.). Thus, it was attempted to describe the subsurface structures and Fe mineralization using an interpretation of the available geological and existing magnetic data in this area. Granitoid and volcano-sedimentary series (Upper Cretaceous) outcrop in the study area. These volcanosedimentary series consist of limestone, sandy limestone, marl, andesite, quartz andesite, basalt, and their equivalent pyroclastics. They include a thin layer of the red limestone (Upper Cretaceous) and olistolith recrystallized limestones (Jurassic-Lower Cretaceous). Zigana granitoid, intruding into all of these rocks, is high-K calc-alkaline and metaluminous and is classified as quartz monzonite, monzogranite, granite, and syenogranite as a result of its modal composition. Contact pyrometasomatic mineralization occurs in between the limestone and granitoids in the Arnastal Plateau. In addition to petrographic and mineralogical studies, magnetic methods were applied to an area of approximately 10 km2 to find any covered Fe deposits. Magnetic susceptibility values measured on the outcropped rocks ranged from 1 to 34 (10–7 SI) for limestone, 78 to 3750 (10–7 SI) for basalt, and 105 to 3946 (10–7 SI) for granitoids. It is considered that these ranges express the alteration (physical or chemical) of the rocks, their homogeneity, and the lack or presence of Fe minerals. The magnetic survey was conducted along a study area measuring 12,075 m long with 25 and/or 50 m station spacing. Processing of the magnetic data revealed the presence of eight buried Fe ores that could represent either massive or disseminated mineralization between the Sarıtaş and Kurtdere plateaus. Magnetite ore bodies may be present from the surface to a depth of approximately 15–25 m inside the limestone. In addition to the identification of new magnetite ore mineralization or bodies, a new geological map was designed by determining probable formation boundaries with this magnetic survey.
- MakaleYalnız künye2022Gümüşhane Üniversitesinin Dijital Dönüşüm ve Covid-19 Pandemisine İlişkin Çalışmalarının Değerlendirilmesi
Çam, Handan; Çakır, Günay; Zeybek, Halil İbrahim; Sipahi, Ferkan
Dünya, 2019 yılında ortaya çıkan ve 2020 yılı başında pandemiye dönüşen SARS-CoV virüs salgını ile mücadele etmeye başlamış ve salgın tüm yaşam biçimimizi etkilemiştir. Bu zorlu süreçte tüm insanlık bir arada savaş vermek zorunda kalmıştır. Salgından önce teknolojik gelişmeler ve çevresel kirlilikler hayatımızın her alanında etkili olmaya başlamışken, salgınla eğitimde de radikal değişiklikler olmuştur. Ülkemizde salgın öncesi az sayıda üniversite uzaktan eğitimde ön planda yer almıştır. Yükseköğretim Kurulu, pandemiden önce, üniversitelerde dijital teknoloji kullanımını yaygınlaştırma stratejisi ile geleceği görerek etkili bir adım atmış ve “Yükseköğrenimde Dijital Dönüşüm Projesi” başlatmıştır. Bilgi teknolojileri kullanımının yaygınlaşması, öğrenme tekniklerinin değişmesi, toplumsal istekler, öğrenen/öğreten profili ve son olarak pandemi, dijital dönüşümde etkili olmuştur. Dijital dönüşümün gerekliliği, pandemi döneminde daha belirgin şekilde anlaşılmıştır ve yaşanılan zorluklar, toplumlarda farklı eğilimlerin daha hızlı benimsenmesine neden olmuştur. Gümüşhane Üniversitesi de Yükseköğretim Kurulu’nun 2018 yılında başlattığı Dijital Dönüşüm Projesi’ne ikinci aşamada dahil olmuştur. Bu çalışmanın ana amacı da Gümüşhane Üniversitesinin COVID-19 pandemisi dönemindeki dijital dönüşüm ve pandemi odaklı çalışmaların bir kısmını değerlendirmektir. Sonuç olarak, Gümüşhane Üniversitesinin pandemi süreci boyunca oldukça başarılı faaliyetler yürütmüş ve dijitalleşmeyi eğitimin her alanına yaymak adına önemli çabalar sarf etmiştir.
- MakaleAçık Erişim2022Gold Mining, History and Today: The Case of Gümüşhane
Zeybek, Halil İbrahim; Akaryali, Enver; Çavuşoğlu, İbrahim; Gücer, Mehmet Ali; Sipahi, Ferkan
As in the history of humanity, the need for mines, causing important developments in human life, is gradually increasing. The mines, whose names are given to historical ages, have been a necessary source of raw materials for human beings to survive. Mines are one of the factors that directly affect the country's economy. Gold is a mine whose history is based on ancient history, its production has gained importance especially in recent years as a result of increasing demand and the research for new gold sources. Türkiye is a rich country with a 2% share in the world, with gold deposits of different geological characteristics and 431 ton reserves. Depending on the gold mining in recent years, gold explorations in Türkiye continue intensively and the annual gold production has increased to 39 tons in 2021. It has been determined that gold mining is concentrated in the Aegean and Marmara Regions with the Eastern Black Sea part in Türkiye. Gümüşhane is one of the provinces where gold mining is intense. In this study, the gold mining and importance in Gümüşhane are discussed by giving information about the history of gold mining.
- MakaleYalnız künye2022Eocene magmatism and associated Fe-Cu mineralization in northeastern Turkey: a case study of the Karadağ skarn
Sipahi, Ferkan; Saydam Eker, Çiğdem; Akpınar, İbrahim; Gücer, Mehmet Ali; Vural, Alaaddin; Kaygusuz, Abdullah; Aydurmuş, Tanju
The metallogenic belt containing numerous skarn mineralized systems starting from Eastern Europe continues through Turkey and Iran. The study area in the Eastern Pontides is within this metallogenic belt. The 44.39 ± 0.53 Ma Karadağ Intrusion sourced skarn mineralization is located along the granitoid-to-limestone contact. The Karadağ Intrusion is an arc-like pluton with medium–high K calc-alkaline and peraluminous–metaluminous affinity. The Karadağ Fe–Cu skarn mineralization (Gümüşhane, Turkey), an exoskarn, is hosted by Late Cretaceous limestone and consists of early garnet, clinopyroxene, and orthoclase with late epidote and chlorite. Primary ore minerals are magnetite and haematite, accompanied by minor amounts of chalcopyrite and pyrite. Pyroxene comprises mostly diopside and less hedenbergitic diopside and johannsenite. Wollastonite is very rare. Garnet is andradite and grossular–andradite. Thus, all these results imply that the Karadağ Fe–Cu skarn mineralization formed under relatively oxidized and Fe-rich conditions. The homogenization temperatures of the fluid inclusions vary from 189°C to 405°C for quartz and 186°C to 430°C for calcite. The salinity contents in the fluid inclusions are within 0.2–9 wt% NaCl equivalent for quartz and 0.4–14.8 wt% NaCl equivalent for calcite. First melting temperatures between −36.5 and −47.4°C were attained with the presence of NaCl–FeCl2± CaCl2 in the initial phase of fluid inclusions. The first melting in the later stage of fluid inclusions is between −3.8 and −17.2°C, thereby, supporting the existence of NaHCO3-Na2CO3-KCl-type salt composition. The δ18O values of minerals are 1.7–10.3‰ for garnet, 11.1–14.6‰ for quartz, 6.4 to 6.8‰ for epidote, and 2.8–3.8‰ for magnetite in the Karadağ skarn mineralization. The δ18O value of epidote indicates magmatic fluid, whereas those of garnet, magnetite, and quartz suggest magmatic fluids together with less meteoric effect. The δ18O values in limestone (18.7 to 22.3‰), marble (8.7‰), and calcite (10.5 to 12.2‰) were depleted relative to typical δ18O contents of marine carbonates (20 to 30‰). Moreover, the C isotope values of calcite (−5.4 to −1.4‰), marble (−2.1‰), and limestone (1.0 to 1.2‰) reflect those of metamorphic rocks and skarns (−4.0 to 3‰ and −18 to 2‰). Mineral paragenesis, fluid inclusion, and stable isotopic signatures are consistent with ore mineralization caused by the interaction of magmatic fluids with carbonate host rocks. Karadağ Fe-Cu skarn mineralization, associated with Karadağ postcollisional magmatism, is an example of skarn mineralized system in the Eastern Pontides.
- MakaleYalnız künye2021Mineralogical and Chemical Characteristics of Clay Areas, Gümüşhane Region (NE Turkey), and Their Detection Using the Crósta Technique with Landsat 7 and 8 Images
Vural, Alaaddin; Akpinar, İbrahim; Sipahi, Ferkan
The clay areas in Gümüşhane (NE Turkey) were examined in mineralogical and geochemical terms, and by remote sensing methods. X-ray diffraction, scanning electron microscope and chemical analysis were completed on samples from 11 selected clay areas in the region. Within the scope of remote sensing, Landsat 7 and 8 satellite images of the region were processed with the Crósta technique to assess the clay areas. The Kale and Tamzı clays are contained within a Late Cretaceous turbiditic series. The clays in Canca, Refene and Çamlıca occur in intensively hydrothermally altered volcanic rocks of the Eocene Alibaba Formation. The other clay areas are in the Liassic Şenköy Formation consisting of a volcano-sedimentary series. The clays in the Şenköy Formation are generally below the coal levels. While mainly illite and lesser kaolinite were determined in Dörtkonak, Alemdar, Yukarı Kov and Çamlıca, the clays in Tahnis and Kabantaşı are smectite. Tekke, Canca and Refene clays are kaolinite with smaller amounts of illite, whereas Kale and Tamzı clays are mainly chlorite with lower content of illite–smectite interlayers. Illites in Dörtkonak, Alemdar, Yukarı Kov and Çamlıca are poor in iron and magnesium and formed by hydrothermal alteration of feldspars in the host rocks. Findings of the remote sensing studies using Landsat 7 and 8 datasets were compatible with the results obtained from field observations and general geological studies, and so it is concluded that the Crósta technique provided good results for exploration of clay occurrences and their determination in the region.
- MakaleYalnız künye2020Eocene I-type magmatism in the Eastern Pontides, NE Turkey: insights into magma genesis and magma-tectonic evolution from whole-rock geochemistry, geochronology and isotope systematics
Kaygusuz, Abdullah; Yücel, Cem; Arslan, Mehmet; Temizel, İrfan; Yi, Keewook; Jeong, Youn-Joong; Siebel, Wolfgang; Sipahi, Ferkan
The Eastern Pontides orogenic belt in NE Turkey hosts numerous I-type plutons of Eocene epoch. Here, we report new U–Pb SHRIMP zircon ages and in situ zircon Lu-Hf isotopes along with bulk-rock geochemical and Sr-Nd-Pb-O isotope data from the Kemerlikdağı, Aydıntepe and Pelitli plutons and mafic microgranular enclaves (MMEs) to constrain their parental melt source(s) and evolutionary processes. U-Pb SHRIMP zircon dating yielded crystallization ages between 45 and 44 Ma for the studied plutons and their MMEs. The plutons range from gabbro to granite and have I-type, medium to high-K calc-alkaline, and metaluminous to slightly peraluminous characteristics. On the primitive mantle-normalized multi-trace-element variations, the plutons and their MMEs are characterized by significant enrichment in LILE/HFSE. Chondrite-normalized REE patterns of the plutons and their MMEs are close to each other and show moderate enrichment with variable negative Eu anomalies. The studied plutons have fairly homogeneous isotope composition (87Sr/86Sr(i) = 0.70502 to 0.70560; εNd(i) = +0.9 to–1.4; δ18O = +5.0 to +8.7‰, εHf(i) =–2.2 to +13.5). The MMEs show medium to high-K calc-alkaline and metaluminous character. Although the isotope signatures of the MMEs (87Sr/86Sr(i) = 0.70508 to 0.70542; εNd(i) = +0.9 to −1.1; δ18O = +5.8 to +8.0, εHf(i) = +4.3 to +10.4) are very similar to those of the host rocks. Fractionation of plagioclase, amphibole, pyroxene and Fe-Ti oxides played an important role in the evolution of the plutons. The isotopic composition of the studied plutons and MMEs are similar to I-type plutons derived from mantle sources. The MMEs show incomplete magma mixing/mingling, representing small bodies of mafic parental magma. The parental magma(s) of the studied plutons were generated from the enriched lithospheric mantle and then modified by fractional crystallisation, and lesser assimilation and mixing/mingling in the crustal magma chambers.
- MakaleAçık Erişim2020Nature of clays in late cretaceous dacitic rocks in the eastern sakarya zone (Ne turkey): A geochemical and isotopic approach
Sipahi, Ferkan; Gücer, Mehmet Ali; Sadiklar, Münür Burhan
Late Cretaceous felsic rocks are common in the eastern Pontides (NE Turkey). These rocks developed as an island arc from the Jurassic to the Miocene; they also host numerous volcanogenic massive sulfide deposits. The Late Cretaceous dacites that outcrop around Zigana Mountain (Gümüşhane, NE Turkey) were exposed to intensive hydrothermal alteration. Widespread hydrothermal alteration of Late Cretaceous dacite in Zigana Mountain has led to the formation of well-developed clay minerals. Their main alteration products are sericite, chlorite, and carbonates (ankerite and calcite). The clay minerals identified by X-ray diffraction and differential thermal analysis include illite, chlorite, small amounts of kaolinite, and smectite. The polytype of illite is 2M1. Illites formed as a result of hydrothermal alteration of feldspars; they are also Fe-and Mg-poor. Chlorite is characterized by decreasing Fe/(Fe+ Mg) ratio with increasing alteration grade and has a trioctahedral structure. Chlorite geothermometer calculations (100–300°C) reflect the activities of hydrothermal solutions. Chlorite forms in more alkaline conditions compared with illite, as its formation is associated with the presence of carbonates. Oxygen and hydrogen stable isotope values, K-Ar dating of illites, and textural and chemical evidence suggest that clays might have formed mainly by alteration of minerals in dacitic rocks with hydrothermal fluids of magmatic origin during the Campanian under acidic–weak alkaline conditions.
- MakaleYalnız künye2020Geochemical composition of magnetite from different iron skarn mineralizations in NE Turkey: implication for source of ore-forming fluids
Sipahi, Ferkan; Gücer, Mehmet Ali; Saydam Eker, Çiğdem
Iron oxide mineralizations in the eastern part of the Pontides (NE Turkey) are hosted in the skarn environments which are the Pontide paleomagmatic arc. These mineralizations always occur in the contacts between granitoid and limestone. Magnetites are hosted in carbonate rocks and generally formed during garnet-magnetite-epidote-quartz phase. Magnetites have high Co (15.8–43.4 ppm for the Kopuz, 11–12.5 ppm for the Eğrikar, and 3.8–1266.7 ppm for the Karadağ) concentrations suggesting that the sulfide decreased from the early to the late phases in the iron skarn mineralization forming systems. The Co/Ni ratios in the magnetites (0.12 to 35.38 for Karadağ, 2.19 to 13.53 for the Kopuz, and 2.39 to 5.21 for the Eğrikar) show the hydrothermal effect on the magmatic source in iron skarns in the study area. Thus, variable Co/Ni ratios reflect interactions between the magma with the host rock during successive alteration stages. Magnetites in this study have Sc-Nb-Mg-Ti depletions and Ta enrichment. In this study, high Co, Ti, and V contents in magnetites suggest the high temperature (300–500 °C) and low ƒO2. The V contents of the magnetite in the Karadağ increase with the decreasing oxygen fugacity of fluid(s) forming magnetites, whereas the V contents of the magnetites in the Kopuz and Eğrikar decrease with increasing oxygen fugacity of fluid(s) forming magnetites. Element patterns and Ni/Cr ratio (< 1) of the magnetite are geochemically similar to those of magnetite in Fe-skarn deposits and partly magmatic accessory magnetite of I-type granites. As a result, the Co, Ni, V, and Ti elements of the magnetite have played an important role in the discriminating and interpreting of skarn mineralizations in the eastern Pontides and support a calcic skarn origin with studies of the mineralization geology.
- MakaleAçık Erişim2019Zigana Dağı (Gümüşhane, KD Türkiye) Dayklarının Jeokimyası ve Jeolojik Anlamı
Sadıklar, Münür Burhan; Gücer, Mehmet Ali; Sipahi, Ferkan
Eski bir magmatik yay olan Doğu Karadeniz Bölgesi (Pontidler) Sakarya Zonu içindeyer alan andezit ve porfirik dasit daykları Geç Kretase yaşlı volkanitleri kesmektedir.Andezit ve porfirik dasit daykları porfirik doku sergilemektedir. Andezitler başlıcaplajiyoklas ve ojit minerallerinden ibaret olup, plajiyoklaslar elek dokusu ve polisentetik ikizlenme göstermektedir. Ojit minerallerinin kenar kısımlarında opak mineral oluşumları yaygındır. Porfirik dasitler ise kuvars, plajiyoklas, amfibol ve biyotit minerallerinden oluşmakta olup, kuvars kristallerinin kenarları kısmen yenmiştir. Plajiyoklaslar yaygın olarak serizitleşmiş, daha az oranda kalsitleşmiştir. Amfiboller hidrotermal ayrışma sonucu klorit, karbonat (kalsit ve ankerit) ve opak minerallere, biyotitler ise genel olarak kloritlere dönüşmüştür. Ana oksit ve iz element değişim diyagramlarındaki düzgün yönsemeleri ve mineral ayrımlaşma diyagramlarındaki durumları, daykların gelişiminde fraksiyonel kristalleşmenin etkili olduğunu göstermektedir. Plajiyoklas ve ojit ayrımlaşmasının andezit daykların gelişiminde, hornblend ve plajiyoklas ayrımlaşmasının ise porfirik dasitlerin gelişiminde etkili olduğu belirlenmiştir. Zenginleşmiş okyanus ortası sırtı bazaltlara (Z-OOSB) göre normalleştirilmiş iz element diyagramında negatif Nb, P2O5 ve TiO2 anomalileri olup, büyük iyon çaplı elementler (BİYE) yüksek çekim alanlı elementlere (YÇAE) nazaran daha fazla zenginleşmiştir. Düşük Nb/U ile yüksek La/Nb ve Th/Nb oranları, andezit ve porfirik dasit dayklarının kıtasal kabuk kirlenmesinden etkilendiğini belirtmektedir. Sonuç olarak, daykların yay ortamında, Geç Kretase sonlarına doğru benzer kökenli ve yitim ilişkili metasomatize olmuş bir manto kaynağından türemiş oldukları düşünülmektedir.
- MakaleYalnız künye2019Nature of tourmaline formation in quartz porphyry in the E Sakarya zone (NE Turkey): Geochemistry and isotopic approach
Sipahi, Ferkan
Tourmaline, which exhibits important differences in terms of texture and composition, is found in 44 My aged quartz porphyry from Karadağ in the eastern Pontide (NE Turkey). Tourmaline has high Al and Mg contents and is the chemical zoning; it contains Mg that can substitute for Fe and/or Al in the Y site and X-vacancy that can replace Na in the X site from the core to rim. Tourmaline, classified as dravite component, has low Fe content and very low Ca content. The V (112-510 ppm) and Sr (37.3-147.1 ppm) contents of tourmalines related to quartz porphyry are in conformity with metamorphic and magmatic tourmalines. Tourmalines have similar rare earth elements (REEs) but lower heavy REE contents than host quartz porphyry. The δ18O and δD values of tourmalines are relatively narrow, ranging from 5.7 to 8.5% V-SMOW and from -58 to -72% V-SMOW, respectively, consistent with primary magmatic water. The oxygen-isotope thermometry calculation of quartz and tourmaline pair yields equilibrium formation temperature of 432 °C. The formation of tourmaline shows a post magmatic origin, confirming magmatic fluid cooling and fluid-rock interactions.
- Proje2018Doğu Pontid Güney Zonu’ndaki (Bayburt) Tersiyer yaşlıintruzif kayaçların Petrokimyası, Jeokronolojisi ve İzotopSistematikleri
Çakmak, Gökhan; Temizel, İrfan; Kaygusuz, Abdullah; Arslan, Mehmet; Sipahi, Ferkan
Doğu Pontid güney zonunda (Bayburt) Eosen yaşlı intrüzif kayaçlar bulunmaktadır. Bu bölgede, bugüne kadar yaşları kesin olarak tanımlanamayan sokulumların ve içlerindeki mafik mikrogranüler anklavlar (MMA)?ın mineralojik bileşimleri, tüm kayaç jeokimyasal, Sr-Nd-Pb-O izotopik özellikleri ve radyometrik yaşları ortaya konulmuştur. İncelenen plütonik kayaçların U Pb SHRIMP zirkon yaşları 43.14 ± 0.54 ila 45.81 ± 0.48 My arasında değişir. Bu kayaçlar yaklaşık KD-GB uzanımlı olup, boyutları 3-22 km2 arasında değişir. Bileşimleri diyoritten granite kadar değişmekte olup, başlıca mineralleri plajiyoklas (An02-68), ortoklas (Or01-96), amfibol (Mg#=0.03-0.93), kuvars, biyotit (Mg#=0.49-0.62), piroksen (En37-57 Fs12-45 Wo2- 48), magnetit ve ilmenit oluşturur. Genel olarak I-tipi, düşük-yüksek K?lu kalk-alkali, genellikle metalümin az oranda da peralümin karakterlidirler. Kondirite göre normalleştirilmiş nadir toprak element dağılımları konkav şekilli (LaN/LuN=2.53?12.22) olup, negatif Eu anomalisi (Eu/Eu*=0.31?0.92) gösterirler. Ana ve iz element değişimleri, kayaçların gelişiminde plajiyoklas, amfibol, piroksen ve Fe-Ti oksit fraksiyonlaşmasının etkili olduğunu gösterir. Kayaçların ?Nd(i) değerleri ?1.34 ve 0.92, 87Sr/86Sr(i) değerleri 0.7049 ve 0.7056 arasındadır. 206Pb/204Pb(i), 207Pb/204Pb(i) ve 208Pb/204Pb(i) içerikleri sırasıyla 18.43?18.69, 15.59?15.63 ve 38.44?38.83 arasındadır. İncelenen örneklerdeki ?18O değerleri ? 4.8 ila ? 8.8 arasında olup, I-tipi granitoyidlere benzer bileşime sahiptirler. Tüm veriler, incelenen plütonik kayaçların ana magmasının litosferik mantodan türediğini, kabuksal kayaçların katkısının nisbeten az olduğunu gösterir. İncelenen plütonik kayaçların içindeki MMA?lar diyorit, gabrodiyorit ve tonalit bileşimli olup, orta-yüksek K?lu metalümin karakterde ve ana kayadan daha düşük A/CNK (0.77-0.97) ve SiO2 (% 55-64) ve daha yüksek Na2O/K2O (4.9-7.2) oranlarına sahiptirler. İzotopik özellikleri dikkate alındığında, MMA?lar ana kayaçlara benzer Sr-Nd-Pb-O izotopik bileşimlere sahip olup, onlara nazaran daha düşük 143Nd/144Nd(i) (0.51253-0.51263) ve ?18O (6.1-7.4) değerlerine sahiptirler. Tüm bu veriler dikkate alındığında, MMA?lar ana kaya içerisinde soğumuş olan eş yaşlı mafik magmanın küçük kütlelerini temsil eden magma karışım ürünleri olarak kabul edilebilirler. İncelenen plütonlar ve içlerindeki MMA?larda hesaplanan kristalizasyon basınçları birbirine yakın değerlerde olup, ana kayaçlarda 0.1?2.6 kbar, MMA?larda ise 0.1?2.9 kbar arasındadır. Kristallenme sıcaklıkları ise ana kayaçlarda 506-1172 °C, MMA?larda ise 467-1155 °C arasında değişmektedir. Tüm bu veriler Eosen yaşlı plütonik kayaçların nisbeten sığ derinliklere (~ 5 to 9 km) yerleşmiş olduklarını ifade eder.
- MakaleAçık Erişim2018Petrography, mineral chemistry and crystallization conditions of cenozoic plutonic rocks located to the north of Bayburt (Eastern Pontides, Turkey)
Kaygusuz, Abdullah; Yücel, Cem; Arslan, Mehmet; Sipahi, Ferkan; Temizel, Irfan; Çakmak, Gökhan; Güloglu, Z. Samet
The Eastern Pontides comprise many intrusive bodies varying in composition, size and age from Palaeozoic to Cenozoic. Especially Cenozoic aged bodies are commonly observed in the southern part, while they are rarely exposed in the northern part of the Eastern Pontides. In this study, the petrography and mineral chemistry of the Cenozoic aged Çiçekli, Somarova, Sorkunlu, Şaşurluk, Aydintepe, Kemerlikdagi and Pelitli plutons located to the north of Bayburt are determined, and the crystallisation conditions of the studied bodies were estimated by means of thermobarometer calculations. The studied plutons extend mostly in NE-SW directions and are approximately ellipsoid in shape. The contacts between the plutons and surrounding rocks are sharp, and plutons commonly contain mafic microgranular enclaves (MMEs) of different sizes. Petrographic and mineral chemistry studies reveal some disequilibrium textures reflecting the magma mixing process. Based on modal mineralogy, the plutonic rocks are gabbroic diorite, diorite, tonalite, granodiorite and monzogranite in composition. The rocks have fine to medium granular, porphyric, monzonitic, poikilitic, occasionally myrmekitic and micrographic textures. The main minerals are labradorite and albite (An68-02), magnesiohornblende and actinolite (Mg# = 0.6-0.9), diopside and augite (Wo44-46), clinoenstatite (En53-57) and Fe-Ti oxide minerals. Crystallization temperatures calculated from amphibole, biotite, clinopyroxene, magnetite and ilmenite minerals are 405°C to 1161°C, pressure values are 0.1 to 2.7 kbar, and oxygen fugacity (log10 fO2) is -20 to -12. Estimation of water content calculated by using amphiboles is between 2.9 and 6.8%. Based on obtained data, it is suggested that the studied plutons were emplaced at shallow depths (∼ 1-8 km).