Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Kaygusuz, Abdullah(8)
- Sipahi, Ferkan(6)
- Eyuboglu, Yener(5)
- Santosh, M.(5)
- Arslan, Mehmet(4)
- Chung, Sun-Lin(4)
- Vural, Alaaddin(4)
- Akaryali, Enver(3)
- Dudas, Francis O.(3)
- Yi, Keewook(3)
- Yücel, Cem(3)
- Aslan, Zafer(2)
- Jeong, Youn-Joong(2)
- Siebel, Wolfgang(2)
- Temizel, İrfan(2)
- Abdioǧlu Yazar, Emel(1)
- Akdaǧ, Kemal(1)
- Akpinar, İbrahim(1)
- Akpınar, İbrahim(1)
- Arslan, M.(1)
- Aslan, Z.(1)
- Aydinçakir, Emre(1)
- Aydınçakır, Emre(1)
- Bektas, Osman(1)
- Bektaş, Osman(1)
- Bilici, Özgür(1)
- Celaleddin Bayraktar(1)
- Dokuz, Abdurrahman(1)
- Eker, Ç.Saydam.(1)
- Eker, Çiğdem Saydam(1)
- Gücer, Mehmet Ali(1)
- Güloğlu, Z. Samet(1)
- Hüseyin Enes Atay(1)
- Işık, Fatih(1)
- Kiliç, E. Demirkol(1)
- Kwon, Sanghoon(1)
- Levent Duygu(1)
- Mustafa Ataman(1)
- Sadıklar, M.Burhan(1)
- Saydam Eker, Çiğdem(1)
Yayınlar
- Yüksek Lisans TeziAçık Erişim2026Karayaşmak (Demirözü-Bayburt, KD Türkiye) ve yakın çevresinin hidrotermal alterasyon mineralojisi ve jeokimyası açısından incelenmesi
Mustafa Ataman
Bu çalışma Karayaşmak (Demirözü, Bayburt, KD Türkiye) ve yakın çevresinin değerli baz metal ve elementlerin aranmasına yönelik alterasyon mineralojisi ve kayaç jeokimyası verileri kullanılarak hidrotermal alterasyon ve kütle değişiminin hesaplanması amaçlanmıştır. Çalışma alanında en yaşlı birim Pulur metamorfitleridir. Temel kayaçları oluşturan ve Permo-Karbonifer öncesi yaşlı olarak kabul edilen bu litostratigrafik birim gnayslar, amfibolitler, şistler ve metakuvarsitleri içerir. Bunların üzerine uyumsuzlukla Liyas yaşlı Hamurkesen Formasyonunun volkano-tortul serisi gelmektedir. Hamurkesen Formasyonu kumlu kireçtaşı, kumtaşı, kiltaşı, çamurtaşı, tüf, tüfit, aglomera, volkanik breş ardalanmasından oluşmaktadır. Formasyonu Kuvaterner yaşlı alüvyonlardan örtmektedir. Kumtaşları grovak olarak, tüfler ise litik kristal tüf diye adlandırılmıştır. Tüfler orta-yüksek K’lu kalk-alkali özellikte olup SI, CIA ve AI değerleri hidrotermal alterasyonu desteklemekte ve orta derece ayrışmıştır. Tüflerde serizitik ayrışma, serizit-karbonat ayrışma, klorit-karbonat ayrışma ve kloritik-propilitik ayrışma belirlenmiştir. Tüflerin kütle değişim hesaplamalarında (Zn+Cu+Pb) değerleri çok fazla değişmezken, (FeO+MgO) ve (K2O+SiO2) değerlerinin genel olarak artması bunların farklı hidrotermal süreçlerle geliştiği ve hidrotermal sıvıların bu metallerce fakir olduğu anlaşılmıştır. Tüflerde isocon analizine göre genel olarak %37,06-41,62 kütle kaybı ve %20,14-48,56’lık bir kütle kazancı gerçekleşmiştir. Kütle artmasının sebebi Ca, Na, Fe, Mg ve Si elementlerinin artmasından kaynaklanmaktadır. Tüflerde hidrotermal alterasyon minerallerinin gelişiminde hidrotermal sıvılar önemli bir rol oynamıştır. Tüflerdeki hidrotermal alterasyon ürünlerinin muhtemelen epitermal evrede, asidik-hafif alkali ortam koşullarında, hidrotermal alterasyonu sonucu ve dolayısıyla farklı hidrotermal alterasyon koşulları geliştiği için farklı kütle değişimleri oluşmuştur.
- 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.
- Yüksek Lisans TeziAçık Erişim2023Yağmurdere (Gümüşhane, KD Türkiye) ve yakın çevresinin cevherleşme potansiyelinin jeokimyasal ve jeoistatistiksel olarak irdelenmesi
Celaleddin Bayraktar
Bu tez çalışmasında Yağmurdere (Gümüşhane, KD Türkiye) ve yakın çevresindeki değerli ve baz metal elementlerin aranmasına yönelik belirlenen sahalarda, sediman jeokimyası verileri kullanılarak jeoistatistiksel yöntemlerle hedef prospeksiyon alanlarının tespit edilmesi, toprak ve kayaç jeokimyası verileri yardımıyla anomali alanlarının daraltılması, sahanın element dağılım haritalarının oluşturulması ve tüm bu veriler dikkate alınarak uygun sondaj yerlerinin belirlenmesi amaçlanmıştır. Bu kapsamda 2014-2021 yılları arasında arazi çalışmaları gerçekleştirilerek sahanın jeolojik ve jeokimyasal özellikleri belirlenmiştir. Sahadaki cevherleşme/element zenginleşmelerinin belirlenmesine yönelik olarak 191 adet sediman, 869 adet toprak ve 379 adet kayaç örneği alınarak, analizleri Maden Tetkik ve Arama Genel Müdürlüğü (MTA) Maden Analizleri Teknolojisi Dairesi Başkanlığında Cu, Pb, Zn, Mo, As, Sb, Ag, Au, Co, Ni, Bi, V elementleri için gerçekleştirilmiştir. Elde edilen element konsantrasyonları değişik istatistiksel metotlarla değerlendirilmiş olup, her bir element için bölgesel ve yerel eşik değerler tespit edilmiştir. Ayrıca her bir element dikkate alınarak Ters Mesafe Ağırlıklandırma (TMA) metodu ile element dağılımı (anomali) haritaları oluşturulmuş ve bu haritalardan yararlanılarak MTA tarafından Doğu Karadeniz Metalik Maden Aramaları Projesi kapsamında 4 farklı lokasyonda 14 adet karotlu maden arama sondajı gerçekleştirilmiştir. Sondajlara ait karot örneklerinden yapılan XRD çalışmaları ile sahada gelişmiş serizitik-fillik alterasyon zonları tespit edilmiş, cevher mikroskobisi çalışmaları ile de pirit, rutil ve fahlerz gibi cevher minerallerinin zenginleştiği alanlar tespit edilmiştir. Tüm bulgular birlikte değerlendirildiğinde hedef bölgelerdeki jeokimyasal veriler kullanılarak elde edilen ve jeoistatistik metotlarla oluşturulan element dağılım haritalarındaki anomali bölgelerinin, inceleme alanındaki cevherleşme ile ilişkili olduğu bu tez çalışması kapsamında ortaya konulmuştur
- MakaleAçık Erişim2023Magmatic evolution of the Calc-alkaline Middle Jurassic igneous rocks in the eastern pontides, NE Turkey: insights from geochemistry, whole-rock Sr-Nd-Pb, in situ zircon Lu-Hf isotopes, and U-Pb geochronology
Aydınçakır, Emre; Yücel, Cem; Kaygusuz, Abdullah; Bilici, Özgür; Yi, Keewook; Jeong, Youn-Joong; Güloğlu, Z. Samet
The Eastern Pontides in NE Turkey hosts a very limited number of plutonic rocks from the Jurassic period. Here we submit new geochemical, Sr-Nd-Pb and zircon Lu-Hf isotope data, and zircon U-Pb ages for plutonic rocks in this region. Zircon U-Pb dating for the Alemdar and Işıkdere plutons yielded an age of 175–170 Ma (Middle Jurassic). The Alemdar and Işıkdere plutons have I-type, medium to high-K calc-alkaline series, and metaluminous to slightly peraluminous characteristics. On PM-normalized diagrams, the plutons are enriched in large-ion lithophile elements (LILEs) with pronounced depletion of high field strength elements (HFSEs, Ta, Nb, Ti). Chondrite-normalized plots for the plutons show variable enrichment in light rare earth elements (LREEs) with depletion of heavy rare earth elements (HREEs). The rocks of the Alemdar Pluton have homogeneous ISr values (0.70585 to 0.70673), low εNd(i) values (−3.9 to −1.6), pozitif εHf(i) values (+3.3 to +9.1), and Hf single-stage model ages (563–712 Ma), whereas those of Işıkdere have high ISr values (0.70666 to 0.70673), low εNd(i) values (−3.9 to −3.8), εHf(i) values (−3.1 to +1.1), and Hf single-stage model ages (791–969 Ma). These values imply that they have different sources. These results suggest that the magma of the Alemdar was formed by the partial melting of a relatively depleted lithospheric mantle wedge interaction of the OIB-like melts, while those of Işıkdere have derived from the partial melting of an enriched mantle metasomatized by slab-derived sediments and then modified by fractional crystallization and crustal contamination in crustal magma chambers. Considering the available data, we conclude that the studied plutons were related to extensional tectonic events during the Middle Jurassic in response to the roll-back of the Paleotethys oceanic slab in the final stage of oceanic closure. These rocks are an example of the formation of deep subduction products following Early Jurassic subduction.
- Yüksek Lisans TeziAçık Erişim2022Güneydere (Bayburt) Plütonu'nun petrografik ve jeokimyasal özellikleri
Zeynep Delimehmet
Doğu Pontid Orojenik Kuşağı (Doğu Sakarya Zonu), Anadolu Levhasının şekillenmesinde jeolojik olarak önemli bir rol oynayan Alp-Himalaya orojenezinin etkisi ile oluşmuş olup farklı türde magmatik kayaları içermesi bakımından önemli bir alan konumundadır. Özellikle Karbonifer yaşlı plütonlar, doğu Pontidlerin güney kesiminde, daha geniş mostralar halinde ve daha yaygın olarak gözlenmektedir. Bu çalışma, Bayburt'un (KD Türkiye) Güneydere Köyü ve çevresinde yer alan granitik kayaçlar üzerinde yeni petrografik ve tüm-kayaç jeokimyasal veriler sunmaktadır. Bununla birlikte, bu kayaçların oluşumunda önemli rol oynayan kaynak bölge, petrolojik süreçler ve jeodinamik ortam da tartışılmıştır. Yaklaşık 5 km2'lik bir alanı kapsayan Karbonifer yaşlı Güneydere Plütonu, çalışma alanında Jura öncesi temeli temsil etmekte ve uyumsuz olarak Erken-Orta Jura volkanoklastik ve volkanik kayaçlar ile Geç Jura-Erken Kretase kireçtaşları tarafından örtülmektedir. Güneydere Plütonu esas olarak granit/granit porfir ve aplit, daha az oranda ise granodiyorit ve kuvarslı monzonit türü kayaçlardan meydana gelmektedir. Kayaçlar yüksek SiO2 içeriklerine (%60.43-75.51) ve yüksek K'lu kalk-alkaliden şoşonitiğe kadar uzanan bir afiniteye sahip olup I-tipi bir kaynaktan itibaren türemiştir. Granitik kayaçlar matalümin-peralümün karakterli olup çarpışma sonrası volkanik yay granitoyidleri ile benzerlik göstermektedir. Ana ve iz element trendleri, kayaçların oluşumunda plajiyoklas, hornblend, biyotit, apatit ve Fe-Ti oksit mineral fraksiyonlaşmasının önemli rol oynadığını göstermektedir. Kayaçların gelişiminde başlıca fraksiyonel kristallenme, az oranda ise asimilasyon±magma karışımının rol oynadığı ortaya konmuştur. Zirkon doygunluk sıcaklıkları düşük ilksel magma sıcaklıklarını yansıtmaktadır. Elde edilen tüm veriler Karbonifer yaşlı Güneydere Plütonu'nun ana magmasının alt/orta kıtasal kabuk kayaçlarının kısmi ergime sonucu türediğini ve kıtasal magma odasında farklılaşarak yerleştiğini göstermektedir.
- Yüksek Lisans TeziAçık Erişim2022Gülaçar (Gümüşhane) ve civarındaki paleozoyik yaşlı plutonik kayaçların petrografik, jeokimyasal ve petrolojik özeliklerinin incelenmesi
Hüseyin Enes Atay
Bu çalışmada, Gülaçar (Gümüşhane) ve civarında yer alan Paleozoyik yaşlı plütonik kayaçların mineralojik-petrografik ve tüm kayaç jeokimyasal özellikleri ortaya konularak, kayaçların oluşum mekanizmaları ve kökenleri ortaya konulmaya çalışılmıştır. İnceleme alanının tabanında Erken Karbonifer yaşlı Kurtoğlu Metamorfitleri yer alır. Geç Karbonifer yaşlı Gümüşhane Plutonu Kurtoğlu Metamorfitleri'ni kesmiştir. Bu birimler üzerine uyumsuz olarak Erken-Orta Jura yaşlı Şenköy Formasyonu gelir. Bu formasyon Geç Jura-Erken Kretase yaşlı Berdiga Formasyonu tarafından uyumlu olarak üstlenir. Tüm bu birimler Eosen yaşlı Karadağ Granitoyidi tarafından kesilmiştir. İnceleme alanındaki en genç birimler Kuvaterner yaşlı alüvyonlardan oluşur. İncelenen Paleozoyik yaşlı plütonik kayaçlar inceleme alanında yaklaşık 50 km2'lik bir alanda yayılım gösterir. Başlıca granit ve kuvarslı monzonit bileşimli kayaçlardan oluşur. Bu kayaçlar orta-iri taneli olup, ortoklas, kuvars, plajiyoklas, biyotit, amfibol ve opak mineralleri içerirler. İncelenen Paleozoyik yaşlı plütonik kayaçlar genel olarak I-tipi, peralümin ve orta-yüksek-K karakterli olup, yüksek SiO2 içeriklerine (% 63-77) sahiptirler. Kayaçlar büyük iyon yarıçaplı litofil elementlerce (LILEs) zenginleşmişlerdir. Kondrite göre normalleştirilmiş nadir toprak element desenleri konkav şekilli (LaN/YbN= 5.08-14.76) olup, negatif Eu anomalisi (EuN/Eu*=0.32-0.75) gösterirler. Ana ve iz element değişimleri dikkate alındığında, kayaçların gelişiminde plajiyoklas, hornblend ve Fe-Ti oksit fraksiyonlaşmasının etkili olduğunu görülür. Zirkon ve apatitlerde yapılan hesaplamalarda, kayaçların kristallenme sıcaklıkları 750-936 °C arasında değişmektedir. Tüm bu özellikler, yüksek molar (CaO+FeOT+MgO+TiO2) ve düşük molar (Na2O+K2O) / (FeOT+MgO+TiO2), K2O/Na2O ve Mg# içerikleri, incelenen Paleozoyik yaşlı plütonik kayaçların metabazalt / metagrovak türü kaynak kayaçların kısmı ergimesi ile oluşmuş olabileceğini gösterir.
- 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.
- 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.
- MakaleYalnız künye2019U-Pb geochronology, bulk-rock geochemistry and petrology of Late Cretaceous syenitic plutons in the Gölköy (Ordu) area (NE Turkey): Implications for magma generation in a continental arc extension triggered by slab roll-back
Temizel, İrfan; Arslan, Mehmet; Yücel, Cem; Yazar, Emel Abdioğlu; Kaygusuz, Abdullah; Aslan, Zafer
Late Cretaceous felsic plutons in the Eastern Pontides orogenic belt of Turkey are found in varying ages, sizes and compositions. The Late Cretaceous syenitic bodies, namely Direkli and Yeniköy Tepe plutons in the Ordu area, intruded into the Late Cretaceous volcanics and volcanoclastics, and compositionally consist of syenite and minor quartz-syenite with mainly granular and rarely porphyric, poikilitic and perthitic textures. The studied plutons contain K-feldspar, plagioclase, quartz, clinopyroxene, biotite and minor hornblende, and Fe-Ti oxide, apatite, and zircon. Mineral thermobarometer estimations imply that the syenitic plutons were crystallized in P-T conditions representing mid to shallow crustal levels. Petrochemically, these syenitic plutons show I-type, metaluminous-peraluminous transitional (A/CNK = 0.85–1.04) and shoshonitic features. LA-ICP-MS U-Pb zircon dating on the syenitic plutons yielded weighted mean ages of 78.5–72 Ma. Primitive mantle-normalized trace element patterns of the studied plutons are characterized by negative anomalies of Ba, Sr, Nb, Ta and Ti, and enrichment in Rb, Th, K, Ce and La. The chondrite-normalized rare earth element (REE) plots of the studied plutons show moderately enriched concave-shaped patterns (La N /Lu N = 10.3–10.7 for the Direkli pluton; La N /Lu N = 6.8–11.7 for the Yeniköy Tepe pluton) with negative Eu anomalies. The plutons have 87 Sr/ 86 Sr ratios (0.705368–0.706954), 143 Nd/ 144 Nd ratios (0.512600–0.512672), 206 Pb/ 204 Pb ratios (19.29–19.52) and 207 Pb/ 204 Pb ratios (15.65–15.67). The geochemical data, as well as regional geology, suggest that the Late Cretaceous syenitic plutons have formed in an extensional continental arc setting triggered by slab roll-back. The parental magma of syenitic plutons was derived from melts of lower crustal materials (metabasalt/metaandesite) and lithospheric mantle component.
- MakaleAçık Erişim2018Mineral chemistry, whole-rock geochemistry and petrology of Eocene I-type shoshonitic plutons in the Gölköy area (Ordu, NE Turkey)
Temizel, Irfan; Abdioǧlu Yazar, Emel; Arslan, Mehmet; Kaygusuz, Abdullah; Aslan, Zafer
The Eocene intermediate to felsic plutons are widespread in varying sizes and compositions throughout the Eastern Pontides Orogenic Belt in NE Turkey. Of these, two monzonitic bodies (namely the Eriko Tepe and Göl Tepe Plutons) in the Gölköy (Ordu) area, extend nearly in the orientation of NWSE and E-W and were emplaced into the Upper Cretaceous and/or Eocene volcanic and sedimentary rocks. Petrographically, the studied monzonitic plutons are compositionally fine to medium grained monzonite, monzodiorite and subordinate quartz-monzonite. They consist of plagioclase (An35-67), K-feldspar (Or61-96), quartz, clinopyroxene (Wo28-49En35-51Fs10-25), biotite (Mg#: 0.53-0.73) ± hornblende (Mg#: 0.65-0.82), Fe-Ti oxide with monzonitic, poikilitic, perthitic, rare antirapakivi and graphic textures. Mineral thermobarometer estimations imply that the plutons were crystallized in P-T conditions of mid to shallow crustal levels. Petrochemically, these monzonitic plutons show post-collisional, I-type, metaluminous (A/CNK=0.76-0.93) and shoshonitic features. The wholerock major oxide and trace element variations suggest that fractionational crystallization played a significant role in the evolution of these monzonitic plutons. The primitive mantle-normalized trace element patterns of the studied plutons are similar to each other with enrichment in large ion lithophile elements, Th, Ce and negative Nb and Ti anomalies. Moreover, the chondrite-normalized rare earth element plots of the plutons show moderately enriched concave-shaped patterns (LaN/LuN=9.3-12.6) with negative Eu anomalies (EuN/Eu∗=0.69-0.84), all of which imply plagioclase and clinopyroxene ± hornblende fractionations during their evolution. The geochemical data suggest that the monzonitic plutons have evolved from parental magmas derived from the melts of enriched lithospheric mantle, in a post-collisional setting.
- MakaleYalnız künye2018Geochemistry of Çoruh River Bed Sediments in NE Turkey: Implications in Weathering-Sedimentary Cycle, Provenance, and Metal Pollution
Eker, Ç.Saydam.; Kiliç, E. Demirkol
This study defines the source area, sub-aerial weathering, and sedimentary cycle level, as well as heavy metal content and origin, of the Çoruh River bed sediments. The studied sediments are geochemically classified as litharenite based on the ratio of the major element contents. Relative to the Upper Continental Crust (UCC), trace elements Rb, Sr, Ba, Th, U, Zr, Hf, Y, Nb, and Pb are generally depleted; Co, Ni, Cu, Sc, and V are generally enriched; and Au is depleted in some places and enriched in other places. The rare earth element (REE) distributions of the samples exhibit a trend similar to that of the upper continental crust (UCC); however, low to moderate depletion occurs in the bed sediments in UCC. The analyzed samples exhibit low Chemical Index of Alteration (CIA) values, Plagioclase Index of Alteration (PIA) values (<50), CIA/WIP (Weathering Index ratios <1), and substantially high Index of Compositional Variability values (ICV) (>1). Thus, the samples are not chemically mature and are mainly derived from non-altered sources and were exposed the simple cycling history. REEs are depleted in the river bed sediments, unlike the world river average silt, world river average clay, and suspended sediment in world rivers. Minor enrichment of Zn, Sn, and Sc contents, low-to-moderate enrichment of Cu content, very severe enrichment of as content, and extremely severe enrichment of Ni content of the analyzed samples are observed. Consequently, stream bed sediments are derived from intermediate sources close to mid-continental crust rather than felsic sources Low-to-moderate degrees of chemical weathering of these sediments indicate increased tectonic activity, increased erosion, and rapid sedimentation in semiarid to arid conditions in the source regions over time. Thus, the sediments are chemically immature. These sediments are exposed to lithogenic and anthropogenic contamination.
- MakaleYalnız künye2017Formation of the Eğrikar (Gümüşhane) Fe–Cu skarn type mineralization in NE Turkey: U–Pb zircon age, lithogeochemistry, mineral chemistry, fluid inclusion, and O-H-C-S isotopic compositions
Sipahi, Ferkan; Akpınar, İbrahim; Eker, Çiğdem Saydam; Kaygusuz, Abdullah; Vural, Alaaddin; Yılmaz, Meltem
The Eğrikar Fe–Cu skarn type mineralization is located approximately 100 km NW of Gümüşhane in NE Turkey. Geochemical analyses of diorite, which is thought to cause skarn, indicate medium K calc-alkaline (1.3 to ~ 2.3 wt% K2O), metaluminous to peraluminous (A/CNK = 0.76 to 1.13) and resembles a continental arc granite. The age of U–Pb zircon obtained from diorite is 42.3 ± 1.0 Ma, which reflects the age of skarn metasomatism after intrusion into Late Cretaceous sandy carbonates. Skarn formation zones are recognized as endo- and exoskarn. The endoskarn zone mainly consists of pyroxene with hedenbergite (Di4.31–28.14Hd59.29–80.82Jo5.0–35.55) at prograde stage. Mn content of pyroxene increases a slight from endo to exoskarn. Pyroxene is replaced by epidote and hornblende at the retrograde stage. The exoskarn zone comprises garnet with andradite (Ad91-99Gr01–07) and grossular-andradite (Ad44-95Gr05–54), epidote and quartz as silicate minerals, and magnetite and hematite as ore minerals. Magnetite is the abundant ore mineral and is accompanied by chalcopyrite and minor pyrite at retrograde stage. On the basis of fluid inclusion values of minerals, the temperature range for hedenbergite in endo-exoskarn is 350 °C–425 °C, for epidote in exoskarn is 365 °C–376 °C, and for quartz in exoskarn 200 °C–380 °C. NaCl equivalent salinity for hedenbergite 6.88–10.73 wt% and for quartz is 3.9–15.38 wt. The δ18O values of hedenbergite is 4.1 to 4.7‰ and for garnet 3.4‰ at prograde stage, for epidote 7.9–9.2‰, for magnetite 1 to 4.4‰, for hematite − 2.9 to − 1.6‰ and for quartz range between 8.5‰ and 15.2‰. The δ18O value of epidote suggests that oxygen is a magmatic fluid whereas hedenbergite, garnet, quartz and magnetite show the mixing of magmatic and meteoric fluids. In addition, the C isotope values (− 3.2 to 2.8‰) of calcite and marble in Eğrikar Fe–Cu skarn reflect those of metamorphic, and skarns. Based on oxygen isotope data from mineral pairs, the retrograde skarn formation is characterized by epidote–magnetite assemblage formed at 255 °C–438 °C. Fluid oxygen isotope compositions of magnetite and epidote pairs of the exoskarn skarn zone indicate a mixing of magmatic and meteoric fluids with narrow δ18O values between 7.17‰ and 8.9‰. The δ34S values of the pyrites exhibit a narrow range of 3‰ and 4.4‰, thereby indicating that sulfur were probably leached from magmatic rocks. Based on the field and laboratory observation, mineral chemistries, fluid inclusion studies and isotope composition analysis, it is suggested that the Eğrikar Fe–Cu skarn mineralization occurs in a magmatic origin fluids being initially under reduced conditions, subsequently under oxidized conditions, and at shallow depth.
- MakaleYayıncıda açık erişim2016Organic geochemistry and element distribution in coals formed in eocene lagoon facies from the Eastern Black Sea Region,NE Turkey
Saydam Eker, Çiğdem; Akpinar, İbrahim; Sipahi, Ferkan
The amount and type,the inorganic element content,and the maturity of organic materials of Eocene coals,shaly coals,and coaly shales exposed in the Gümüşhane and Bayburt districts of the Eastern Black Sea Region of Turkey were investigated. The depositional environments and hydrocarbon potentials were also interpreted. The total organic carbon concentrations in the studied samples ranged from 0.50% to 63.08%. The samples from Özyurt,Kayadibi,and Tarhanas contained types II and III kerogen,and those from Sökmen and Manas contained type III kerogen. The samples contained Co,Cs,Ga,Hf,Th,U,Y,Mo,Be,Cd,Sb,and La,with average values similar to those of standard brown coals. The samples showed average contents of Co,Ga,Nb,Rb,V,Y,Cu,Pb,Zn,As,Be,and Se,similar to those of other Turkish coals. The sediment source of Eocene samples in the five areas was characterized by rocks with intermediate or mafic geochemical characteristics. The terrigenous/aquatic ratio of coal and shaly coal samples of the areas in question is >1. The sterane distribution was C29 > C28 > C27 and C29 > C27 > C28 for the Özyurt and Tarhanas areas,respectively. The average Tmax values for samples are between 424 °C and 460 °C. For samples Oz-1 and Ta-2,22S/(22S + 22R) homohopane (C32) ratios are 0.48 and 0.61,respectively; 20S/(20S + 20R) sterane (C29) ratios are 0.18 and 0.53,respectively; and Ts/(Ts + Tm) ratios are 0.015 and 0.64,respectively. The Pr/Ph ratios of the samples are >3. The studied samples have low sterane/hopane and high (C19+C20)/C23) ratios without anoxic biomarkers (17α(H)-28,30-bisnorhopane). Based on these data,the coals,shaly coals,and coaly shales were probably deposited under an oxic-suboxic mixture of marine and terrestrial environment conditions; these materials contain terrestrial organic matter and cannot generate hydrocarbon.
- MakaleYalnız künye2015Contamination assessment of heavy metals associated with an alteration area: Demirören Gumushane, NE Turkey
Vural, Alaaddin
Soil samples collected from Demirören Alteration area, Gümüshane NE Turkey were analyzed for heavy metals by using Inductively Coupled Plasma-Atomic Emission Spectrometry and Inductively Coupled Plasma-Mass Spectrometry and the contamination level of heavy metals was assessed on the basis of Geoaccumulation Index, Enrichment Factor, Pollution Index and Integrated Pollution Index. The results indicated that, in comparison with background value of upper crust, soil samples in Demirören alteration area have elevated levels of metal concentrations as a whole. High Geoaccumulation Indexes and Enrichment Factors for molybdenum, lead, selenium, bismuth, cadmium and copper in alteration area indicated that there is a considerable amount of especially molybdenum, lead and copper pollution, which mainly originate from alteration in the area.
- MakaleYalnız künye2014Geochemistry of dacitic volcanics in the Eastern Pontides (NE Turkey)
Sipahi, Ferkan; Sadıklar, M.Burhan
Dacitic rocks that crop out around the Zigana Mountain (Gümüşhane) in the eastern Pontide (NE Turkey), are mainly composed of quartz, plagioclase, sanidine, amphibole, muscovite, and biotite as the main minerals. Zircon and rutile are the accessory minerals. Pyrite, chalcopyrite, and covellite are the opaque components. On the basis of trace-element data, dacites have been classified as Dacite-I and Dacite-II. Dacite-I is tholeitic-transitional, whereas Dacite-II is transitional-calc-alkaline. The geochemical variation can be explained by the fractionation of the common mineral phases, such as plagioclase, hornblende, magnetite, and apatite. Dacites also show island-arc properties, with negative Nb, Sr, P, and Ti anomalies. The trace-element distrubitions of the dacitic rocks reflect the typical characteristics of rocks from the subduction-related tectonic setting, with enrichment of large-ion lithofile elements and light rare-earth element, but depletion in high-field-strength elements. The dacitic rocks are developed through plagioclase ± hornblende-controlled fractionation from the same parental magma that settled in two successive stages and are derived from an enriched source, probably by the mixing of slab-derived and lithospheric melts.
- MakaleAçık Erişim2014Trace/heavy metal accumulation in soil and in the shoots of acacia tree, Gümüşhane-Turkey
Vural, Alaaddin
In this study, heavy metal/trace element accumulation was investigated in soils along the road passing through Gümüshane city center and shoots of 1-2 years of acacia trees (Robinia pseudoacacia L.) grown in these soils. Heavy metal contents in soils and plants were analyzed by Enrichment Factor (EF), Geo-accumulation index (Igeo) parameters, and by Bio Accumulation Factor (BAF), respectively. According to geo-accumulation index (Igeo) data, it is seen that the soil was unpolluted in terms of Cr, Co, Cu, Rb, Sr; unpolluted to moderately polluted in terms of V, Ni and Zn; moderate to excessively polluted in terms of As, and moderate to excessively polluted in terms of Pb. According to EF parameters, on the other hand, it is observed that the soil was non to slightly enriched in terms of Cr, Co, Sr and Ba; non to moderately enriched in terms of Ni and Cu; slightly to significantly enriched in terms of Zn; significant to very highly enriched in terms of As and slightly to over excessively enriched in terms of Pb. Although trace/heavy metal contents of acacia shoots were usually within normal values for acacia, it was determined that Cu, Fe, Mo, Ni, Sr and Zn concentrations were within and/or above upper limits of normal values in certain sampling points.
- MakaleAçık Erişim2013The nature of transition from adakitic to non-adakitic magmatism in a slab window setting: A synthesis from the eastern Pontides, NE Turkey
Eyuboglu, Yener; Santosh, M.; Dudas, Francis O.; Akaryali, Enver; Chung, Sun-Lin; Akdaǧ, Kemal; Bektaş, Osman
The eastern Pontides orogenic belt provides a window into continental arc magmatism in the Alpine-Himalayan belt. The late Mesozoic-Cenozoic geodynamic evolution of this belt remains controversial. Here we focus on the nature of the transition from the adakitic to non-adakitic magmatism in the Kale area of Gumushane region in NE Turkey where this transition is best preserved. The adakitic lithologies comprise porphyries and hyaloclastites. The porphyries are represented by biotite-rich andesites, hornblende-rich andesite and dacite. The hayaloclastites represent the final stage of adakitic activity and they were generated by eruption/intrusion of adakitic andesitic magma into soft carbonate mud. The non-adakitic lithologies include basaltic-andesitic volcanic and associated pyroclastic rocks. Both rock groups are cutting by basaltic dikes representing the final stage of the Cenozoic magmatism in the study area. We report zircon U-Pb ages of 48.71 ± 0.74 Ma for the adakitic rocks, and 44.68 ± 0.84 Ma for the non-adakitic type, suggesting that there is no significant time gap during the transition from adakitic to non-adakitic magmatism. We evaluate the origin, magma processes and tectonic setting of the magmatism in the southern part of the eastern Pontides orogenic belt. Our results have important bearing on the late Mesozoic-Cenozoic geodynamic evolution of the eastern Mediterranean region.
- MakaleYalnız künye2013Assessment of heavy metal accumulation in the roadside soil and plants of Robinia pseudoacacia, in Gumushane, Northeastern Turkey; [Yol kenari{dotless}ndaki topraklarda ve Robinia pseudoacacia bitkilerindeki aǧi{dotless}r metal birikiminin deǧerlendirilmesi, Gümüşhane, kuzeydoǧu Türkiye]
Vural, Alaaddin
The concentrations of heavy elements were studied in the soils and plants of Robinia pseudoacacia, along a highway passing through Gümüşhane City Center, Turkey. The aim of this study is to understand heavy metal accumulation due to dense traffic load, industrialization, urbanization, and/or geological features of the region. The assessment of the heavy metal accumulation of the soils is based on the Geoaccumulation Index and Enrichment Factor, and that of plants, is based on the Bioaccumulation Factor. According to the Geoaccumulation Index, soil samples were uncontaminated for Cr, Co, Cu, Rb, and Sr elements, uncontaminated to moderately contaminated for V, Ni, Ba, and Zn, and moderately to heavily-heavy contaminated for As. The contamination of soil samples changes from moderate-heavy-extremely contaminated degree for Pb. According to the Enrichment Factor; soil samples show, no enrichment-moderately-severe enrichment for V. Considering the Zn element, enrichment is in minor to severe enrichment. On the other hand, element enrichment is severe to very severe enrichment for As and that of Pb is minor to an extremely severe enrichment level. The data revealed that the soil in the study area is significantly contaminated for Zn, As, and Pb. Also, concentration levels of Cu, Fe, Mo, Ni, Sr, and Zn in the shoots of Robinia pseudoacacia at some location were determined as above and/or exceeded the upper limit of the normal range.
- MakaleYalnız künye2013Petrogenesis and U-Pb zircon chronology of adakitic porphyries within the Kop ultramafic massif (Eastern Pontides Orogenic Belt, NE Turkey)
Eyuboglu, Yener; Dudas, Francis O.; Santosh, M.; Yi, Keewook; Kwon, Sanghoon; Akaryali, Enver
High-silica adakites intrude the Kop ultramafic massif in the eastern Pontide orogenic belt of NE Turkey. These dominantly dacitic to rhyodacitic plagioclase porphyries form clusters of small intrusions. U-Pb dating of zircons from two intrusions yields ages between 52 and 59 Ma. The best-constrained crystallization age is 55.83 +/- 0.04 Ma, indicating that these are the oldest adakitic rocks of the eastern Pontides. The rocks show geochemical signatures typical of adakites. The absence of systematic geochemical variation within the adakite suite indicates a subordinate role for fractional crystallization and binary mixing, and suggests that individual intrusions may represent separate, small batches of magma. Modeling of partial melting suggests that the degree of melting was 5-20%, that the residues after melting likely contained garnet, clinopyroxene, and rutile, and that plagioclase was either absent or totally consumed during partial melting. The most likely source compositions had large-ion lithophile elements >10 times, and heavy rare earth elements <10 times, chondritic concentrations. Modeled bulk distribution coefficients indicate that the adakites were generated as silicic magmas, and are not derived by fractional crystallization from basaltic or andesitic parental melts. Sr, Nd, and Pb isotopic data indicate at least three isotopically distinct sources, one of which is depleted mantle. The other components include upper crust (possibly a mixture of subducted sediment and Hercynian continental basement rocks) and a component that may include both lower crust and sublithospheric mantle. These adakites are unique among the late Cretaceous and Cenozoic igneous rocks of the eastern Pontides in having a large proportion of the depleted mantle component. The prominent role of the depleted mantle in their petrogenesis suggests that the adakites may be related to a slab window in a south-directed subduction zone. (C) 2012 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
- Yüksek Lisans TeziAçık Erişim2011Eski Gümüşhane yöresinin jeolojisi ve Şenköy formasyonu (Erken-Orta Jura) içerisindeki kumtaşlarının petrografik ve jeokimyasal incelemesi
Levent Duygu
Çalışma, Eski Gümüşhane yöresini içerisine alan Trabzon H42-b2 paftasının jeolojik incelemesi ve Erken-Orta Jura yaşlı Şenköy formasyonu içerisindeki kumtaşlarının petrografik ve jeokimyasal özellikleri belirlenmesinden oluşmaktadır. Şenköy formasyonu inceleme alanında taban seviyelerinde konglomera ve silisleşmiş ağaç seviyelerinden oluşmaktadır. Yörede Şenköy formasyonu'nun en baskın litolojisi kömür ara seviyeleri ve kumtaşlarıdır. Şenköy formasyonu içerisindeki bu kumtaşları Jura öncesinde yer almış olan kaynak alanlarının petrografisi ve jeokimyası üzerinde önemli bilgiler saklamaktadırlar. İncelenen kumtaşlarında çatıyı oluşturan bileşenler kuvars, feldspat ve kayaç parçalarıdır. İncelenen kumtaşlarındaki kayaç parçaları asidik ve bazik kökenli olmak üzere iki ana grupta toplanabilirler. Bu kayaç parçalarının hem Jura öncesi temelde bulunması gereken volkanik kayaçlar hem de Erken Jura'da bölgede etkin olan bazik yay volkanizmasının ürünleri olabileceği belirlenmiştir. İncelenen kumtaşlarında felsik bileşenlerin oranını temsil eden Th ve U gibi iz elementler ile, mafik bileşenlerin oranını temsil eden Sc, Cr gibi iz elementler geniş aralıklar sunmaktadırlar. Bu durum kayaçların kaynak alanlarında felsik kayaçların yanı sıra önemli oranlarda mafik kayaçlarında bulunduğunu işaret etmektedir. İncelenen kumtaşlarının tüm kayaç jeokimyası ada yayı, aktif kıtasal kenar ve pasif kıtasal kenar gibi birden çok alana düşmektedir. Çalışılan kumtaşları Erken Jura'da yay gerisi konumda oldukları dikkate alındığında, kırıntılı kayaçların hem aktif volkanik yaydan hem de kıtadan malzeme alabilecek havzalarda çökeldikleri belirgindir. Çalışma alanında, Şenköy formasyonu içerisindeki çökeller içerisinde herhangi bir denizel fosil bulgusunun olmayışı, kömür ve bitki kırıntıları içeren seviyelerin ve silisleşmiş ağaçların varlığı, yersel ve yanal devamlılığı olmayan konglomera ve kumtaşlarının varlığı, çökellerdeki ani fasiyes değişimleri, incelenen kumtaşlarındaki bileşenlerin çoğunlukla köşeli olması, çok uzun mesafe taşınmamış olması ve kumtaşlarındaki silis çimento, bu çökellerin karasal bir ortamda çökeldiğini göstermektedir.
