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In this study, it is aimed to investigate the amethyst formations in the village of Yukarıgöçek (Bigadiç–Balıkesir) and, geology and geochemistry of the associated Musalar Granite. The magmatic and volcanic activities in the Biga Peninsula (NW Anatolia), which are found in the Sakarya zone, are intense the Oligo–Miocene period. The basement rocks of the study area is Paleozoic aged Fazlıkonağı Formation. The units are tectonically overlain by an Cretaceous aged ophiolitic melange. All these units are cut by the Oligo–Miocene age Musalar granite. Petrographically, Musalar granite has medium and coarse grains, occasionally poikilitic texture and contains plagioclase, orthoclase, quartz, biotite, amphibole and opaque minerals. Geochemically, it is high–K, calc–alkaline character and I type granitic rocks. It is rich with large Ion Lithophile Element and light rare earth elements, and the value of (La/Lu)N ranges from 13–34. Tectonically, it shows the characteristics of the after collision volcanic arc granites. The magma of pluton is lithospheric mantle origin and has been affected by the continental crust. The amethysts located in around Yukarıgöçek village have a thickness of 4–5 cm diameter in the ophiolitic rocks and are seen as veins. The color of amethysts, the roots and teeth of which are clearly visible, is usually light purple or lilac. Geochemically amethysts contain very few FeO and MnO. In the liquid inclusion studies, the homogenization temperature values are between 231 °C and 278 °C and the average is 255 °C. It can be said that the salinity and liquid density values of the studied amethyst samples are low and they are formed by hydrothermal way. As a result, the amethysts of Yukarıgöçek village could been formed by the cutting of the ophiolitic melange of Musalar granite and the siliceous rich liquid phase comes in the existing cracks in the ophiolitic melange in the hydrothermal phase at 255 °C. [ABSTRACT FROM AUTHOR]

Late Cretaceous aged intrusions in the Eastern Pontides Orogenic Belt in NE Turkey are common in varying sizes and compositions. Of these, Bozat Pluton (Giresun) extends nearly in the orientation of NE-SW and was emplaced into the Upper Cretaceous volcanic and sedimentary rocks. Petrographically, the studied pluton is compositionally fine to medium grained monzogabbro. The rocks of the pluton consist of plagioclase (An53-88), orthoclase (Or59-74), quartz, clinopyroxene (Wo40-45En42-44Fs12-17), biotite (Mg#: 0.66-0.70), Fe-Ti oxide, apatite and zircon with generally monzonitic, poikilitic, rare perthitic textures. Petrochemically, the studied pluton shows I-type, metaluminous (A/CNK=0.76-0.93) and shoshonitic features. The major and trace element data suggest that fractionational crystallization ± assimilation has played a significant role in the evolution of the studied pluton. Primitive mantlenormalized trace element patterns of rocks samples from the pluton exhibit enrichment in large ion lithophile element, Th, Ce and negative Nb, Ta and Ti anomalies, all of which suggest subduction component in their petrogenesis. Moreover, chondrite-normalized rare earth element (REE) plots of rocks from the pluton show characteristic concaveshaped patterns with negative Eu anomalies, all of which imply significant K-feldspar ± plagioclase and clinopyroxene fractionations in evolution of the pluton. All obtained data suggest that the Late Cretaceous aged Bozat Pluton has formed in an extensional continental arc, and parental magma of the pluton evolved from mixing of lithospheric mantle and lower crust-derived melts, and evolved differently within crustal level. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the geochemical properties of surface and groundwater in Kütahya and Köprüören plains and to determine the trace element contents. Major ion and trace element analysis of surface and groundwater in both plain were performed. According to major ion analysis, the chemical facies of natural waters in the region are controlled by carbonate rocks. It is determined that some trace element concentrations exceed the limit values in drinking water standards. Particularly, arsenic (As) concentrations in both plains exceed the recommended limit value of 10 ppb for drinking water at ten different points. The concentration of lead (Pb) and antimony (Sb) at Köprüören creek, which is drained to Enne Dam in Köprüören plain, is above the threshold values. In addition to arsenic and antimony, the concentrations of iron (Fe), zinc (Zn) and manganese (Mn) were found to be high in the regions where the local industrial establishments were located or in the vicinity of the mine enterprises. [ABSTRACT FROM AUTHOR]

In this study, the effects of the thermal and mineral waters in Yoğunağaç-Karakoçan and Dedebeğ-Mazgirt on the surface waters along the direction of the Peri Stream were determined that the samples were taken in two different periods (May/September). The distributions of the studied ions and some complex ions at the mixture setting Peri Stream and thermal and mineral waters are shown to decrease of K, Al, Cu, Mn and increase of Cl, Mg, HCO3, Ca, Na, SO4, As, B, Ba, Fe, Sb and Sr in May, while increasing of Cl, Mg, HCO3, Ca, Na, B, Mn, Al and Sb, decreasing SO4, K, Pb, Fe and Sr in the Peri stream water in September. While increasing of ion diversity due to rain fall during in May. According to the calculated saturation indices, Peri, Ohi streams and thermal and mineralized waters are oversaturated with minerals containing Fe, such as goethite and hematite. High Fe concentrations in stream and thermal and mineral waters should be related to the dissolution of Fe-bearing minerals in volcanites, sedimentary rocks and metamorphites. Oversaturation of the waters with clay minerals such as illite and kaolinite is related with the dissolution of clay minerals occurred in fractures and faults related with the active tectonism in the study area. The Peri Stream water sample when mixed with thermal and mineral waters, is classified as low quality water in terms of its contents of Ca, Mg, Na, K, Cl, SO4, HCO3, Al, Co, Mn, P and Pb when assessed according to the averages of intra-continental water resources. [ABSTRACT FROM AUTHOR]

The Craters of Meke Lake and Acıgöl are located in the district of Konya Province border and 6 km southeast of Karapinar. Compared with petrographical signatures, craters formed during the final stage of volcanism that effective in Plio-Quaternary comprise basalt-andesite and andesitic rocks and are found around the Meke crater, whilst the andesite and trachyandesite lithologies have been observed in Acıgöl. Volcanics formed by the main mineralogical composition plagioclases (Meke An56-80; Acıgöl An46-68), pyroxene (Meke Wo37-51, Acıgöl Wo40-48), amphibole and biotite are observed as mafic components. In Meke volcanics, these mafic components are accompanied by olivines (Fo70-85). The major element oxides of the rocks outcropping in the region show values the values of 51.32-64.88% SiO2, 1.16-3.09 K2O%, 2.39-3.92% Na2O, MgO 1.2-3.39%, 14.24-17.85% Al2O3, 0.18-0.35% P2O5, 5.59- 9.46%CaO, 0.09 to 0.15%MnO and the 5.17 to 10.21%Fe2O3. The Harker-type variation diagrams suggested that more basic characters of major oxides are observed in the rocks cropping out around the Meke Lake. MORB-normalized trace element patterns reflect strongly LILE enrichment and slightly HFSE depletion. The petrographic and geochemical studies indicate that the volcanic rocks of Meke and Acıgöl are characterized by the continental arc setting and the calcalkaline to alkaline in nature. The petrographic, geochemical and geothermobarometric studies indicate that Acıgöl and Meke volcanics crystallized under respectively 1093-1107 °C-0.9-1 kb and 1133-1141 °C - 4.7-5.3 kb conditions. Meke and Acıgöl are characterized by the continental arc setting and the calc-alkaline in natüre. [ABSTRACT FROM AUTHOR]

The study aims to investigate geochemical properties, chemical weathering, sedimentary-cycle history and sediment provenance of the Ankara Stream Pleistoceneaged terrace deposit. The CIA, PIA and ICV values of the examined samples have been determined as 58.6, 58.7 and 1.58, respectively. The terrace deposits are exposed to the simple sedimentary cycling history, which indicates that geochemical compositions of sediments were controlled by the composition of source materials. The Al2O3/TiO2, La/Sc, Co/Th and Th/Sc ratios of the investigated samples range from 8-21, 2.52-4.4, 1.50-2.19 and 0.70-1.03, respectively. Thus, the deposits have negative Eu anomaly and high LREE/HREE ratios. Finally, likely low-to-moderate degrees of chemical weathering of these deposits show an increase tectonic activity and erosion in the studied area. Terrace deposits are derived from particle to intermediate or felsic-mafic sources and the deposits are chemically immature. [ABSTRACT FROM AUTHOR]

Late Cretaceous era is characterized by densely volcanic and granitic activities in the Eastern Pontides that is northeast part of the Sakarya Zone. In this era, thick pile of volcanic-volano-clastic rocks occurred during the activities of acidic and basic volcanic cycles. In this study, preliminary geochemical results of Late Cretaceous aged volcanic rocks that were cut by the plutons of Çaykara Intrusive Complex (Trabzon) are presented. Investigated rocks are cut by both Late Cretaceous and Eocene aged plutonic rocks; therefore, they are altered in some of the locations. They are yellowish- greenish-blackish in hand specimens and show aphanitic textures. They show microlithic porphphyric (including plagioclase porphyries) and intersertal textures under microscope. Euhedral and subhedral plagioclase crystals are anorthite 35 to 55 in composition. From the results of chemical analysis, the volcanic rocks are basalt, basaltic andesite, andesite and dacite in composition and their Mg# is ranging 30 to 65. In the primitive mantle normalized trace element diagram, the samples display negative Nb, P and Ti and positive Pb anomalies. In general, large ion lithophile (LIL) elements enriched compared to the high field strength (HFSE) elements in the same diagram. In chondrite normalized rare earth elements diagram, (La/Lu)N ratios are ranging from 4 to 15. While some samples are shown slightly negative Eu anomaly, some others show slightly positive anomaly. When the samples are plotted in tectonic discrimination diagrams, they fall in island arc volcanic fields. The main solidification processes involved in the evolution of the volcanics consist of fractional crystallization, crustal contamination ± magma mixing. In the light of all evidence supports the conclusion that the parental magma(s) of the Late Cretaceous volcanics probably derived from an enriched lithospheric mantle, previously metasomatized by subduction. [ABSTRACT FROM AUTHOR]

The Campanian volcanic rocks cropped out in the south of Akçaabat (Trabzon) region and surrounding area in the Eastern Pontides Orogenic Belt are basalt, basaltic andesite and andesite in composition and petrographycally consist of clinopyroxene (Wo39-46 En40-47 Fs8-20), plagioclase (An80-84), olivine and opaque minerals. 40Ar-39Ar step-heating dating method carried out on groundmass of volcanic rocks yielded 82.61±0.34 Ma (Upper Cretaceous, Campanian). The volcanic rocks have calc-alkaline affinity and primitive mantle (PM) normalized trace element patterns imply subduction fingerprints with enrichment in large ion lithophile elements (LILEs; Sr, K2O, Rb, Ba), Th and Ce, and depletion in Zr, Y, Nb, Ta and TiO2. Additionally, the chondrite-normalized rare earth element (REE) patterns show low to medium degree of enrichment (LaN/LuN=2-3.4). The role of fractional crystallization involved in parental magma generation of the volcanics is more effective than magma mixing and assimilation-fractional crystallization (AFC) processes. In the light of all data, the parental magma(s) of the Campanian volcanics were derived from a enriched lithospheric mantle source in spinel lerzolitic composition, previously enriched by subduction related fluids and it reached the final composition with the effect of fractional crystallization and minor amount of magma mixing. [ABSTRACT FROM AUTHOR]

Eocene volcanic rocks of the Mescitli (Torul/Gümüşhane) and surrounding area in the southern part of the Eastern Pontides are investigated as mineralogical, petrographical and geochemical. Mescitli volcanic rocks are basaltic andesite, basaltic trachy andesite, trachy andesite, andesite, dacite and rhyolite in composition, and consists of mainly plagioclase, alkali feldspar, quartz, hornblende, augite and biotite minerals. They show calc-alkaline affinities and have medium to high K contents. They are enriched in large ion lithophile and light rare earth elements, with pronounced depleted of high field strength elements. The chondrite-normalized REE patterns (LaN/LuN=5-14) show low to medium enrichment, indicating similar sources for the rock suite. The main solidification processes involved in the evolution of the volcanics consist of fractional crystallization with minor amounts of crustal contamination ± magma mixing. All evidence supports the conclusion that the parental magma of the rocks probably derived from an enriched subcontinental lithospheric mantle, previously metasomatized by fluids. [ABSTRACT FROM AUTHOR]

There are a lot of tectono-magmatic/stratigraphic units between Çelikhan-Sincik (Adıyaman). These units have intrusively and discordantly-tectonicaly contact relations. The units located at this region are represented by autochtonous and allochtonous units. The main subject of this study is petrography and petrology of allochtonous Şifrin plutonic rocks. There are different types of rocks, from acidic to basic in the Upper Cretaceous Şifrin plutonic rocks. Mafic microgranular enclaves is founded in the felsic plutonic rocks. According to land observations and geochemical-geochronological data, it is defined that Şifrin plutonic rocks shows the similar properties with Elazığ Magmatics and this rocks were placed allochtonously by composition regime. [ABSTRACT FROM AUTHOR]

The connection of Marmara Sea and Black Sea with global ocean and between themselves are established via the Çanakkale and Istanbul straits. Because of the shallow sill depths of these straits, these connections were interrupted in during the late glacial period (LGM). As a result of these important paleoceanographic events, Marmara and Black Seas experienced significant sedimentological, biological and chemical changes. Despite the high scientific interest and large number of previous studies, the timing and nature of the interruptions and reconnections of the two basins with each other and with the world ocean are still matters of debate. This debate has stemmed from mainly the following shortcomings of the previous studies: a) confinement of the study in one basin, b) selection of unsuitable core locations, and/or c) use of inadequate sampling resolution and proxies. To overcome these difficulties, we analyzed organic (Corg) and inorganic carbon (total carbonate:Tkarb) and determined sedimentation rates for the different climatic stages in four chronostratig-raphically well dated cores (two each) from the Black Sea and Sea of Marmara. As identified by the previous studies, three units are present in the Black Sea Cores GC-19 and SL-12 covering the period from the LGM to present. The uppermost unit is the Coccolith Unit that consists of microlaminated gray green mud containing alternations of coccolith-rich and clay-organic matter rich lamina. The unit started depositing when coccolit-hophore Emiliania huxleyi invaded the basin at 2720 a (calib.) BP and the present-day oceanographic conditions were established. The underlying unit is Sapropel Unit that consists of laminated dark gray mud with high (up to 21 wt %) Corg. The Lutit Unit deposited under lacustrine conditions that consists of gray clayey mud. The lake /marine transition is characterized by high total carbonate content (up to 80 wt %) in the Black Sea (C1 carbonate) and dated 9.3 ka (calib.) BP. The Sea of Marmara cores contain two lithostrati-graphic units deposited in the last 20 ka. The upper unit (Unit 1) is a green marine mud that includes a dark olive green Sapropel with more than 1.5 % Corg. The lower unit (Unit 2) is banded gray mud that was deposited under lacustrine conditions. The lacustrine / marine transition occurred 14.7 ka BP. Unit 2 includes a rhyodacitic ash layer that is defined as the Y-2 ash-layer of Santorini origin, dated 22 ka (calib.) BP. Sedimentological and geochemical (Corg and Tkarb) analysis, together with the changes in the sedimentation rates in the cores show that the Black Sea and Sea of Marmara were disconnected to each other during the LGM but connected during the post-glacial Heinrich 1 (H1, 17.9-16.5 ka BP), Red Clay Layer (RL; 16.2-14.8 ka BP) and Younger Dryas (YD, 12.9-11.9 ka BP) cold periods when large inputs of freshwater and sediment occurred to the Black Sea and Marmara basins by the west and northwest European rivers, leading to one-way connection between the two basins. In between the post-glacial cold periods during the early Holocene (11.9-9.3 ka BP) and Bølling-Allerød (14.8-12.9 ka BP), carbonate-rich C2 and C3 units, predominantly of calcite composition, were deposited with low sedimentation rates respectively. During these carbonate depositional periods relatively warm and dry conditions with low water levels prevailed in the Black Sea and the Sea of Marmara, and no connection existed between the two basins. Another carbonate depositional event, this time predominantly of aragonite composition, took place in the Sea of Marmara and the Black Sea as during the lake/marine transition. The carbonate beds are dated 14.5-12.9 ka BP in the Sea of Marmara and 8.6-7.6 ka BP in Black Sea (C1); the event in the Sea of Marmara partly overlapping with the Bolling/Allerod (B/A). The carbonate deposition in both the basins took place as a result of mixing of lacustrine and marine waters leading to carbonate overstaturation. Sapropels were deposited in the Black Sea and in the Sea of Marmara Sea during 11.5-7.0 and 7.8-2.7 ka BP, respectively, when the Mediterranean waters poured sequentially into the lacustrine Sea of Marmara and Black Sea. Arrival of marine waters pushed up the nutrient rich deep waters up into the photic zone, thereby initiating high primary productivity and lead to water stratification, preconditioning the basins for the sapropel formation. The sapropel de-position was interrupted in the Sea of Marmara during YD and 8.2 ka BP cold periods as a result of increased deep water ventilation. [ABSTRACT FROM AUTHOR]

The Afyon-Bolkardağ Zone is one of the metamorphic belts, along with the Tavşanlı Zone, Menderes Massif and Lycian Nappes in western Anatolia, eastern Mediterranea. The study area included by thiz zone is located in the north of Ilgın (Konya-Turkey). Two main metamorphic groups and cover series unconformably overlaid each other from Ilgın of Konya province are reported in this study. From bottom to top, these are: Paleozoic metasedimentary group, Mesozoic metasedimantary and metavolcanic group, Neogene covers andQuaternary alluvium. The Paleozoic group is 1000m in thickness observed particularly in the west andmiddle part of the study area. This group is derived from the metamorphics of conglomerate, sandstone,siltstone, claystone, limestone and quartzite. Metaconglomerates consist of chert, shale, quartz and green schist fragments in clayey-sandy matrix. Metasandstones are grayish color, grain-supported,well-consolidated and carbonate cemented and bedding is from fine to medium. Phyllites are made up of mainly thin mica flakes and rarely fine-grained quartz and feldspar. Metacherts are thin-bedded, gray in color. Metacarbonates include elongated, flatted calcites, muscovite, chlorite, tourmaline and quartz. Metaconglomerates, at the base of Mesozoic group, purple-pinkish in color pass gradually laterally and vertically into metasandstones. Metasandstones are grayish-reddish-greenish color, mostly 5-30 cm and rarely 10 m in thickness. Metacarbonates are generally dolomitic limestoneand dolomite and gray, white and yellow in color. They are in upper levels of Mesozoic group. In this study, we stated that rhyolitic metavolcanics are different from others formerly cited in Ilgın (Konya). These rocks are light-dark gray and green colors. These are mostly metalavas and metatuffs unmapped in scale and thin bedded within schists. The black white alteration surfaces are widespread in the rocks considered lava origin. The foliation is marked in the passing into the schists and muscovites are wieved along foliation plains. The Paleozoic metasandstone and schist samples have high content of SiO2. Na2O values of Paleozoic samples vary from zero to 2.15 % and a higher value of K2O (5.8 %) is found in some samples. The valuesof high Rb and low Sr in some samples are significant. Schists have 64.2-81.33% SiO2. These values suggest that the Paleozoic group is felsic lithologies and acidic in character. Ba values are in the range of 6-485 ppm. On the other hand, some samples have high Zr values (486 ppm). The high contents of Rb may have resulted from the presence of muscovite in these rocks. Na2O and K2O values are very low whereas Sr values are high in dolomitic metacarbonates. Magma composition changes due to mineral fractionations. K2O, CaO, MgO, Fe2O3 and TiO2 show negative correlations with increasing SiO2 whereas Na2O shows positive correlation. As the SiO2 content increases, the Sr, Ba, Co, Th, Scand Hf contents decrease and the Rb content increases. However, Cs shows variation. Linear correlations can be explained by fractional crystallizations whereas such unlinear trends as negative and/or positive correlations can be explained by partial alterations and magma mixing in major and trace element diagram. … [ABSTRACT FROM AUTHOR]

In the north of Pasinler (Erzurum), Upper Miocene-Pliocene volcanic rocks crop out. These volcanites are composed of basaltic andesite, andesite, dacite, rhyolite lavas and rhyolitic pyroclastics. The rocks show porphyritic, microlitic porphyritic, hyalo-microlitic porphyritic, vitrophyric, glomeroporphyritic, pilotaxitic and hyalopilitic textures. The investigated volcanites contain plagioclase (An29-80), olivine (Fo65-82), clinopyroxene (augite), orthopyroxene (enstatite), amphibole (Mg#: 0.57-0.71), biotite (phlogopite: 0.44-0.47, annite: 0.33-0.37), sanidine, quartz and opaque mineral (titano-magnetite and ilmenite). The volcanic rocks are calc-alkaline in character and have medium to high-K contents. Major oxide and trace element variations point out open-system magmatic differentiation in the evolution of rocks. Geochemical data indicate an important role of fractionation of phenocryst phases in the rocks during differentiation process. However, it is considered that assimilation±magma mixing might have accompanied to the process. High LILE (K, Rb, Ba, Th) and relatively low HFSE (Nb, Ta, Hf, Zr) contents of the rocks indicate that these rocks derived from parental magmas carrying subduction signature. [ABSTRACT FROM AUTHOR]

In the north of Pasinler (Erzurum), Upper Miocene-Pliocene volcanic rocks crop out. These volcanites are composed of basaltic andesite, andesite, dacite, rhyolite lavas and rhyolitic pyroclastics. The rocks show porphyritic, microlitic porphyritic, hyalo-microlitic porphyritic, vitrophyric, glomeroporphyritic, pilotaxitic and hyalopilitic textures. The investigated volcanites contain plagioclase (An29-80), olivine (Fo65-82), clinopyroxene (augite), orthopyroxene (enstatite), amphibole (Mg#: 0.57-0.71), biotite (phlogopite: 0.44-0.47, annite: 0.33-0.37), sanidine, quartz and opaque mineral (titano-magnetite and ilmenite). The volcanic rocks are calc-alkaline in character and have medium to high-K contents. Major oxide and trace element variations point out open-system magmatic differentiation in the evolution of rocks. Geochemical data indicate an important role of fractionation of phenocryst phases in the rocks during differentiation process. However, it is considered that assimilation±magma mixing might have accompanied to the process. High LILE (K, Rb, Ba, Th) and relatively low HFSE (Nb, Ta, Hf, Zr) contents of the rocks indicate that these rocks derived from parental magmas carrying subduction signature. [ABSTRACT FROM AUTHOR]