-
2024
- 2023
-
2022
-
2021
-
2020
-
2019
-
2018
-
2017
-
2016
-
2015
-
2014
-
2013
-
2012
-
2011
-
2010
-
2009
-
2008
-
2007
-
2006
-
2005
-
2004
-
2003
-
2002
-
2001
-
2000
-
1999
-
1998
-
1997
-
1996
-
1995
-
1994
-
1993
-
1992
-
1991
-
1990
-
1989
-
1988
-
1987
-
1986
-
1985
-
1984
-
1983
-
1982
-
1981
-
1980
-
1979
-
1978
-
1977
-
1976
-
1975
-
1974
-
1973
-
1972
-
1971
-
1970
-
1969
-
1968
-
1966
-
1964
-
1963
-
1961
-
1959
-
1958
-
1955
-
1954
-
1953
-
1952
-
1951
-
1950
-
1949
-
1948
-
1947
Abstract: Karahıdır plutonic and subvolcanic rocks exposed to the northwest of Avanos (Nevşehir) are included inthe Central Anatolian Granitoids. Subvolcanic rocks presenting porphyritic texture with coarse K-feldspar crystalswere emplaced in the region by cutting in the medium-coarse grained plutonic rocks. These rocks, which havesimilar mineral content, contain orthoclase, plagioclase, quartz, amphibole and biotite minerals. According to theresults of mineral chemistry, plagioclases are in andesine-albite-anorthoclase (Ab57-98), biotites are in Fe biotite(annite-sideophyllite), and amphibole are in Mg-Fe hornblende (magnesiohastingsite-ferroparhasite) compositions. Hornblende and biotite compositions represent a subalkalinealkaline magma character. The geothermobarometricresults of the minerals indicated that the Karahıdır pluton and subvolcanic rocks crystallized under the 0.41-1.91kbar pressure (P) and 692-804 °C temperature (T) conditions.Geochemically, Karahıdır pluton and subvolcanic rocks have quartz syenite and dacite porphyry, andesite porphyryand trachyandesite porphyry compositions. They are characterized by high total alkali (K2O+Na2O) content, Feindex value, large ion lithophile (LIL: Rb, Sr, Ba, K) and rare earth (REE) element content and low abundances ofCo, Ni and Sc and a low CaO/Al2O3 ratio and low Mg# value. The rocks exhibit shoshonitic, alkali-calcic to alkaline,metaluminous to peraluminous and ferroan in composition. In the chondrite normalized REE diagram, samplesexhibit enrichment of light rare earth elements (LREE) with a pattern (La/Ybn=16.3329.80) and negative-Eu [(Eu/Eu*)n=0.390.,66] anomaly. The rocks are relative to the primary mantle, enriched in some large ion lithophile (LIL;Rb, K and Th) and rare earth elements (REE), while depleted in field strength elements (such as HFSE; Nb, Zr, andTi). The Karahıdır pluton and subvolcanic rocks show typical post-collisional aluminum A-type granite featuresbearing subduction component. Plutonic and subvolcanic rocks derived from the lithospheric and asthenosphericmantle, which contains an important continental crust component
Abstract: The majority of the pyroclastic flow deposits in the Central Anatolia Volcanic Province (CAVP) havealready been subjected to hydrothermal alteration. In this study, we aimed to identify the dominant alteration typeunder different conditions and reveal the physicochemical conditions and geological processes that influencedsecondary mineral formation. The Zelve ignimbrite represents one of the most hydrothermally altered pyroclasticflow units in the study area. Juvenile pumice fragments from the Zelve ignimbrite were reacted with alkaline solutionsunder controlled experimental conditions, and reaction products in the form of zeolites were identified. Experimentalstudies were carried out under autogenic pressure and using alkaline solution activity agents such as NaOH, KOH,and NaHCO3 at a temperature of 150 °C, considering the most effective hydrothermal conditions in the region. Thereaction products obtained in experimental studies were identified by X-ray diffraction (XRD) and characterized by scanning electron microscopy (SEM). As a result, zeolite minerals such as phillipsite (K- and Na-), analcime,mordenite, and chabazite were synthesized. We concluded that NaOH alkaline solution is an effective activity agentin the formation of zeolite minerals during hydrothermal alteration of a juvenile volcanic product. In addition,zeolite phases naturally crystallizing in the region (analcime, phillipsite, chabazite, mordenite, clinoptilolite, anderionite) mostly coincide with the reaction products from experimental studies. Major and trace element compositionsof reaction products exhibited distinct differences with respect to starting composition. Reaction products wereenriched in major oxides of Na2O, K2O and CaO, whereas they were depleted in trace element concentrations of Rb,Ba and P. This indicates elemental exchange occurred between the solution and starting material to form zeolites.
Abstract: This study discusses the results of ecological risk analysis of sediments taken from Kilitbahir Port,one of the most active ports along the Çanakkale Strait (Dardanelles). ICP-MS analyses of the collected samplesrevealed moderate enrichment in Mo, Cu, and Zn in relation to anthropogenic activities in the studied sediments.The compatibility of the geoaccumulation and enrichment factor data indicates that the pollution is anthropogenic.No significant toxic risk was detected, although Mo is the most enriched potentially toxic element. The ecologicalrisk determined in terms of Hg and Cd is likely to be related to oil and fuel leaks caused by marine vessels passingto/from the Kilitbahir port and road traffic moving over the study area.
Abstract: Magnesite occurrences in Turkey are generally formed as veins and stockworks in fractures and fissuresof sedimentary rocks and altered ultramafic rocks. Ophiolitic units and magnesite formations crop out in the CentralAnatolia part of the Anatolian Block within the İzmir-Ankara-Erzincan Suture Belt and around Yakacık village,located 15 km northwest of Ankara. The genetical investigation of the ore-forming fluid(s) was carried out using mineralogy and petrography, XRDcharacteristics, geochemical investigations and C-O isotope studies of ophiolitic units and magnesite formationsin this study. Magnesite mineralizations were observed in two different forms, as quartz magnesite veins and asvein-stockworks, within the serpentinites of the Kapaklı member, which consists of olistostromal layers containingserpentinite, gabbro, diabase, basalt, radiolarite, and limestones around Yakacık. The vein-type magnesites showcryptocrystalline and microcrystalline structures and are accompanied by quartz, chlorite, dolomite, and serpentineminerals. Quartz, serpentine, olivine, calcite, and dolomite were determined in stockwork-type magnesite. The clayminerals were chlorite, smectite, and kaolinite.In mineralogical and Raman spectroscopic studies, both the vein- and stockwork-type mineralizations,alterations from olivine to kammererite and kammererite minerals were detected. The values obtained from the resultsof the geochemical analysis indicate that magnesites are associated with ultramafic rocks. In order to determine theorigin of magnesites, δ13C (VPDB) and δ18O (VSMOW) stable isotope studies were carried out on magnesite andlimestone. The δ13C and δ18O values are -3.07 to 9.67 and 23.05 to 27.49 for magnesites and 0.20 to 3.74 and27.05 to 28.96 for limestones, respectively. The most important rocks that could be the main source for the C andO of magnesite formations are Jurassic limestones.In conclusion, the movement of surface waters towards the depths, the heating role of volcanism during theearly-middle Miocene, the decarbonation of limestones due to the warming of the deep-flowing fluids, and theincorporation of CO2, partly from a magmatic contribution, are the main formation mechanisms of magnesite formedin the fractures of serpentinized ultramafic rocks.
Abstract: Gallbladder stone disease is the most common disease with a high prevalence in many societies in theword. In the literature, the primary risk factors discussed for this disease have been evaluated as gaining and losingweight rapidly, obesity, age, gender, genetic factors, having given birth too many children, life style and medications.The aim of this investigation is to find out the chemical and physical properties of gallstones in patients living inthe province of Antalya, Turkey. For this purpose, the chemical and mineralogical properties of 1243 gallstonesamples from 69 patients were analyzed using X-ray diffractometer (XRD), scanning electron microscopy (SEM)and Fourier-transform infrared spectroscopy (FTIR) applications.In accordance with the outcome of SEM and FTIR analysis, cholesterol, calcium carbonate, calcium bilirubinate,calcium phosphate, carbonate apatite, and protein contents were observed. Cholesterol was detected in 95% of 69patients; with 44 samples obtained from female patients. X-Ray Diffractometer (XRD) analysis showed newberyite,struvite, and aragonite minerals were found in the composition of gallstones. Newberyite was present in 59% ofthe samples. The physical, chemical and mineralogical characteristics of these gallstones are very important for theunderstanding of gallstone formation. The results of the study are consistent with the 5F Rule (Female, Forty, Fatty,Fair, Fertile). The relationship between bilirubinate and the presence of bacteria was determined. The presence ofbarium acetate and aluminum silicate in gallstones revealed the relationship with environmental pollutants.