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Öğe Geochemical features of the Menteşe Formation dolostones (Rhaetian) in the Karacahisar-Kasımlar area (Isparta-Turkey)(SpringerLink, 2018-08) Dinç, Salih; Özkan, Ali MüjdatThe purpose of this study is to determine the geochemical characteristics of the Menteşe dolostones (Rhaetian) in the west Taurus Mountains, Turkey. The isotope characteristics of the Menteşe dolostones show a variation in the δ18O values of the dolomites between + 1.35 and − 2.72‰ (VPDB) and a variation in the δ13C values of the dolomites between + 1.6 and + 3.33‰ (VPDB). Most of the Menteşe dolostone samples have positive oxygen isotope values; others have weak negative isotope values, which indicate early diagenetic development. In addition, oxygen, carbon, and strontium isotopes and trace element analyses suggest that these dolostones were probably resulted from insignificant recrystallizaion process than chemically similar fluids. Furthermore, Mn/Sr values of the Menteşe dolostones indicate that there is no significant diagenetic alteration. The total REE contents of the Menteşe Formation dolostones display a strong positive correlation with Si, Al, Fe, K, Ti, Ba, Rb and negative correlation with Mg, hence REE content is associated with in the first degree titanium-bearing minerals (probably sphene, rutile, anatase), second degree phosphate (apatite), and barium and rubidium-bearing minerals (probably barite). Ce anomalies versus Nd concentrations of the Menteşe dolostone samples indicate that these dolostones are formed in an anoxic environment. In addition, the K/Rb ratios of the Menteşe dolostones are not exposed to any metamorphism and indicate some diagenetic alteration. Calculated temperature values using δ18O values of the Menteşe dolostones yield precipitation temperatures of 17 to 42 °C, and suggest burial depths of 67 to 900 m. Sources of magnesium for dolomitization of the Menteşe Formation carbonates were most likely fluids from seawater and/or diagenetic brines (slightly modified seawater). The Menteşe dolostones formed as early diagenetic (Rhaetian to Cenomanian) in shallow burial areas at lower temperatures than seawater and/or diagenetic brines (slightly modified seawater).Öğe Measuring the sediment thickness in urban areas using H/V spectral ratio method in Batman region, Southeast Turkey(SpringerLink, 2021-02-03) Dinç, Salih; Alpaslan, Nuray; Yılmaz, SalimIn this study, microtremor records measured with a 3-component seismometer in Batman city center, which was established on the plain, were evaluated for the geological structure of the region and soil forming units. The measurements obtained from the field survey were evaluated with the Geopsy program by using the horizontal/vertical spectral ratio (Nakamura 1989) and the geological condition of the area and soil dominant frequency were determined. Soil characteristics of Batman City, which is geologically located on a plain, was evaluated by finding the loose units in the site with the map consisting of shear wave velocities (VS) found by applying the T = Σ4Hi /Vsi formula of Kanai (1983), which was developed for the soft soil layer on the bedrock, to the dominant frequency values (F0) obtained from the microtremor measured and soil classes corresponding to these values; and depth (H) and shear wave velocities (VS) were found by applying Formula (6) and the soil classes corresponding to these values. The dominant frequency at the measurement points and the lithology of the soil forming units were evaluated together to create dominant frequency maps of the region, and the relationship between the geology of the region and obtained microtremor measurements was discussed.Öğe Geochemistry of the cretaceous-tertiary (K/T) transition clays in the Southeastern Turkey(Komitet Zrównoważonej Gospodarki Surowcami Mineralnymi PAN, 2024-04-17) Tetiker, SemaThe mineralogy and chemistry of Upper Cretaceous -Lower Paleocene claystone sediments from Mardin and Batman, southeastern Turkey, were analyzed. The main mineral paragenesis in the Upper Cretaceous member formed chlorite-smectite (C -S) and illite, while the Lower Paleocene member occurred of chlorite -vermiculite (C -V) and vermiculite minerals. The clays were silica -poor but indicated high values of Al, Fe, Mg, Cr, Ni, V, and Zr. Lower contents of the alkali elements (Na, Ca, Mg, K) of the clayey sediments suggests a relatively denser weathering of the source area. The mineralogical compositions, major element ratios, trace, and rare earth element (REE) contents of the sediments show that the Upper Cretaceous member consists of materials with a mainly felsic source lithology, while relatively contributions from basic sources are found in the Lower Paleocene unit. A comparison of the major and trace element contents of the phyllosilicate/clay minerals with the members revealed that the patterns of the clays were different from each other, although the enrichments/decreases varied depending on the origin (basement rocks or detrital) of the derived rocks, minerals, and elements. REE content of clays increased from detrital to phyllosilicate/clay minerals of chemical/diagenetic/neoformation origin during the Lower Paleocene. During the Cretaceous and Tertiary periods, local or regional geodynamic and diagenetic events largely governed the rock sedimentation processes and provenance variations amongst Germav Formation members.
