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*Güllü, Bahattin ( Aksaray, Yazar ), Central Anatolia is bounded by the Izmir Ankara Erzincan (IAE) Suture Zone dipping northward beneath the Pontides at the north and the Inner Tauride (IT) Suture Zone with NE-dipping Central part of Turkey with triangular shaped structure. The Paleozoic metamorphic rocks are formed the basement of the Central Anatolia and obducted by the remnant of Inner Tauride ophiolitic products. Both of the units injected by Late Cretaceous age of the felsic and mafic intrusive unit. The mafic products mainly composed of gabbroic rocks and formed the less exposure crystalline magmatic rocks in comparison to the felsic crystalline magmatic rocks. The gabbroic rocks have a wide range in the exposure and mainly exposed at the eastern and far eastern part of Central Anatolia. They are ranging from a few meters up to kilometer square in dimension. The largest outcrops mostly accumulated with felsic intrusion in Central Anatolia. Different geographical distribution, colour, texture and mineral chemistry led to evaluate different source and nature in the region. MORB normalized elemental pattern of most of the gabbroic rocks of the Central Anatolian are enriched with the LIL elements with respect to HFS elements. Whole rock, trace and rare earth element results reveal that most of these mafic rocks are almost reveal almost similar geochemical behavior and patterns. The Raman spectra of the ophiolitic, intrusive and alkaline gabbroic rocks pyroxene mainly composed of augite, augite-diopside and augite- hedenbergite in composition respectively. The Electron Probe Micro Analysis (EPMA) results reveal that the pyroxene of the ophiolitic gabbro, intrusive gabbro and alkaline gabbro may crystalized at 178, 77 and 80 km depth with 46, 20 and 19 kilo bar pressure. Although the mineralogical, whole rock geochemical compositions are not able to differentiate between these gabbro the crystallization conditions of the pyroxene may be used in the classification of the gabbro types in Central Anatolia.

Rare earth elements (REEs) generate characteristic absorption features in visible to shortwave infrared (VNIRSWIR) reflectance spectra. Neodymium (Nd) has among the most prominent absorption features of the REEs and thus represents a key pathfinder element for the REEs as a whole. Given that the world's largest REE deposits are associated with carbonatites, we present spectral, petrographic, and geochemical data from a predominantly carbonatitic suite of rocks that we use to assess the feasibility of imaging REE deposits using remote sensing. Samples were selected to cover a wide range of extents and styles of REE mineralization, and encompass calcio-, ferro-and magnesio-carbonatites. REE ores from the Bayan Obo (China) and Mountain Pass (United States) mines, as well as REE-rich alkaline rocks from the Motzfeldt and Ilímaussaq intrusions in Greenland, were also included in the sample suite. The depth and area of Nd absorption features in spectra collected under laboratory conditions correlate positively with the Nd content of whole-rock samples. The wavelength of Nd absorption features is predominantly independent of sample lithology and mineralogy. Correlations are most reliable for the two absorption features centered at ∼744 and ∼802 nm that can be observed in samples containing as little as ∼1,000 ppm Nd. By convolving laboratory spectra to the spectral response functions of a variety of remote sensing instruments we demonstrate that hyperspectral instruments with capabilities equivalent to the operational Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) and planned Environmental Mapping and Analysis Program (EnMAP) systems have the spectral resolutions necessary to detect Nd absorption features, especially in high-grade samples with economically relevant REE accumulations (Nd> 30,000 ppm). Adding synthetic noise to convolved spectra indicates that correlations between Nd absorption area and whole-rock Nd content only remain robust when spectra have signal-to-noise ratios in excess of ∼250:1. Although atmospheric interferences are modest across the wavelength intervals relevant for Nd detection, most REE-rich outcrops are too small to be detectable using satellite-based platforms with>30-m spatial resolutions. However, our results indicate that Nd absorption features should be identifiable in high-quality, airborne, hyperspectral datasets collected at meter-scale spatial resolutions. Future deployment of hyperspec-tral instruments on unmanned aerial vehicles could enable REE grade to be mapped at the centimeter scale across whole deposits. University of Cambridge Higher Education Innovation Funding (HEIF) Natural Environment Research Council (NERC)

We present the results of a hydrogeochemical survey of the Bagni di Lucca area, a thermal district in the Serchio Valley, one of the areas of highest seismic risk in Tuscany, Italy. The aim of the survey was to identify a suitable site to be monitored for geochemical precursors of earthquakes. Based on hydrogeological and geochemical features, the Bernabò spring emerged as a proper candidate site for the installation and testing of an automatic monitoring station equipped with specific sensors for the continuous measurement of selected physical-chemical parameters (temperature, pH, electrical conductivity, redox potential).

Determining basaltic magma sources is easier than felsic magma sources. However, crustal contamination and crystal fractionations cloak important nature and source characteristic of the basaltic magma. To expose this privacy, it is necessary to use different spectroscopic methods to interpret the depth and origins of the intraplate basalts. In this study, Quaternary basalts have a huge outcrop in the southern region of Turkey has benefited from mineral compositions and the chemistry to reveal the origins of these basalts plateau. The basaltic plateau occupies the east and the western parts of Amanus Mountain of southern Turkey. They erupted of very different volcano flats and spread along the plateau-shaped basaltic volcanic interplated with the basaltic volcanic ash in the region. The present studies use the mineral chemistry with the geochemical data to constrain the source and the chemical evolution of the continental intraplate magmas from the Amanus mountain basalts. Two main textural features were exhibited in the basaltic outcrops, an aphanitic texture and a massive texture. Olivine and pyroxenes represent the main mafic component of these basaltic volcanic eruptions. The Confocal Raman Spectroscopy (CRS) studies reveal that, olivines are mostly forsterite and pyroxenes are diopsite and enstatite in compositions. According to the results of the electron microprobe analysis (EPMA) olivines are rich in Mg contents with forsterite and pyroxenes are rich in Ti contents and are in enstatite composites. According to the results of whole rock geochemical analyzes, these basalts exhibit an alkaline nature changing towards the tholeiitic magma nature. Two volcanic phases were classified in the study area. The first phase lavas, characterized by relatively high Si, low Ti and trace-element contents, are consistent with partial melting of a largely peridotitic mantle source. The second phase lavas are more complicated and characterized by a source component depleted in Si and enriched in Ti, Fe, Ca, Mg and P. According to the trace and rare earth element analyzes, the basalts show enrichment of LIL elements and impoverishment of HFS elements during the crystallizations. The tectonic discrimination diagrams, show that the basalts plot on the transition zone from the island arc to the alkaline basalts. Continental crust contaminations with the fractional crystallizations acts as mask in alkaline nature intraplate basalts to plots on the transition zone of alkaline and tholeiitic character bases. © SGEM2018.

Newly discovered K-bentonite beds, interstratified with limestones/dolomitic limestones of the Upper Devonian-Lower Carboniferous Yllanll Formation, are exposed in the northwestern Black Sea region of Turkey, around Zonguldak and Bartln. K-bentonite samples collected from four different locations: the Gavurplnarl and Yllanll Burnu quarries from the Bartln area, the Çimşir Çukurlarl quarry from the Şapça area, and the Güdüllü and Gökgöl highway tunnel section near Zonguldak city were investigated using optical microscopy,X-ray diffraction and inductively coupled plasma mass spectrometry in order to reveal their mineralogical and geochemical characteristics and understand their origin and evolution. The K-bentonites occur at different levels in the Yllanll Formation as 2-40 cm-thick, greenish to yellowish beds cropping out several hundred metres along strike. Preliminary biostratigraphic data suggest that the protoliths of the Bartln (Gavurplnarl and Yllanll Burnu) and Güdüllü K-bentonites were deposited at around the boundary between the Frasnian and Famennian, whereas those in the Şapça and Gökgöl sections are slightly younger (Devonian-Carboniferous boundary interval). The lithofacies types of the host carbonate rocks suggest an 'epeiric' shallow carbonate platform environment. Illite and mixed-layer illite-smectite were the major clay minerals in the K-bentonites. The K-bentonites from the Bartln area display a high degree of illitization and consist mainly of illite indicating high-grade diagenesis, whereas illite-smectite-rich samples from the Şapca and Gökgöl tunnel locations reflect relatively lower diagenetic conditions. According to their geochemical compositions, two groups of K-bentonites were distinguished, one with alkali basalt (Bartln area and Güdüllü locations) and one with trachyte affinities (Gökgöl tunnel and Şapça locations). Geochemical fingerprinting of K-bentonites by trace and rare earth element (REE) data suggest that tephras with alkali basalt composition have been derived by a source formed in a 'continental back-arc' setting, whereas the source of K-bentonites with trachytic precursors is related to 'continental within-plate rifting'. An evaluation of the global Late Devonian and Devonian-Carboniferous volcanism suggests that the bentonite precursors may be related to late-Variscan magmatism in Laurussia. © 2016 by Walter de Gruyter Berlin/Boston.

K-bentonite (tephra) layers are exposed as thin beds within Late Devonian-Early Carboniferous carbonates of the Yilanlı formation at four different locations in northwestern, Turkey. Clays separated from K-bentonites in the Gavurpınarı, Yılanlı Burnu (Bartın) and Çimşir Çukurları (Şapça) quarries and the Güdüllü-Gökgöl highway tunnel section near Zonguldak were analyzed by X-ray diffraction, optical, scanning and high-resolution transmission electron microscopy and inductively coupled plasma-mass spectrometry. The clay mineralogy is dominated by illite and mixed-layer illite-smectite (I-Sm) along with subordinate amounts of kaolinite, dolomite, calcite, quartz, feldspar, and gypsum. Morphologically, platy shaped illite is the major clay mineral in the Gavurpınarı and Yılanlı Burnu sites, while sponge-like to platy shaped mixed-layer illite-smectites occur in the Şapca Çimşir Çukurları and Gökgöl sites. Illite Kübler index (KI, ?°2?) and polytype data indicate high-grade diagenesis for illite-bearing site, and low-grade diagenesis for I-Sm-bearing sites. Lattice d060 values (?) of illite and I-Sm reflect a dioctahedral composition, with relatively larger d060 values in the Yılanlı Burnu site, which is related to Mg incorporation into the octahedral layer from dolomitic limestone host-rocks Illites have relatively lower tetrahedral Al substitution and higher octahedral Fe and Mg substitutions compared to those of I-Sm. Illites with phengitic composition occur in the Gavurpınarı and Yılanlı Burnu sites, whereas muscovitic composition at Şapca Çimşir Çukurları site. Chondrite-normalized rare earth element patterns for the Gavurpınarı and Yılanlı Burnu sites exhibit similar trends, with relatively higher values when compared to trends for the Şapça Çimşir Çukurları sites. Oxygen (?18O) isotope values of illites and I-Sm range from 17.7 to 21.9‰ (V-SMOW), whereas hydrogen (?D) isotope values range widely from - 10.1 to - 69.9‰ (V-SMOW). The depleted values of ?18O for the Gavurpınarı site imply geologically sudden crystallization under higher temperature conditions. K/Ar ages of different size illite fractions indicate the presence of older detrital illites (2 µm) together with younger diagenetic fractions (0.5 µm) that correspond with an increase of 2M1 polytype in the coarser fraction. Illitization ages of K-bentonites in the Bartın area indicate an Early Permian event corresponding to the Variscan orogeny, whereas the illitization of K-bentonites in the Zonguldak area is Early Jurassic in age, related to the Cimmerian deformation in the region. © 2016 Elsevier B.V.

The objective of this study is to demonstrate how fault dynamics may naturally be placed in the context of incremental stress theory, rock textural evolution modeling and standard conservation laws. Casting the fault dynamics problem in this framework naturally introduces rock memory for failure, fluid pressure effects and the autonomous nature of fault evolution. Poroelasticity, nonlinear viscosity and gouge are combined in an incremental stress rheology approach to examine the effect of changes in particle size distribution on fluid pressure in fault zones. © 2003 Elsevier Science B.V. All rights reserved.

The Denizli Basin is a fault-bounded Neogene-Quaternary depression located in the Western Anatolian Extensional Province, Western Turkey. The basin is a unique geological site with abundant active and fossil (Quaternary) travertine and tufa deposits. Fluid inclusion microthermometry and isotopic analysis were applied to study the genesis of the Ballik fossil travertine deposits, located in the south-eastern part of the basin. Microthermometry on fluid inclusions indicates that the main travertine precipitating and cementing fluids are characterized by low salinity (

The Denizli Basin in the West Anatolian Extensional Province in western Turkey is well-known for its numerous travertine occurrences. A combined sedimentological, diagenetic and geochemical investigation is executed on the Ece and Faber travertines of the Ballık area, the largest travertine site in the Denizli Basin. The first aim of this study is the reconstruction of a three-dimensional geo-model in combination with a detailed sedimentological description from fabric to lithotype, lithofacies and geobody scale, with a focus on integrating pore-typing. The second aim involves the delineation of the CO2-origin of ancient travertine precipitating waters. Peloidal, phyto and dendritic lithotypes dominate the studied travertines and honeycomb and bacteriform shapes and encrusted bacterial or fungal filaments related to their fabrics suggest a microbial influence. The environment of travertine precipitation evolved from dominantly sub-aqueous, as represented by the sub-horizontal and biostromal reed travertine facies, to dominantly sub-aerial in a thin water film, resulting in the cascade, waterfall and biohermal reed travertine facies. A general progradation of the travertine mound is indicated by the occurrence of stacked waterfall travertines. This results in sigmoidal clinoforms inside a general mound boundary configuration. Strontium and oxygen-carbon isotope signatures of the travertines point to a mixing mechanism of palaeofluids with deeply originated, heavy carbon CO2 with lighter carbon CO2 of shallow origin. These deposits can thus be considered as endogenic travertines. Carbonates of the Lycian Nappes acted as main parent carbon source rocks. The relative contribution of the lighter carbon isotopes is most likely to have originated from organic matter or soil CO2. This study provides a unique three-dimensional insight into the Ballık travertine architecture that potentially can be used as an analogue for subsurface travertine reservoirs worldwide and illustrates the importance of the combined use of δ13C and 87Sr/86Sr signatures in the delineation of the CO2-origin of travertine precipitating waters. © 2015 The Authors. Sedimentology and 2015 International Association of Sedimentologists.

Rare earth elements (REEs) generate characteristic absorption features in visible to shortwave infrared (VNIRSWIR) reflectance spectra. Neodymium (Nd) has among the most prominent absorption features of the REEs and thus represents a key pathfinder element for the REEs as a whole. Given that the world's largest REE deposits are associated with carbonatites, we present spectral, petrographic, and geochemical data from a predominantly carbonatitic suite of rocks that we use to assess the feasibility of imaging REE deposits using remote sensing. Samples were selected to cover a wide range of extents and styles of REE mineralization, and encompass calcio-, ferro-and magnesio-carbonatites. REE ores from the Bayan Obo (China) and Mountain Pass (United States) mines, as well as REE-rich alkaline rocks from the Motzfeldt and Ilímaussaq intrusions in Greenland, were also included in the sample suite. The depth and area of Nd absorption features in spectra collected under laboratory conditions correlate positively with the Nd content of whole-rock samples. The wavelength of Nd absorption features is predominantly independent of sample lithology and mineralogy. Correlations are most reliable for the two absorption features centered at ∼744 and ∼802 nm that can be observed in samples containing as little as ∼1,000 ppm Nd. By convolving laboratory spectra to the spectral response functions of a variety of remote sensing instruments we demonstrate that hyperspectral instruments with capabilities equivalent to the operational Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) and planned Environmental Mapping and Analysis Program (EnMAP) systems have the spectral resolutions necessary to detect Nd absorption features, especially in high-grade samples with economically relevant REE accumulations (Nd> 30,000 ppm). Adding synthetic noise to convolved spectra indicates that correlations between Nd absorption area and whole-rock Nd content only remain robust when spectra have signal-to-noise ratios in excess of ∼250:1. Although atmospheric interferences are modest across the wavelength intervals relevant for Nd detection, most REE-rich outcrops are too small to be detectable using satellite-based platforms with>30-m spatial resolutions. However, our results indicate that Nd absorption features should be identifiable in high-quality, airborne, hyperspectral datasets collected at meter-scale spatial resolutions. Future deployment of hyperspec-tral instruments on unmanned aerial vehicles could enable REE grade to be mapped at the centimeter scale across whole deposits.