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Reliable dating is essential in order to put palaeoclimatological, palaeoenvironmental and archeological information from continental carbonates in the correct time frame. This study evaluates U/Th dating of travertines based on two case studies, i.e., in the Ballik (Denizli, SW Turkey) and Sutto (N Hungary) areas. Previous petrographic, mineralogical and elemental characterization of the travertines enabled sampling of, purely calcitic, micrite or spar dominant, zones that are non-, or solely weak, cathodoluminescent. Despite adapted sampling and detrital thorium corrections, U/Th ages of the Ballik and the Sato travertines are inconsistent with their stratigraphic position. Based on the observation of wavy extinction affecting micritic fabrics and ghost structures, the studied travertines behaved as an open system for uranium after deposition through recrystallisation. Their U/Th ages, consequently, can only be considered as minimum ages. The Ballik travertines precipitated earlier than 0.55-1.31 Ma ago, when late-stage cementation along fractures and in cavities took place, and form the oldest travertines deposited in the Denizli basin. The formation of the Sato travertine area started at the earliest around 2.5 Ma with precipitation of the Cukor travertine. With some short interruptions, active travertine formation in the area took place maximally until 120 ka. The decreasing ages of the Sutto travertines towards the Danube, prove the complex nature of travertines both during deposition as well as during diagenesis, which leads to anomalies with regard to the law of superposition. The diagenetic susceptibility of continental carbonate deposits poses problems in terms of accurate and precise dating. U/Th dating of the intrinsically heterogeneous fabrics of travertines and tufa, as presently applied, should be ceased. Travertines and tufa up to similar to 100 ka might be the exception due to the limited extent of recrystallisation. Sparite cements and veins can be dated more accurately but, even with multiple samples from the same study site and inclusion of coeval samples, give only minimum ages for the whole deposits. To better constrain the time frame of the whole bodies, results from independent dating methods and from the surrounding deposits are necessary. In addition, it is important to keep in mind that the open-system behavior of continental carbonates has implications for diagenetic, palaeoenvironmental and palaeoclimatological studies based on geochemical proxies. C1 [Claes, Hannes; Torok, Agnes; Soete, Jeroen; Mohammadi, Zahra; Vassilieva, Elvira; Hamaekers, Helen; Marques Erthal, Marcelle; Aratman, Cihan; Swennen, Rudy] Katholieke Univ Leuven, Dept Earth & Environm Sci, Geodynam & Geofluids Res Grp, BE-3001 Heverlee, Belgium. [Claes, Hannes] Rhein Westfal TH Aachen, Clay & Interface Mineral CIM, Bunsenstr 8, DE-52072 Aachen, Germany. [Torok, Agnes; Mindszenty, Andrea] Eotvos Lorand Univ, Inst Geog & Earth Sci, Dept Phys & Appl Geol, Pazmany P Setany 1-c, HU-1117 Budapest, Hungary. [Soete, Jeroen] Katholieke Univ Leuven, Dept Mat Engn, Nondestruct Testing Res Grp, BE-3001 Heverlee, Belgium. [Hamaekers, Helen] SCR Sibelco Nv, Dept Geol, De Zate 1, BE-2480 Dessel, Belgium. [Marques Erthal, Marcelle] Petrobras Res Ctr, Av Horacio de Macedo Cidade Univ 950, BR-21941915 Rio De Janeiro, RJ, Brazil. [Aratman, Cihan; Ozkul, Mehmet] Pamukkale Univ, Dept Geol Engn, Kinikli Campus, TR-20070 Denizli, Turkey. [Cheng, Hai; Edwards, R. Lawrence] Univ Minnesota, Dept Earth Sci, Minneapolis, MN 55455 USA. [Cheng, Hai] Xi An Jiao Tong Univ, Inst Global Environm Change, Xian 710049, Peoples R China. [Shen, Chuan-Chou] Natl Taiwan Univ, Dept Geosci, High Precis Mass Spectrometry & Environm Change L, Taipei 10617, Taiwan. [Shen, Chuan-Chou] Natl Taiwan Univ, Res Ctr Future Earth, Taipei 10617, Taiwan. [Shen, Chuan-Chou] Natl Taiwan Univ, Global Change Res Ctr, Taipei 10617, Taiwan. [Kele, Sandor] Hungarian Acad Sci, Inst Geol & Geochem Res, Res Ctr Astron & Earth Sci, Budaorsi Ut 45, HU-1112 Budapest, Hungary.

A stalagmite from Dim Cave in southern Turkey contains a climate record documenting rapid and significant changes in amounts of precipitation between similar to 132 ka and similar to 128 ka, during the penultimate glacial - interglacial transition. Some U-Th dates have been compromised by carbonate dissolution but rigorous selection and tuning to delta O-18 records from other speleothems has generated a robust age model. Growth rate was initially very slow but a rapid increase at similar to 129 ka was accompanied by strong negative trends in delta O-18 and delta C-13, a combination implying the onset of much wetter conditions. Isotopic values at similar to 129 ka suggest that groundwater recharge rates and biogenic activity in the soil zone exceeded those of the early Holocene. A significant isotopic enrichment event at similar to 128 ka, during which there was alternating aragonite and calcite deposition, documents a strong drying event with a duration of similar to 200 years. A concurrent decrease in Sr-87/Sr-86 ratios indicates increased groundwater residence times and the cumulative evidence suggests amounts of rainfall fell from well above to slightly below present-day levels. Similar delta O-18 enrichment events are present in coeval speleothem records from southwest France and the Northern Alps, and these, together with pollen evidence from Italy, Greece and the Iberian margin of drier conditions at this time, imply that a climate anomaly extended across the northern Mediterranean borderlands. The timing, duration and structure of this episode are consistent with marine evidence of strong North Atlantic cooling early in the last interglacial and there is a resemblance to the Holocene 8.2 ka event recorded globally in many proxy-climate archives. C1 [Rowe, P. J.; Wickens, L. B.; Marca, A. D.; Peckover, E.; Andrews, J. E.] Univ East Anglia, Sch Environm Sci, Norwich NR4 TJ, Norfolk, England. [Sahy, D.; Noble, S.; Millar, I. L.] British Geol Survey, NERC Isotope Geosci Lab, Geochronol & Tracers Facil, Nottingham NG12 5GG, England. [Ozkul, M.; Baykara, M. O.] Univ Pamukkale, Dept Geol, TR-20070 Denizli, Turkey.

This research forms the basis for the applicability of the Dunham (1962) classification of carbonated rock lithofacies to the analysis of the giant Ballik travertine architecture, while reconstructing lateral and vertical environmental changes. This study provides an analogue for spring-related deposits encountered offshore Brazil and Angola by linking macroscopically travertine lithofacies distribution to depositional environments. The analysis is based on rock-building constituents such as gastropods, charophytes, intraclasts, phytoclasts, coated grains, dendrites etc., forming micro-sedimentary fabrics with different structures such as packstone, grainstone, wackestone and boundstone, these latter closely associated with crust of dendrites and phytoherm of reeds and bryophytes. Our findings indicate that the Ballik travertine area consists of a "Lower" and an "Upper Domain" reflecting different depositional environments. More specifically, the "Lower Domain" consists from west to east of a laterally complex amalgamation of extended pool, marsh pool and flood plain environments that formed from a mixture of spring and ground waters. The extended pond environment characterised by a boundstone facies of stromatolites in the west evolves eastward into a marsh pool and flood plain. This is because CO2 degassing and water temperature decreased as the water depth of the Lower Domain reduced towards the east. The marsh pool environment includes packstone to grainstone lithofacies and abundant wackestone lithofacies made of phytoclasts, whose crusts exhibit pustular fabrics. Moreover, the flood plains along with the marsh pool consist dominantly of packstone to grainstone lithofacies with many gastropods and intraclasts, interfingered with wackestone lithofacies made of phytoclasts. Irregular clotted fabrics, along with coated grains with radial fibres, high lime mud content with bioturbation are also present. The "Upper Domain" displays a laterally less heterogeneous palaeoenvironmental distribution with flooded slope and flood plain deposits. The eastern part of the "Upper Domain" is characterized by a systematic alternation of these environments, with intercalations of wackstone lithofacies made of phytoclasts, packstone to grainstone lithofacies made of intraclasts and lime muds as well as coated grains. The flood plain has coated grains having peloidal nuclei and coatings of sparry laminations and clotted fabric of peloids representing intraclasts, whereas, the flooded slope possesses coated grains with coatings of dendrites and nuclei of peloids, boundstone of stromatolites which have flat-laminated and columnar-laminated fabrics indicating a laminar discharge away from the spring(s). Alluvial fan and palustrine deposits with abundant bryophytes and reeds frequently interfinger with marsh pool environment in the "Lower Domain", and with the flood plain and flooded slope environments in the "Upper Domain". The results illustrate well how environmental changes identified in the two different domains have induced heterogeneity in reservoir-based depositional architecture. C1 [Aratman, Cihan; Swennen, Rudy; Mohammadi, Zahra] Katholieke Univ Leuven, Geodynam & Geofluids Res Grp, Dept Earth & Environm Sci, Celestijnenlaan 200E, BE-3001 Leuven, Belgium. [Aratman, Cihan; Ozkul, Mehmet] Pamukkale Univ, Dept Geol Engn, Kinikli Campus, TR-20070 Denizli, Turkey. [Marques Erthal, Marcelle] Petrobras Res Ctr, Av Horacio de Macedo Cidade Univ 950, BR-21941915 Rio De Janeiro, RJ, Brazil. [Hollis, Cathy] Univ Manchester, Dept Earth & Environm Sci, Williamson Bldg 2-69,Oxford Rd, Manchester M13 9PL, Lancs, England. [Claes, Hannes] Rhein Westfal TH Aachen, Clay & Interface Mineral, Energy & Mineral Resources, 18 Bunsenstr 8, DE-52072 Aachen, Germany.

Travertine geobodies have been identified as potential reservoir analogues to carbonate build-ups in pre-salt hydrocarbon systems. To investigate travertine geobody deformation, faults were mapped in 35 travertine quarries that excavate the Ballik travertine, i.e. a c. 12.5 km(2) large travertine geobody that precipitated at the intersection of the NE margin of the Denizli Basin and neighbouring Baklan Graben (SW Turkey). This travertine precipitated from cooling carbonate-saturated thermal spring waters that resurfaced along the margin fracture/fault network and through Neogene unconsolidated underlying sediments. From the Denizli basin floor to the uplifted graben shoulders, fault orientation is dominantly WNW-ESE oriented with major basin faults showing a left-stepping trend. Along the upper Denizli margin, travertine is only deformed by extensional normal faults. Along the lower margin, travertine starts with a subhorizontal facies but evolves to a travertine facies formed by a sloping topography with a domal architecture. Paleostress inversion of fault-slip data reveals that an Early Pleistocene NNE-SSW extensional-transtensional phase initiated the WNW-ESE oriented, graben-facing normal fault network. In the Middle Pleistocene, the Ballik fault network was left-lateral strike-slip reactivated because it acted as a transfer zone between the NW-SE extending neighbouring Baklan Basin and NW-SE extension along NE-SW oriented margin faults of the DGHS. In this stress configuration, travertine precipitated along the SW margin fault of the Baklan Graben. After strike-slip reactivation, a Late Pleistocene-to-current NNE-SSW extensional stress regime reinstalled during which margin faults widened and active travertine precipitation moved to more central parts of the DGHS. As different tectonic regimes affect graben intersections, reservoir analogues can have a complex deformation history driven by fault reactivation and recurrent stress permutations. This study concludes that large travertine geobodies can form at graben intersections because of their susceptibility to enhanced fluid flow through the complex fault-fracture network. C1 [Van Noten, Koen] Royal Observ Belgium, Seismol Gravimetry, Ringlaan 3, B-1180 Brussels, Belgium. [Van Noten, Koen] Royal Belgian Inst Nat Sci, Geol Survey Belgium, Jennerstr 13, B-1000 Brussels, Belgium. [Topal, Savas; Baykara, M. Oruc; Ozkul, Mehmet; Aratman, Cihan] Pamukkale Univ, Dept Geol Engn, Kinikli Campus, TR-20070 Denizli, Turkey. [Claes, Hannes; Aratman, Cihan; Swennen, Rudy] Katholieke Univ Leuven, Dept Earth & Environm Sci, Geodynam & Geofluids Res Grp, Celestijnenlaan 200E, B-3001 Leuven, Belgium. [Claes, Hannes] Rhein Westfal TH Aachen, Clay & Interface Mineral Energy & Mineral Resourc, Bunsenstr 8, D-52072 Aachen, Germany.

Elemental data from travertines are a treasure of depositional and diagenetic information. However, correct interpretation requires proper data acquisition and treatment. This study shows how results from elemental analyses complement sedimentological and other geochemical, i.e. isotopic, data and thereby contribute to our understanding of fossil travertines. Multivariate statistical element analyses, after multiple travertine digestion methods, demonstrate the link between elements, their mineralogical phases, and ultimately their origin. This study reveals that carbonate-phase related elements in travertines (Sr, S, Ba, Mg and Na) originate dominantly from the fluid source rocks. In combination with the delta O-18 and delta C-13 signatures, they are thus key geochemical variables for comparison of different travertine geobodies. Geochemical data analysis (elemental concentrations and isotope signatures), as illustrated here for the Turkish Battik travertines, supports interpretation with regard to fluid source rock, distance from the vent and relative intensity of processes like evaporation and degassing. For fossil travertines, geochemical data can thus provide crucial insights for understanding the hydrologic system. In particular when information is restricted to borehole data, like in subsurface reservoirs, their application could be decisive. (C) 2019 Elsevier B.V. All rights reserved. C1 [Claes, Hannes; Soete, Jeroen; Dirix, Katrijn; Vassilieva, Elvira; Erthal, Marcelle Marques; Vandewijngaerde, Wim; Hamaekers, Helen; Swennen, Rudy] Katholieke Univ Leuven, Geodynam & Geofluids Res Grp, Dept Earth & Environm Sci, Celestijnenlaan 200E, B-3001 Leuven, Belgium. [Claes, Hannes] Rhein Westfal TH Aachen, CIM, Bunsenstr 8, D-52072 Aachen, Germany. [Huysmans, Marijke] Vrije Univ Brussel, Hydrol & Hydraul Engn, Pl Laan 2, B-1050 Brussels, Belgium. [Dirix, Katrijn] Flemish Inst Technol Res, VITO, Boeretang 200, B-2400 Mol, Belgium. [Erthal, Marcelle Marques] Petrobras Res Ctr, Av Horacio de Macedo Cidade Univ 950, BR-21941915 Rio De Janeiro, RJ, Brazil. [Hamaekers, Helen] SCR Sibelco Nv, Dept Geol, Zate 1, BE-2480 Dessel, Belgium. [Aratman, Cihan; Ozkul, Mehmet] Pamukkale Univ, Dept Geol Engn, Kinikh Campus, TR-20070 Denizli, Turkey.

The recent discoveries of deeply buried Cretaceous reservoir bodies in the Atlantic Ocean revealed that relationships between the distribution of spring carbonate deposits and faults are poorly understood. The well-exposed Quaternary deposits at Obruktepe (Denizli Basin, Turkey) provide an opportunity to reconstruct the three-dimensional sedimentary architecture of such a system. Integration of sedimentological, lithofacies and geochemical analyses reveals complexity in the lateral relationships between sedimentary environments, faults and geothermal spring carbonates. Five environmental systems are distinguished based on the lithofacies analysis: (i) vent; (ii) smooth slope; (iii) travertine-terrace; (iv) tufa-barrage; and (v) flood systems. Encrusting, baffling and settling sedimentary processes are reflected in data acquired at several scales, from lithofacies observations to the morphology and arrangement of geobodies, together with microfabrics and stable carbon and oxygen isotope data. Mean values of +4.9 parts per thousand delta C-13 and -8.74 parts per thousand delta O-18 Vienna PeeDee Belemnite reflect geothermal circulation of springwaters. The environmental distribution and lithofacies indicate a lateral continuum between travertine and tufa deposits within this hot spring system. This finding supports two depositional models in which water flow variation is the main control on both CaCO3 precipitation and the resulting formation of travertine and tufa. The proposed models address the factors responsible for the development of these complex mound-shaped carbonate spring deposits, and how they are related to fluid circulation at depth and in association with faults.

This study compares and contrasts the travertine depositional facies of two of the largest sites of travertine formation, located in very different geological contexts, i.e. the modern Mammoth Hot Spring (MHS) system in the active volcanic complex of Yellowstone National Park (USA) and the Pleistocene Cakmak quarry, a well-exposed example of the Ballik travertines in the extensional Denizli Basin (Turkey). New, 2D to 3D facies maps of both travertine systems, combined with microscopy, assist in proposing an integrated spring depositional model, based on the existing MHS facies model, understanding general controls on meter to kilometer scale travertine deposit architecture and its preservation, and provide quantitative estimates of facies spatial coverage and slope using GIS. The comparison resulted in the distinction of eight facies, grouped in five downstream facies zones from Vent to Distal Slope. Notwithstanding the different geological context of both travertine systems, observations show that several of the facies are strikingly comparable (draping Apron and Channel Facies, top-slope Pond Facies, crystalline Proximal Slope Facies and Distal Slope Facies), whereas other facies do not have a precise, exposed equivalent (Vent Facies, pavement Apron and Channel Facies, extended Pond facies and phyto Proximal Slope Facies). Combining observations of active springs at MHS with the Cakmak vertical travertine quarry exposures demonstrates that lateral and vertical facies transitions are a sensitive record of changes in the spring dynamics (flow intensity and paths) that become well-preserved in the geological record, and can be recognized as prograding, aggrading, retrograding trends or erosive surfaces, traceable over tens to hundreds of meters. Quantification of facies specific coverage at MHS shows that Proximal and Distal Slope Facies deposits cover as much as similar to 90% of the total mapped surface area. In addition, only similar to 7% of the surface is found to be marked by a waterfilm related to an active flowing spring. Slope statistics reveal that strong slope breaks can often be related to transgressive Apron and Channel Facies belts and that variable, but steep slopes (up to 40 degrees) are dominated by Proximal Slope Facies, in agreement with the Cakmak exposures. Integrating travertine facies and architecture of deposits formed in distinct geological contexts can improve the prediction of general spring facies distributions and controls in other, modern and ancient, subsurface travertine systems. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.

Petrographical and petrophysical properties of the Turkish Ballik-Belevi travertine shrubs demonstrate the necessity of reservoir oriented classifications for shrub-related lithotypes and associated pore types. The presented shrub-related lithotype classification incorporates morphology, size and fabric, which are linked to specific pore-types and sizes. The travertines show highly complex pore networks, as observed from Computed Tomography reconstructions, making them of interest for the development and optimization of pore characterization methodologies and techniques, following an upscaling approach. Porosity (3-15%) and permeability (0-505 mD) strongly vary for the Ballik-Belevi travertines. The highest porosities and permeabilities are measured for horizontal samples dominated by slightly dissolution enlarged intershrub and interdigit growth framework porosity, mostly found for dendritic shrubs. The presented shrub and pore-type classification can be applied to shrubs worldwide. Studying outcrop analogues of continental carbonates helps to better understand heterogeneities, lateral variability and properties of Pre-Salt Cretaceous continental carbonate reservoirs, offshore Brazil and Angola. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.

Carbonate spring deposits gained renewed interest as potential contributors to subsurface reservoirs and as continental archives of environmental changes. In contrast to their fabrics, petrophysical characteristics - and especially the importance of microporosity (< 1 mu m) - are less understood. This study presents the combination of advanced petrophysical and imaging techniques to investigate the pore network characteristics of three, common and widespread spring carbonate facies, as exposed in the Pleistocene Cakmak quarry (Denizli, Turkey): the extended Pond, the dipping crystalline Proximal Slope Facies and the draping Apron and Channel Facies deposits formed by encrustation of biological substrate. Integrating mercury injection capillary pressure, bulk and diffusion Nuclear Magnetic Resonance (NMR), NMR profiling and Brunauer-Emmett-Teller (BET) measurements with microscopy and micro-computer tomography (mu-CT), shows that NMR T-2 distributions systematically display a single group of micro-sized pore bodies, making up between 6 and 33% of the pore space (average NMR T-2 cut-off value: 62 ms). Micropore bodies are systematically located within cloudy crystal cores of granular and dendritic crystal textures in all facies. The investigated properties therefore do not reveal differences in micropore size or shape with respect to more or less biology-associated facies. The pore network of the travertine facies is distinctive in terms of (i) the percentage of microporosity, (ii) the connectivity of micropores with meso- to macropores, and (ii) the degree of heterogeneity at micro- and macroscale. Results show that an approach involving different NMR experiments provided the most complete view on the 3-D pore network especially when microporosity and connectivity are of interest.

Sonic velocities of Pleistocene travertines were measured under variable confining pressures. Combined with petrographical characteristics and petrophysical data, i.e. porosity, permeability and density, it was determined that travertine porosity, pore types and cementation control compressional-wave (V-p) and shear-wave velocity (V-s). At 40 MPa confining pressures, V-p ranges between 3695 and 6097 m/s and V-s between 2037 and 3140 m/s. Velocity variations in travertines are, as with all carbonates, primarily linked to sample heterogeneity, i.e. differences in fabric, texture and porosity. They thus not necessarily emanate from changes in mineralogy or composition. Body wave velocities have a positive correlation with sample density and an inverse correlation with porosity. The travertines, sampled in extensional settings with normal faulting activity, define a specific compressional-wave velocity (y-axis) versus porosity (x-axis) equation, i.e. (log(y) = -0.0048x + 3.7844) that differs from the V-p-porosity paths defined by marine carbonates. Acoustic wave velocities are higher for travertines than for marine carbonates. Travertine precipitates form rigid rock frames, often called framestone, with large primary pores. Marine carbonates on the other hand often consist of (cemented) transported sediments, resulting in a rock frame that permits slower wave propagation when compared to the continental limestones. Acoustic velocity variations are linked to variations in pore types. Mouldic pores (macropores) show faster wave propagation than expected from their total porosities. Microporosity, interlaminar and interpeloidal porosity result in slower acoustic velocities. Framework pores and micro-moulds are associated with lowered acoustic velocities, while vug porosity is found above, on and below the general velocity-porosity trend. Not only the pore type, but also pore shapes exert control on body wave velocities. Cuboid-and rod-like pore shapes increase the velocity, while plate-and blade-like pore shapes have a negative effect on the velocity. The study demonstrates how seismic sections in travertine systems can contain seismic reflections that are not caused by non-carbonate intercalations, but relate to geobody boundaries, in which the seismic expression is function of porosity, pore types and shapes. This study provides and relates petrophysical data, i.e. porosity, permeability and acoustic velocities of travertines and is of importance for the interpretation of seismic reflection data in subsurface continental carbonate reservoirs. (C) 2014 Elsevier Ltd. All rights reserved.

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 Ballk 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 Ballk travertine architecture that potentially can be used as an analogue for subsurface travertine reservoirs worldwide and illustrates the importance of the combined use of C-13 and Sr-87/Sr-86 signatures in the delineation of the CO2-origin of travertine precipitating waters.

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 Ballk 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 (

A sedimentological and geochemical study was performed on the travertines in the southern part of the Usak geothermal field, western Turkey, to assess the applicability of a fluvial tufa facies model in interpreting late Quaternary travertine deposits developed along the stream valleys that follow fault and fracture systems. Modern thermal (31 to 38 degrees C) springs are found on the floor of the valley between 480 m and 520 m above sea-level. The distribution and nature of travertine facies were determined from natural outcrops. Samples of the travertines and spring water were characterized using a range of geochemical and petrographic methods. Waterfall, slope and pool facies associations consist of various combinations of travertine facies and subordinate detrital facies. Waterfall and slope facies associations of the older deposits occur where the springs emerged onto a hillslope or topographic break. In contrast, the pool facies association developed in depressions or flat areas that were fed by thermal springs. The youngest generation (1.85 ka) precipitated at lower elevations than the older ones (147 to 153 ka). Stable carbon and oxygen isotope values of the Aksaz travertines range between +4.3 parts per thousand and +6.3 parts per thousand (Vienna Pee Dee Belemnite) and -12.6 parts per thousand and -7.2 parts per thousand (Vienna Pee Dee Belemnite), respectively. The high delta C-13 values suggest that the thermal waters were charged with isotopically heavy CO2 of deep origin. Based on palaeotemperature calculations, the temperatures of the palaeosprings are slightly higher (up to 44 degrees C) than the present equivalents, but sometimes the temperature is lower, probably due to mixing with the stream water. Although the thermal waters occasionally are impeded by fluvial activity, travertine precipitation occurs in the protected parts of the Aksaz Stream valley. This contribution highlights the applicability of the fluvial facies model for tufa for the interpretation of travertine deposits worldwide.

The NW-trending Denizli basin of the SW Turkey is one of the neotectonic grabens in the Aegean extensional province. It is bounded by normal faults on both southern and northern margins. The basin is filled by Neogene and Quaternary terrestrial deposits. Late Miocene-Late Pliocene aged Kolankaya formation crops out along the NW trending Karakova uplift in the Denizli basin. It is a typical fluviolacustrine succession that thickens and coarsens upward, comprising poorly consolidated sand, gravelly sand, siltstone and marl. Various soft-sediment deformation structures occur in the formation, especially in fine-to medium grained sands, silts and marls: load structures, flame structures, clastic dikes (sand and gravely-sand dike), disturbed layers, laminated convolute beds, slumps and synsedimentary faulting. The deformation mechanism and driving force for the soft-sediment deformation are related essentially to gravitational instability, dewatering, liquefaction-liquidization, and brittle deformation. Field data and the wide lateral extent of the structures as well as regional geological data show that most of the deformation is related to seismicity and the structures are interpreted as seismites. The existence of seismites in the Kolankaya Formation is evidence for continuing tectonic activity in the study area during the Neogene and is consistent with the occurrence of the paleoearthquakes of magnitude >5.

In the Denizli Basin (Turkey), located in the western Anatolian extensional province, travertine and tufa deposition has been an ongoing process for at least 600,000 years. Travertine bodies, which are 30 to 75 m thick and each covers areas of 1 to 34 km(2), are up to 1 km(3) in volume. Today, spring waters in this area have temperatures of 19 to 57 degrees C, are of the Ca-Mg-HCO3-SO4 type in the Pamukkale, Kelkaya and Pinarbasi areas and the Ca-Mg-SO4-HCO3 type at Cukurbag. Thermal waters along the northern margin of the basin are generally hotter than those in the east-southeast and south. The delta O-18 and delta D values of the spring waters indicate a meteoric origin. The average temperatures of the hydrothermal systems in the Denizli Basin appear to have decreased from Pleistocene to Holocene. Travertine, which formed from the hotter water, is more widespread than the tufa that formed in the cooler spring waters. Deposition of the travertine, which formed largely on slopes, in depressions, and along fissure ridges (mostly on northern basin margins), was controlled by the interplay between various intrinsic and extrinsic parameters. The travertines are formed largely of calcite with only minor amounts of aragonite in some of the vertically banded, crystalline crust, raft and pisoid travertines found in some of the northern sites. The aragonitic samples, rich in Sr, are typically found around the spring orifices and along the central axis of the fissure ridges. The stable isotope values of the travertine found in the northwest and southeast parts of the basin are different. The delta C-13 values of the northern travertine deposits are more positive (3.7 to 11.7 parts per thousand. VPBD) than those found in the south-southeast areas (-4 to 5.8 parts per thousand VPDB). In contrast, the travertine and tufa in the southeastern areas have higher delta O-18 values (-15.2 to 7.8 parts per thousand VPDB) than those of the northern areas (-16.6 to -4.8 parts per thousand VPDB). Available evidence indicates that spring activity and associated travertine precipitation in the Denizli Basin were controlled largely by tectonic activity rather than by climatic conditions. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

The field of polymers in concrete is consolidated in the construction industry. The future of polymers in concrete is governed by the synergic interaction between these materials, in order to contribute significantly towards a more sustainable construction. Concrete-polymer composites (C-PC) have excellent mechanical and durability properties. Appropriate combination of polymers and classical construction materials provides opportunities for innovative applications and systems. This paper highlights the innovations and new approaches presented at the 13th International Congress on Polymers in Concrete in Madeira, Portugal, 2010 and at the 7th Asian Symposium on Polymers in Concrete in Istanbul, Turkey, 2012. The new trends presented are related with the micro and nanostructure, properties, test methods and applications of concrete-polymer composites.

Fissure ridge travertines grown from geothermal springs of Denizli Basin, southwestern Turkey, are investigated through stratigraphic, structural, geochemical, and geochronological methods, with the aim of understanding the growth of these elongate mound-shaped structures. Two main types of travertine deposits are recognized: (1) bedded travertines, which grew as flowstone on sloping surfaces and form the bulk of fissure ridges, and (2) banded travertines, which grew as veins within the bedded travertine chiefly along its central feeding conduit. Stratigraphic and structural observations shed light on the bedded-banded travertine relationships, where the banded features grew through successive accretion phases, crosscutting the bedded travertine or forming sill-like structures. The bedded and banded travertines alternated their growth, as demonstrated by complicated crosscutting relationships and by the upward suture, in places, of banded travertine by bedded travertine that was, in turn, crosscut by younger banded travertine. The bedded travertine is often tilted away from the central axis of the fissure ridge, thus leaving more room for the central banded travertine to form. U-series ages confirm the bedded-banded travertine temporal relationships and show that the growth of the studied fissure ridges lasted up to several tens of thousands of years during Quaternary time. The banded travertine was deposited mainly during cold events, possibly in coincidence with seismic events that might have triggered the outflow of deep geothermal fluids. C and 0 stable isotope and rare earth element data indicate a shallow feeding circuit for the studied structures with a fluid component deriving from a deeper geothermal circuit. A crack-and-seal mechanism of fissure ridge growth is proposed, modulated by the interplay of local and regional influencing factors and mechanisms such as geothermal fluid discharge, paleoclimate, tectonics, and the progressive tilting of bedded travertine limbs over a soft substratum creating the necessary space for the central veins to grow.

A27 cm thick, loose tephra deposits has been observed within coarse-grained colluvium at Cardak area of Denizli on the northern apron of the Acigol graben in western Anatolia, Turkey. It is a biotite-rich tephra with mean grain-size of coarse silt. Chemically it is dacite and rhyolite with average of 66.35% SiO2 and 4.70% alcalia (Na2O + K2O) in bulk analyses. It was deposited a time between 5380 +/- 90 and 2395 +/- 65 yrs cal. BP, possibly between 4750 and 3385 yrs cal. BP according to C-14 dating of two palaeosol layers within the colluvium. This is only and the thickest Holocene air-fall tuff layer found in terrestrial sediments in this region so far, and according to present knowledge there is no young volcanic source for such a formation in western Turkey. Analyses and comparisons of the analytic results with those of various young volcanic rocks suggest that the Cardak tephra originated from a volcanic source in the Aegean Sea. Besides, its geochemical composition, formation time and significant thickness represent probably a separate late Holocene explosive eruption in the eastern Mediterranean, apart from the Santorini event. (C) 2011 Elsevier B.V. All rights reserved.

Macro-defect free (MDF) cement is a cement-polymer composite with superior flexural strength although produced by mixing cement with small amounts of polymer and water. Special production technique and the crosslinking occurred between cement and polymer are important factors for obtaining such high strengths. However, MDFs lose considerable strength when exposed to water. The objective of this study was to explore the effects of TiO2 addition on flexural strength and water sensitivity of MDF. In this study, MDF cements were produced by adding up to 4% TiO2 by weight of cement. Biaxial flexural test as well as Atomic Force Microscopy (AFM) and Fourier Transform Infrared Spectroscopy (FTIR) tests were conducted in order to investigate the effect of TiO2 addition. TiO2 addition improved the water resistance of MDF cements in some batches, especially with 2% addition possibly due to the C-PVA-O-Ti-O-C-PVA bond and this cross-linking mechanism together with C-PVA-O-Al-O-C-PVA bonds cause a more stable polymer network.

In this paper we present the first detailed geochemical study of the world-famous actively forming Pamukkale and Karahayit travertines (Denizli Basin, SW-Turkey) and associated thermal waters. Sampling was performed along downstream sections through different depositional environments (vent, artificial channel and lake, terrace-pools and cascades of proximal slope, marshy environment of distal slope). delta C-13(travertine) values show significant increase (from +6.1 parts per thousand to +11.7 parts per thousand PDB) with increasing distance from the spring orifice, whereas the delta O-18(travertine) values show only slight increase downstream (from -10.7 parts per thousand to -9.1 parts per thousand PDB). Mainly the CO2 outgassing caused the positive downstream shift (similar to 6 parts per thousand) in the delta C-13(travertine) values. The high delta C-13 values of Pamukkale travertines located closest to the spring orifice (not affected by secondary processes) suggest the contribution of CO2 liberated by thermometamorphic decarbonation besides magmatic sources. Based on the gradual downstream increase of the concentration of the conservative Na+, K+, Cl-, evaporation was estimated to be 2-5%, which coincides with the moderate effect of evaporation on the water isotope composition. Stable isotopic compositions of the Pamukkale thermal water springs show of meteoric origin, and indicate a Local Meteoric Water Line of Denizli Basin to be between the Global Meteoric Water Line (Craig, 1961) and Western Anatolian Meteoric Water Line (Simsek, 2003). Detailed evaluation of several major and trace element contents measured in the water and in the precipitated travertine along the Pamukkale MM section revealed which elements are precipitated in the carbonate or concentrated in the detrital minerals. Former studies on the Hungarian Egerszalok travertine (Kele et al., 2008a, b, 2009) had shown that the isotopic equilibrium is rarely maintained under natural conditions during calcite precipitation in the temperature range between 41 and 67 degrees C. In this paper, besides the detailed geochemical analyses along downstream sections, we present new evidences of non-equilibrium calcite-water fractionation in lower temperature range (13.3 to 51.3 degrees C). Our measurements and calculations on natural hot water travertine precipitations at Pamukkale and Egerszalok revealed that the delta O-18(travertine) is equal with the delta O-18(HCO3) at the orifice of the thermal springs, which means that practically there is no oxygen isotope fractionation between these two phases. High rate of CO2 degassing with rapid precipitation of carbonate could be responsible for this as it was theoretically supposed by O'Neil et al. (1969). Thus, for the determination of the deposition temperature of a fossil travertine deposit we propose to use the water-bicarbonate oxygen isotope equilibrium fractionation instead of the water-travertine fractionation, which can result 8-9 degrees C difference in the calculated values. Our study is the first detailed empirical proof of O'Neil's hypothesis on a natural carbonate depositing system. The presented observations can be used to identify more precisely the deposition temperature of fossil travertines during paleoclimate studies. (C) 2011 Elsevier B.V. All rights reserved.

Ignimbrites are associated with nearly most of the world's volcanoes and are defined as a deposit from pyroclastic density currents. They consist predominantly of pumiceous lapilli and blocks, and glass shards, which shows evidence of having been emplaced as a concentrated hot and dry particulate flow. These rocks are widely used as building stone especially in ancient buildings. Bitlis valley is covered by ignimbritic products, derived from Nemrut stratovolcano, one of the significant volcanic centers in Eastern Anatolia. The Bitlis ignimbrite is separated into lower level (LL), middle level (ML) and upper level (UL) according to color, welding degree and structural features. All three levels were used extensively in many parts of the Bitlis castle as masonry materials. Studies were carried out on mineralogical and geochemical composition and on physical and mechanical properties of the ignimbrites. In addition, a freeze-thaw cycle test was executed. There are no considerable differences in mineralogical composition among the levels of ignimbrite. All levels contain plagioclase, sanidine, pyroxene, and opaque mineral. In addition, anorthoclase and quartz are seen. In general, the LL of ignimbrite shows relic perlitic and eutaxitic texture, whereas eutaxitic and vesicular texture are commonly developed in the ML and UL, respectively. Lower, middle, and upper level ignimbrite samples display similar and limited compositional spread in terms of major oxide elements. They have trachyte composition. Building stones can be classified according to mineralogy, mechanical and physical properties and processing types. Mechanical and physical properties are very important with respect to stone quality/durability. The mechanical and physical properties of the ignimbrites are controlled by the welding degree. It was found that increasing welding degree from UL to LL correlates with increasing density, compressive strength and slake durability index and with decreasing porosity. The Bitlis ignimbrites have turned out as susceptible to freeze-thaw cycles.

The determination of the geological age of two stalagmites (designated as A and B) found in Kelolan cave (Denizli, Acpayam, Turkey) was investigated using an electron spin resonance (ESR) technique. The natural ESR spectra had the signals of Mn2+ in addition to the signal at g=2.0006. In the ESR spectra of the -irradiated samples, three additional signals appear at g=2.0030, g=20016 and g=1.9972. The radicals produced by irradiation in stalagmites were attributed to orthorhombic and isotropic CO[image omitted] ion radicals. The signal intensity of the CO[image omitted] was used as a dating signal. Stalagmites were irradiated with a 60Co gamma source and measured with an ESR spectrometer (X-band) to obtain the signal intensity vs. dose curve, and fitted with the sum of two single exponential saturation functions. Based on this model, accumulated geological dose (DE) values for dating are obtained by using an additive dose method. The DE values of A and B stalagmites for each section range from 15 +/- 1 to 83 +/- 4 and 25 +/- 1 to 100 +/- 6Gy, respectively. As the 238U, 232Th and 40K concentrations of the stalagmites are very low, the measured in situ value of the external gamma dose rate was used for dating calculations. Because some parts of the stalagmites show secondary calcite recrystallization in the pore spaces, the calculated age values of these parts do not agree with the model of stalagmite growth. Except these porous parts, the ESR ages of other sections between A.5-A.8 and B.3-B.6 range from 14 +/- 2 to 86 +/- 18 and 24 +/- 5 to 92 +/- 19kyr, respectively, which is consistent with the model of stalagmite growth.

The nesting activities of Loggerhead Turtles (Caretta caretta Stejneger, 1902) and anthropogenic factors affecting them were monitored over 7 years (2002-2008) on Dalaman-Sarigerme beach, one of the main nesting grounds in Turkey. Out of the 2620 nesting emergences recorded during the entire study period, only 645 (24.6%) resulted in successful nesting, giving an annual mean number of nests of 92. The collective number of eggs in these nests numbered 50239, with 40079 (79.8%) of them producing hatchlings. Out of the total number of eggs laid, 8128 (16.2%) resulted in dead embryos and 2032 (4.0%) in unfertilized eggs. The mean incubation period averaged 49 days (range 40-67 days) and the mean clutch size was 79.0 (range 18-150 eggs). Turtle nests were more concentrated on the undeveloped parts of the beach than on developed parts. In the other sections, few emergences occurred and either no or few nests were recorded. In Section 1, which contained hotels and water sports facilities, only a few non-nesting emergences were observed. Of the number of nests that were observed, 32% were laid in Section II, which contained recently built hotels, 60% were in Section III and 8% were in Section IV, the undeveloped portion containing beach rocks. There is very clear evidence that the Loggerhead Turtles are shifting their nesting sites to the undisturbed sites along the beach. The negative factors that seem to be affecting them include water sports, hotel lights and beach rocks. In order to protect sea turtles, there needs to be a better understanding of how effective beach protection can be established.

Remains of fossil hominins from temperate regions of the Old World are rare across both time and space, but such specimens are necessary for understanding basic issues in human evolution including linkages between their adaptations and early migration patterns. We report here the remarkable circumstances surrounding the discovery of the first fossil hominin calvaria from Turkey. The specimen was found in the Denizli province of western Turkey and recovered from within a solid block of travertine stone as it was being sawed into tile-sized slabs for the commercial natural stone building market. The new specimen fills an important geographical and temporal gap and displays several anatomical features that are shared with other Middle Pleistocene hominins from both Africa and Asia attributed to Homo erectus. It also preserves an unusual pathology on the endocranial surface of the frontal bone that is consistent with a diagnosis of Leptomeningitis tuberculosa (TB), and this evidence represents the most ancient example of this disease known for a fossil human. TB is exacerbated in dark-skinned peoples living in northern latitudes by a vitamin D deficiency because of reduced levels of ultraviolet radiation (UVR). Evidence for TB in the new specimen supports the thesis that reduced UVR was one of the many climatic variables presenting an adaptive challenge to ancient hominins during their migration into the temperate regions of Europe and Asia.

The Denizli Basin (southwestern Anatolia, Turkey) contains a record of environmental changes dating since the Early Miocene. Detailed facies analysis of the Neogene formations in this half-graben enables us to document successive depositional regimes and palaeogeographic settings. Sedimentation commenced in the Early Miocene with the deposition of alluvial-fan and fluvial facies (Kizilburun Formation). At this stage, alluvial fans sourced from elevated areas to the south prograded towards the basin centre. The Middle Miocene time saw the establishment of marginal lacustrine and wetland environments followed by the development of a shallow lake (Sazak Formation). The uppermost part of this unit consists of evaporitic saline lake and saline mudflat facies that grade upward into brackish lacustrine deposits of Late Miocene-Pliocene age (Kolankaya Formation). The lake became shallower at the end of the Pliocene time, as is indicated by expansion shoreface/foreshore facies. In the Early Quaternary, the Denizli Basin was transformed into a graben by the activation of ESE-trending normal faults. Alluvial fans were active at the basin margins, whereas a meandering river system occupied the basin central part. Oxygen isotope data from carbonates in the successive formations show an alternation of wetter climatic periods, when fresh water settings predominated, and very and periods, when the basin hosted brackish to hypersaline lakes. The Neogene sedimentation was controlled by an active, ESE-trending major normal fault along the basin's southern margin and by climatically induced lake-level changes. The deposition was more or less continuous from the Early Miocene to Late Pliocene time, with local unconformities developed only in the uppermost part of the basin-fill succession. The unconformable base of the overlying Quaternary deposits reflects the basin's transformation from a half-graben into a graben system. C1 [Alcicek, Huelya; Ozkul, Mehmet] Pamukkale Univ, Dept Geol Engn, TR-20070 Denizli, Turkey. [Varol, Baki] Ankara Univ, Dept Geol Engn, TR-06100 Ankara, Turkey.

The neotectonic development of western Anatolia was characterized by the formation of numerous graben-type basins, which have been well documented by general mapping, although the cause and timing of the Neogene regional tectonic extension remain controversial. Previous interpretations of the origin and evolution of these Neogene basins were based mainly on regional-scale tectonic inferences, rather than detailed basin-fill analysis. The present study of the terrestrial intramontane Cameli Basin in the western Taurides combines detailed facies analysis with biostratigraphic dating (mammalian and molluscan fossils) and documents three pulses of crustal extension that are reflected in changes in the palaeogeography and sedimentary architecture of the basin. Development of the,ameli graben commenced in the Vallesian time (Early Tortonian), and is marked by alluvial-fan, fluvial and lacustrine depositional systems, with freshwater molluscan fauna. A second pulse of tectonic extension occurred in the Late Ruscinian time (Early-Middle Pliocene), producing a new normal fault that split the basin longitudinally into two compartments. The lake environment expanded and deepened, coastal peat-forming mires developed and abundant mammal fauna appeared by the Early Villanian time (Middle Pliocene), with the lacustrine deposits onlapping the basin-margin and intrabasinal fault escarpments. The lacustrine environment subsequently shrank, as the progradation of axial river deltas and basin-margin fan deltas caused water shallowing and shoreline regression. A third pulse of extension occurred at the end of Villanian time (Late Pliocene), when the development of a new generation of normal faults further split the basin into still narrower half-graben compartments. The third pulse of rifting is estimated to have accounted for little more than 10% of the sub-basinal crustal extension, but caused the most striking changes in the basin palaeogeography and drainage pattern. The inward development of the successive normal faults indicated a high-rate crustal extension. This is the first regional case study of a terrestrial neotectonic graben employing detailed sedimentary facies analysis and mammal biostratigraphy and providing a time-stratigraphic framework for the rifting pulses in western Anatolia. (C) 2004 Elsevier B.V. All rights reserved. C1 Pamukkale Univ, Dept Geol Engn, TR-20070 Denizli, Turkey. Ankara Univ, Dept Geol Engn, TR-06100 Ankara, Turkey. Gebze Inst Technol, TR-41400 Kocaeli, Turkey.