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Akihiro Kano - One of the best experts on this subject based on the ideXlab platform.
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Intra-annual perturbations of stable isotopes in Tufas: Effects of hydrological processes
Geochimica et Cosmochimica Acta, 2009Co-Authors: Masako Hori, T. Kawai, J. Matsuoka, Akihiro KanoAbstract:Abstract Tufas, which are freshwater carbonates, are potential archives of terrestrial paleoclimate. Time series of stable isotopic compositions commonly show regular seasonal patterns controlled by temperature-dependent processes, and some perturbation intrinsic to the locality. We examined three Tufa-depositing sites in southwestern Japan with similar temperate climates, to understand the origin of local characteristics in the isotopic records. Seasonal change in the oxygen isotope is principally reflected by temperature-dependent fractionation between water and calcite but was perturbed after heavy rainfalls overwhelming the stability of the δ18O value of the groundwater at one site. Isotopic mass balance indicates an undersaturated and relatively small aquifer at this locality. Water δ18O values at the other two sites were stable, reflecting a regular seasonal change in the δ18O value of Tufa. Perturbation of the δ13C values in Tufa is largely due to CO2 degassing from the stream, which significantly increases the δ13C values of dissolved inorganic carbon (DIC). At a site with remarkably high pCO2 in springwater and a sensitive response of flow rate to rainfall, the amount of CO2 degassing changed distinctly with flow rate. In contrast, the other two sites having low pCO2 springwater reflect a regular seasonal pattern of δ13C in DIC and Tufa specimens.
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Geochemical and hydrological controls on biannual lamination of Tufa deposits
Sedimentary Geology, 2008Co-Authors: Tatsuya Kawai, Akihiro Kano, Masako HoriAbstract:Abstract Fluvial Tufa deposits in southwest Japan commonly develop biannual lamination consisting of dense summer layers and porous winter layers, and the clearness of the laminae varies among the sites. The laminae have been largely attributed to a seasonally variable inorganic precipitation rate of calcite. This rate-controlled hypothesis was examined by using quantitative data for calcite packing-density (CPD) and the precipitation rate of calcite (PWP rate) calculated from water chemistry. The results for four Tufa-depositing sites in SW Japan show that a positive correlation between CPD and PWP rate becomes less certain with increasing PWP rate. In the temperature realm of SW Japan, Tufas develop regular distinct seasonal change in CPD when deposited in water containing Ca values less than 65 mg/l, which results in a relatively low precipitation rate. The CPD of Tufa deposits rarely exceeds 65%, owing to pore space between fine-grained calcite crystals and to porosity derived from decomposed cyanobacteria and other microorganisms. By increasing the Ca content to more than 65 mg/l, the CPD often attains an upper limit and becomes insensitive to seasonal changes in the PWP rate. Therefore, seasonal variations in CPD at sites with a higher Ca content are unclear, as seen in two examples from tropical islands in southern Japan and in one locality in a temperate climate. The flow rate and microbial density on the Tufa surface are subordinate factors with respect to the CPD. Seasonal changes in these two factors often enhance the porous/dense contrast of biannual lamination in SW Japan.
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seasonal patterns of carbon chemistry and isotopes in Tufa depositing groundwaters of southwestern japan
Geochimica et Cosmochimica Acta, 2008Co-Authors: Masako Hori, K Hoshino, Koji Okumura, Akihiro KanoAbstract:Abstract Annually laminated carbonates, known as Tufas, commonly develop in limestone areas and typically record seasonal patterns of oxygen- and carbon-isotope compositions. δ18O values are principally controlled by seasonal changes of water temperature, whereas δ13C values are the result of complex reactions among the gaseous, liquid, and solid sources of carbon in the system. We examined the processes that cause the seasonal patterns of δ13C in groundwater systems at three Tufa-depositing sites in southwestern Japan by applying model calculations to geochemical data. Underground inorganic carbon species are exchanged with gaseous CO2, which is mainly introduced to the underground hydrological system by natural atmospheric ventilation and by diffusion of soil air. These processes control the seasonal pattern of δ13C, which is low in summer and high in winter. Among the three sites we investigated, we identified two extreme cases of the degree of carbon exchange between liquid and gaseous phases. For the case with high radiocarbon composition (Δ14C) and low pCO2, there was substantial carbon exchange because of a large contribution of atmospheric CO2 and a small water mass. For the other extreme case, which was characterized by low Δ14C and high pCO2, the contribution of atmospheric CO2 was small and the water mass was relatively large. Our results suggest that at two of the three sites water residence time within the soil profile was longer than 1 year. Our results also suggested a short residence time (less than 1 year) of water in the soil profile at the site with the smallest water mass, which is consistent with large seasonal amplitude of the springwater temperature variations. The Δ14C value of Tufas is closely related to the hydrological conditions in which they are deposited. If the initial Δ14C value of a Tufa-depositing system is stable, 14C-chronology can be used to date paleo-Tufas.
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climatic conditions and hydrological change recorded in a high resolution stable isotope profile of a recent laminated Tufa on a subtropical island southern japan
Journal of Sedimentary Research, 2007Co-Authors: Akihiro Kano, Risa Hagiwara, Tatsuya Kawai, Masako Hori, Jun MatsuokaAbstract:Abstract The stable-isotope composition of a Tufa collected on subtropical Miyako Island, southern Japan, records climatic and hydrologic changes over a 15-year period (1989–2003). A total of 450 subsamples taken at increments of 0.2 mm define the high-resolution isotopic profile of a 9-cm-long sample. The oxygen isotope values clearly exhibit cyclical changes that generally correlate with the annual lamination pattern of the Tufa. The observed stability of water δ18O values confirms that the seasonal records of water temperature are reflected in the cyclic change of Tufa δ18O values. The oxygen isotope profile also exhibits a long-term decreasing trend that is equivalent to a 2.5°C temperature increase over the 15-year period. The range of the long-term change in δ18O values is at least partly compensated for by a warming trend of 0.95°C seen in metrological data for Miyako Island. However, the carbon isotope profile does not vary cyclically, and the values are clearly higher than for previously reported Tufas from the temperate Japanese mainland. Vegetation on Miyako Island, which is dominated by C4-type sugar cane, is largely responsible for the high δ13C values of the Tufa. The high-resolution isotopic profile provides data on the annual deposition rate, which clearly increased from 1996 to 1998, when the groundwater table was raised by the construction of two underground dams near the Tufa locality. Increased water flow from the spring activated calcite precipitation and increased the depositional rate in the upper part of the core up to > 1 cm/year. This rate is much larger than those recorded for Tufas from temperate settings in Japan.
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origin of annual laminations in Tufa deposits southwest japan
Palaeogeography Palaeoclimatology Palaeoecology, 2003Co-Authors: Akihiro Kano, Jun Matsuoka, Tomoko Kojo, Hidenori FujiiAbstract:Abstract Laminated Tufas and a Tufa-depositing stream in SW Japan (Shirokawa, Ehime Prefecture) were studied monthly over a 3-yr period. A series of samples from the Tufa clearly reveals the pattern of annual laminations. The annual layering pattern was primarily controlled by changes in the rate of calcite precipitation, as calculated from water chemistry. The concentration of dissolved CaCO 3 , which correlates with the precipitation rate, was high in summer–autumn and low in winter–spring, owing to changes in the partial pressure of CO 2 in underground air. Regular seasonal changes in underground PCO 2 probably resulted from two temperature-dependent processes, the diffusion of soil CO 2 and the ventilation of underground air. These changes, in addition to water temperature changes, altered the precipitation rate, which has a clear seasonal pattern, especially in the lower stream. The seasonal precipitation rate was high in summer–autumn and low in winter–spring, which is consistent with the seasonal lamination pattern seen in the Tufas. The textures of collected samples show that the laminations consist of densely calcified summer–autumn (June–October) laminae and lightly calcified winter–spring (November–May) laminae. We infer that the increased precipitation rate stimulated thick calcite encrustation on cyanobacterial filaments to produce the dense textures. This interpretation is supported by the lowered organic/inorganic carbon-production ratio in summer–autumn. Seasonal variations in cyanobacterial assemblages are present, but do not reflect the seasonal lamination pattern. Because the relevant processes are temperature dependent, the seasonal lamination pattern at Shirokawa is thought to generally apply to other laminated Tufas deposited in temperate climates. However, a reversed pattern can result from local and climatic circumstances. Dense laminae were deposited in winter near the source of the spring at Shirokawa, because calcite precipitation was high owing to low underground PCO 2 in winter. Reversed patterns reported from northwestern Europe were probably influenced by seasonal rainfall, which is reflected in hydrological conditions.
Gonzalo Pardo - One of the best experts on this subject based on the ideXlab platform.
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intrinsic and extrinsic controls of spatial and temporal variations in modern fluvial Tufa sedimentation a thirteen year record from a semi arid environment
Sedimentology, 2014Co-Authors: Concha Arenas, Marta Vazquezurbez, L F Auque, Carlos Sancho, C Osacar, Gonzalo PardoAbstract:Sedimentological and hydrochemical parameters of the River Piedra (north-east Spain) were monitored every six months (from 1999 to 2012) at 24 sites, at which tablets were installed all along the river. The river water is of HCO3–SO4–Ca type and is notably influenced by inputs from upstream karstic springs. Tufa deposition was first detected 8 km downstream of these springs and greatly increased from there, primarily along the steeper stretch (i.e. within the Monasterio de Piedra Natural Park); then, deposition decreased through the most downstream stretch, with smaller ground water inputs. The spatial evolution of the Tufa thickness, with parallel variations of PWP (Plummer, Wigley, Parkhurst) rates, was thus determined by the river water pCO2 which was controlled by ground water inputs and by the river bed slope. Five fluvial subenvironments and seven sedimentary facies were characterized. The water flow conditions are the primary factor responsible for the distinct deposition rates of facies, mainly through CO2-outgassing. Stromatolites and moss-Tufa and alga-Tufa had the highest rates, whereas loose Tufa formed in slow-flowing water and Tufa of spray areas had thinner deposition. A six-month pattern in the deposition rate was detected through thickness measurements. That pattern was parallel to the seasonal PWP rates. The increased deposition during warm periods (spring and summer; mean: 5·08 mm) compared with cool periods (autumn and winter; mean: 2·77 mm) is linked chiefly to temperature, which controlled the seasonal changes in the physico-chemical and biological processes; this finding is supported by a principal components analysis. Seasonal variations of insolation and day duration also contributed to such a deposition pattern. Large discharge events, which provoked erosion of Tufa deposits and dilution of water, caused the reversal of the seasonal deposition rate pattern. Stromatolites are likely to preserve the most complete sedimentary record. Although Tufas are a potentially sensitive record of climate-related parameters, erosion is an intrinsic process that may overwhelm the effects of such parameters. This issue should be considered in palaeoclimatic studies based on the Tufa record, particularly in semi-arid conditions.
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a sedimentary facies model for stepped fluvial Tufa systems in the iberian range spain the quaternary piedra and mesa valleys
Sedimentology, 2012Co-Authors: Marta Vazquezurbez, Concha Arenas, Gonzalo PardoAbstract:Stratigraphic and sedimentological analyses of the Quaternary Tufa and associated deposits in the Piedra and Mesa river valleys allowed a number of stages of their sedimentary evolution to be characterized, and a depositional sedimentary model for this north-central sector of the Iberian Range (Spain) to be established. The proposed sedimentary facies model may explain Tufa arrangements in other medium to high gradient, stepped, fluvial Tufa systems with narrow transverse profiles occurring in temperate, semi-arid areas, in both recent and past scenarios. There are several Tufa deposits within the Piedra and Mesa river valleys that, over a maximum thickness of about 90 m, record one or more stages of Tufa deposition produced following the fluvial incision of the bedrock or previous Tufa deposits. Each depositional stage begins with coarse detrital sedimentation. Six fundamental, vertical sequences of Tufa facies with small amounts of detrital material reveal the sedimentary processes that occurred in different fluvial environments: channel areas with: (i) free-flowing water; (ii) barrages and/or cascades; and (iii) dammed water and palustrine floodplains. The proposed sedimentary model involves narrow, stepped, fluvial valleys in which Tufa cascades were common. Alternating intervals of bryophyte and stromatolite facies commonly formed at some cascades. Many of these represented barrage-cascade structures that consisted of phytoclast rudstones, thick phytoherms of mosses and associated stromatolites, and curtain-shaped phytoherms of stems. Upstream of these structures, dammed areas with bioclastic sands and silts developed and palustrine vegetation grew. The channel stretches between barrages and/or cascades were loci for extensive stromatolite growth in fast flowing water. The palustrine floodplain was home to pools and drainage channels. The model also explains the growth of some barrages in the River Piedra that surpassed the height of the divide, with the diffluence of the main channel into a secondary course forming other Tufa deposits in the area. The distribution and abundance of certain types of Tufa facies in fluvial basins may be an indicator of differences in their gradients. The facies studied in this work suggest that the gradient of the ancient River Piedra was steeper than that of the ancient River Mesa. Assuming similar scenarios for climate and hydrology, the depositional settings mentioned above and their dimensions would have been determined mainly by the gradient and width of the associated river valleys. This sedimentary model may also be useful for inferring variations in other river basin slopes, as well as accounting for the presence of Tufas in areas that normally have no permanent water input.
Julie Dabkowski - One of the best experts on this subject based on the ideXlab platform.
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The late-Holocene Tufa decline in Europe: Myth or reality?
Quaternary Science Reviews, 2020Co-Authors: Julie DabkowskiAbstract:Abstract In 1993, Goudie and co-authors named the postulate that there would be a marked decline in the deposition of calcareous Tufa in Europe since ca. 2500 BP ‘the late-Holocene Tufa decline’. However, the growing development of investigation on calcareous Tufas and considerable improvement in dating methods, especially radiocarbon dating, has provided reliable evidence of deposits developing until our present days. I thus discuss the reality of the decline, reviewing 62 Tufa sites in Europe and their time distribution based both on radiocarbon dates and biochronological data and distinguishing different cases depending on Tufa size and types. I demonstrate that the late-Holocene Tufa decline is actually a general view of a rather complex tendency: after a maximum during the Atlantic period, fluvial Tufas are systematically affected by a decline from ca. 5 ka cal. BP but no general trend is shown in the development of proximal (spring-fed) or lacustrine Tufas. This observation is likely to result from the increasing impact of human activity (mainly deforestation) on landscapes, and more specifically on fluvial environments, from the Bronze Age.
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high resolution δ18o seasonality record in a french eemian Tufa stromatolite caours somme basin
Palaeogeography Palaeoclimatology Palaeoecology, 2015Co-Authors: Julie Dabkowski, Pierre Antoine, A Marcabell, Samuel Royle, J E AndrewsAbstract:Abstract Recent and sub-recent laminated Tufa stromatolites can contain high-resolution δ18O records of in-stream temperature change. Fossil Tufa stromatolites are therefore key targets for reconstructing terrestrial palaeoclimatic, but so far only a few examples have been published. In this research, we studied a 2.5-cm-radius Tufa stromatolite from the Eemian of the Somme Basin, Northern France. We show (1) that high-resolution sampling of fossil laminated Tufas is highly reproducible. We demonstrate (2) that within the limitations of the δ18O method, NW European Eemian seasonality was essentially similar to the present day. Perhaps most important, we show (3) that precise observations from thin section that match the position of lamina boundaries with the position of reversals in direction of δ18O values are a record of the style or intensity of seasonality. In this French Tufa stromatolite, abrupt δ18O reversals do not coincide with sharp lamina boundaries; rather, the lamina boundaries occur where δ18O values are either gradually decreasing or increasing. We interpret this to be a record of abrupt changes in the growth rate, accelerating in spring or early summer and decelerating in late autumn or early winter. This contrasts with a published montane record from the Eemian of Greece, where lamina boundaries and δ18O reversals do coincide, interpreted as more extreme seasonality caused by cessations in growth due to summer aridity or winter cold. We thus propose this criterion as a method to help identify regional styles of seasonality in Tufa stromatolites.
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stable isotope record of eemian seasonal temperature from mis 5e Tufa stromatolite somme basin northern france
Climate of The Past Discussions, 2013Co-Authors: Julie Dabkowski, Pierre Antoine, J E Andrews, A MarcabellAbstract:Abstract. In many modern to sub-fossil deposits Tufa formations, very well crystallised deposits called stromatolites are preserved. These are often strongly laminated deposits, the laminae linked to seasonal climatic and environmental variations. Where found in fossil Tufas such deposits have huge potential as high resolution archives of Pleistocene climate. One of the first investigations of this type has been performed on a 2.5 cm-radius stromatolite from the Eemian sequence of Caours (Somme Basin, Northern France), where precise observations in thin section have been combined with intra-lamina δ18O and δ13C analyses. Independent interpretations of petrographical and geochemical data are strongly coherent and demonstrate a clear seasonal signal. Moreover, as δ18O is temperature dependent, we have quantified likely maximum water temperature variations between summer and winter at Caours. A small mismatch between the δ18O derived temperature values and the typical modern range is observed, which may reflect a real difference between modern and Eemian temperature seasonality. This study supports previous investigations performed on a laminated Tufa from central Greece and clearly confirms the potential of Tufa stromatolites as records of seasonal climatic information and for the quantification of riverine water temperature variations.
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climatic variations in mis 11 recorded by stable isotopes and trace elements in a french Tufa la celle seine valley
Journal of Quaternary Science, 2012Co-Authors: Julie Dabkowski, Nicole Limondinlozouet, Pierre Antoine, J E Andrews, A Marcabell, Vincent RobertAbstract:Marine Isotope Stage (MIS) 11 palaeoclimate has so far been documented in marine and ice sheet isotopic records. However, excepting some lacustrine pollen records, very little is known about palaeoclimatic conditions in continental areas. This study uses geochemical records in calcareous Tufa deposits from rivers as a basis for reconstructing temperate palaeoclimatic conditions. Tufa deposits are now proven to record high-quality palaeoclimatic information in recent to Holocene deposits. Work on older interglacial Tufas is just starting and in this paper we present the first comprehensive results from a MIS 11 Tufa. The Tufa comes from the Seine Valley (La Celle, northern France). Geochemical data in the Tufa calcite are interpreted to record primarily air temperature (dO) and humidity (dC and Mg/Ca and Sr/Ca). The combined data identify a warm and wet climatic optimum followed by two temperature decreases associated with oscillations in humidity. These marked climatic variations recorded through the La Celle profile are strongly coherent with the palaeoenvironmental reconstructions from malacological data. The abrupt climatic and environmental events recorded could be related to short-term degradation of vegetation cover in Europe, which is itself controlled by global palaeoclimatic events.
J E Andrews - One of the best experts on this subject based on the ideXlab platform.
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high resolution δ18o seasonality record in a french eemian Tufa stromatolite caours somme basin
Palaeogeography Palaeoclimatology Palaeoecology, 2015Co-Authors: Julie Dabkowski, Pierre Antoine, A Marcabell, Samuel Royle, J E AndrewsAbstract:Abstract Recent and sub-recent laminated Tufa stromatolites can contain high-resolution δ18O records of in-stream temperature change. Fossil Tufa stromatolites are therefore key targets for reconstructing terrestrial palaeoclimatic, but so far only a few examples have been published. In this research, we studied a 2.5-cm-radius Tufa stromatolite from the Eemian of the Somme Basin, Northern France. We show (1) that high-resolution sampling of fossil laminated Tufas is highly reproducible. We demonstrate (2) that within the limitations of the δ18O method, NW European Eemian seasonality was essentially similar to the present day. Perhaps most important, we show (3) that precise observations from thin section that match the position of lamina boundaries with the position of reversals in direction of δ18O values are a record of the style or intensity of seasonality. In this French Tufa stromatolite, abrupt δ18O reversals do not coincide with sharp lamina boundaries; rather, the lamina boundaries occur where δ18O values are either gradually decreasing or increasing. We interpret this to be a record of abrupt changes in the growth rate, accelerating in spring or early summer and decelerating in late autumn or early winter. This contrasts with a published montane record from the Eemian of Greece, where lamina boundaries and δ18O reversals do coincide, interpreted as more extreme seasonality caused by cessations in growth due to summer aridity or winter cold. We thus propose this criterion as a method to help identify regional styles of seasonality in Tufa stromatolites.
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stable isotope record of eemian seasonal temperature from mis 5e Tufa stromatolite somme basin northern france
Climate of The Past Discussions, 2013Co-Authors: Julie Dabkowski, Pierre Antoine, J E Andrews, A MarcabellAbstract:Abstract. In many modern to sub-fossil deposits Tufa formations, very well crystallised deposits called stromatolites are preserved. These are often strongly laminated deposits, the laminae linked to seasonal climatic and environmental variations. Where found in fossil Tufas such deposits have huge potential as high resolution archives of Pleistocene climate. One of the first investigations of this type has been performed on a 2.5 cm-radius stromatolite from the Eemian sequence of Caours (Somme Basin, Northern France), where precise observations in thin section have been combined with intra-lamina δ18O and δ13C analyses. Independent interpretations of petrographical and geochemical data are strongly coherent and demonstrate a clear seasonal signal. Moreover, as δ18O is temperature dependent, we have quantified likely maximum water temperature variations between summer and winter at Caours. A small mismatch between the δ18O derived temperature values and the typical modern range is observed, which may reflect a real difference between modern and Eemian temperature seasonality. This study supports previous investigations performed on a laminated Tufa from central Greece and clearly confirms the potential of Tufa stromatolites as records of seasonal climatic information and for the quantification of riverine water temperature variations.
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climatic variations in mis 11 recorded by stable isotopes and trace elements in a french Tufa la celle seine valley
Journal of Quaternary Science, 2012Co-Authors: Julie Dabkowski, Nicole Limondinlozouet, Pierre Antoine, J E Andrews, A Marcabell, Vincent RobertAbstract:Marine Isotope Stage (MIS) 11 palaeoclimate has so far been documented in marine and ice sheet isotopic records. However, excepting some lacustrine pollen records, very little is known about palaeoclimatic conditions in continental areas. This study uses geochemical records in calcareous Tufa deposits from rivers as a basis for reconstructing temperate palaeoclimatic conditions. Tufa deposits are now proven to record high-quality palaeoclimatic information in recent to Holocene deposits. Work on older interglacial Tufas is just starting and in this paper we present the first comprehensive results from a MIS 11 Tufa. The Tufa comes from the Seine Valley (La Celle, northern France). Geochemical data in the Tufa calcite are interpreted to record primarily air temperature (dO) and humidity (dC and Mg/Ca and Sr/Ca). The combined data identify a warm and wet climatic optimum followed by two temperature decreases associated with oscillations in humidity. These marked climatic variations recorded through the La Celle profile are strongly coherent with the palaeoenvironmental reconstructions from malacological data. The abrupt climatic and environmental events recorded could be related to short-term degradation of vegetation cover in Europe, which is itself controlled by global palaeoclimatic events.
John Webb - One of the best experts on this subject based on the ideXlab platform.
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climatic significance of seasonal trace element and stable isotope variations in a modern freshwater Tufa
Geochimica et Cosmochimica Acta, 2003Co-Authors: Christian Ihlenfeld, Marc D Norman, Michael K Gagan, Russell N Drysdale, Roland Maas, John WebbAbstract:Abstract We present a continuous ∼14-yr-long (1985 to 1999) high-resolution record of trace element (Mg, Sr, Ba, U) and stable isotope (δ13C, δ18O) variations in a modern freshwater Tufa from northwestern Queensland, Australia. By utilizing the temperature dependence of the δ18O signal, an accurate chronology was developed for the sampled profile, which allowed a comparison of the chemical records with hydrological and meteorological observations. As a consequence, it was possible to constrain the relevant geochemical processes relating climate variables, such as temperature and precipitation, to their chemical proxies in the Tufa record. Temperatures calculated from the Mg concentrations of the Tufa samples provide close approximations of average annual water temperature variations. Furthermore, we demonstrate that temporal changes in (Mg/Ca)water can be estimated using an empirically derived equation relating (Mg/Ca)water to the (Sr/Ba) ratio measured in the Tufa samples. By means of this relationship, it is theoretically possible to determine the (Mg/Ca) ratio of paleowaters, and hence to derive reliable estimates of former water temperatures from the Mg concentrations of fossil Tufas from the study area. Sympathetic variations in Sr, Ba, and δ13C along the sampled profile record changes in water chemistry, which are most probably caused by variable amounts of calcite precipitation within the vadose zone of the karst aquifer. This process is thought to be markedly subdued whenever the amount of wet-season precipitation exceeds a given threshold. Accordingly, distinct minima in Sr, Ba, and δ13C are interpreted to reflect years with above-average rainfall. The pronounced seasonal and annual variability of the U concentration along the profile is thought to primarily record changes in the U flux from the soil to the water table. We suggest that during intensive rain events U is transported to the phreatic zone by complexing organic colloids, giving rise to conspicuous U maxima in the Tufa after above-average wet seasons. This study demonstrates the potential of freshwater Tufas to provide valuable information on seasonal temperature and rainfall variations. If Tufa deposits turn out to be reasonably resistant to secondary processes, combined investigation of speleothems and Tufas from the same area could become a promising approach in future research. While speleothems offer continuous records of long-term paleoenvironmental changes, Tufas could provide high-resolution time windows into selected periods of the past.
