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Between 1979 and 2003, a 35 cm thick layer of laminated tufa formed around a wooden pillar located at the beginning of the Korana River, which emerges from the Plitvice Lakes, Croatia. The laminated tufa structure allowed for the stratigraphic analysis of mineral, elemental and δ18O and δ13C isotope composition. Results are compared to other carbonate archives (lake sediments) from the Plitvice Lakes and to measured water physical–chemical data collected in the same time. An increase in water temperature and decrease in Mg/Ca ratio was observed during that period. Results showed that the tufa Mg/Ca ratio and δ18O could not be used as a temperature proxy, while an observed δ18O increase after 1990 was attributed to increase in evaporation rate. Furthermore, the constant increase in redox-sensitive elements (Mn) towards the external part of tufa may indicate periodic events of anoxia at the sediment/water interface. Local enrichment factors (LEFs) for potentially toxic elements were calculated using the background function and Al as the normalizing element. The LEFs showed an enrichment pattern of Cu and Pb in 1983 and 2001, which could indicate their anthropogenic origin and the sensitivity of the tufa to environmental changes.

In the Mediterranean area, the 4.2 ka BP event is recorded with contrasting expressions between regions. In the southern Alps, the high-altitude Lake Petit (Mercantour Massif, France; 2200 a.s.l.) offers pollen and diatom-rich sediments covering the last 4800 years. A multi-proxy analysis recently revealed a detrital pulse around 4200 cal BP due to increasing erosion in the lake catchment. The involvement of a rapid climate change leading to increasing runoff and soil erosion was proposed. Here, in order to clarify this hypothesis, we measured the oxygen isotope composition of diatom silica frustules (delta O-18(diatom)) from the same sedimentary core. Diatoms were analysed by laser fluorination isotope ratio mass spectrometry after an inert gas flow dehydration. We additionally enhanced the accuracy of the age-depth model using the Bacon R package. The delta O-18(diatom) record allows us to identify a 500-year time lapse, from 4400 to 3900 cal BP, where delta O-18(diatom) reached its highest values (> 31 parts per thousand). delta O-18(diatom) was about 3 parts per thousand higher than the modern values and the shifts at 4400 and 3900 cal BP were of similar amplitude as the seasonal delta O-18(diatom) shifts occurring today. This period of high delta O-18(diatom) values can be explained by the intensification of O-18-enriched Mediterranean precipitation events feeding the lake during the ice-free season. This agrees with other records from the southern Alps suggesting runoff intensification around 4200 cal BP. Possible changes in other climatic parameters may have played a concomitant role, including a decrease in the contribution of O-18-depleted Atlantic winter precipitation to the lake water due to snow deficit. Data recording the 4.2 ka BP event in the northwestern Mediterranean area are still sparse. In the Lake Petit watershed, the 4.2 ka BP event translated into a change in precipitation regime from 4400 to 3900 cal BP. This record contributes to the recent efforts to characterize and investigate the geographical extent of the 4.2 ka BP event in the Mediterranean area.

This thesis is focused on the Attico-Cycladic orogenic wedge formed during the Alpine orogeny. From a multi-method and multi-scale approach using structural geology, petrography, mineral thermobarometry, element and isotope geochemistry, and PVTX data of associated fluid inclusions, this study deciphers the relationships between fluid circulation, fluid-rock interactions and mobilisation-transport-deposits of metals. Marbles and schists from the Evia Island and the Lavrion peninsula testify to a complex orogenic history marked by an Eocene burial phase followed by syn- and post-orogenic exhumation. Cu-Pb-Zn-Fe-Ag mineralisations from the Lavrion area are synchronous with the formation of the low-angle post-orogenic detachment and the emplacement of granodioritic magmas. The structural position of the deposits attests of an emplacement during ductile to brittle deformation conditions. Deposits associated with ductile to ductile-brittle deformation (skarn, carbonate replacement) are related to a marble decarbonation and magmatic fluid circulation. The progressive exhumation of the orogenic wedge allows the transition toward brittle conditions and opens the system to surficial meteoritic fluids. This meteoritic fluid circulation is responsible to remobilisation of metals from primary deposits allowing thus a second phase of deposition in a pure brittle deformation (epithermal veins), Cette thèse est centrée sur la ceinture orogénique Attico-Cycladique formée durant l'orogénèse Alpine. Par une approche multi-méthodes et multi-échelles combinant géologie structurale, pétrographie, thermobarométrie des assemblages minéraux, géochimie élémentaire et isotopique, et données PVTX des inclusions fluides associées, ce travail vise à caractériser et comprendre les relations entre circulations fluides, interactions fluides/roches, déformation, et mobilisation-transport-dépôt des métaux. Les marbres et schistes de la péninsule du Lavrion et de l'île d'Eubée témoignent d'une évolution orogénique complexe marquée par une phase d'enfouissement à l'Eocène suivie par deux phases d'exhumation successives syn-et post-orogéniques. Les minéralisations de type Cu-Pb-Zn-Fe-Ag de la région du Lavrion sont synchrones de l’activation du détachement post-orogénique et de la mise en place de plutons de granodiorite. Leurs positions structurales témoignent d’un piégeage depuis un régime de déformation ductile jusqu'à fragile. Les minéralisations mises en place durant le régime de déformation ductile à ductile-fragile (skarn et remplacement de carbonate) sont associées à la décarbonatation des niveaux de marbres et à la circulation des fluides magmatiques. L'exhumation progressive de la racine orogénique se traduit par la transition des roches depuis une déformation ductile vers un régime fragile associé à l’ouverture du système aux fluides de surface et notamment aux fluides météoriques. Cette circulation est responsable d’une remobilisation des métaux des minéralisations primaires permettant alors une seconde phase de précipitation dans un régime cassant (veines épithermales)

In meat production it is common practice to use finishing diets based on concentrates, even for those animals previously raised on pasture. No studies have investigated the variations of stable isotope ratios in lamb plasma and erythrocytes, following a switch from pasture to a concentrate-based diet during the last days before slaughter. For meat traceability it is important to verify how and whether these parameters are affected in blood fractions.Blood of ten male Italian Merino lambs, whose diet was switched from pasture to concentrate, was sampled 8 times (days 1, 2, 3, 4, 5, 6, 7 and 14) in the last 14 days before slaughter. The variations in the δ(13)C, δ(15)N, δ(18)O and δ(34)S values of blood plasma and erythrocytes were investigated. The stable isotope ratios of the samples were measured using a stable isotope mass spectrometer coupled with an elemental analyser (C, N, S) and a CO2/H2O equilibration system (O(plasma)).The δ(13) C(plasma), δ(18)O(plasma) and δ(34)S(plasma) values were shown to be different 7 days after the abrupt variation in the diet. The comparison between erythrocytes and plasma stable isotope ratios could be suitable for verifying whether the animal was actually pasture-raised and could merit a higher price. The erythrocytes isotopic signature was not affected by very short finishing periods in previously grazed animals and maintained the pasture-raised fingerprint, while the analysis of plasma could detect very short finishing periods with concentrate and hay.The present study has demonstrated that the combination of blood plasma and erythrocytes stable isotope ratios of carbon, nitrogen, oxygen and sulphur can be used to infer the dietary background of lambs and thus offers a tool for the authentication of the animal production system.

International audience; Fluid inclusions represent a unique opportunity for a straightforward determination of the chemical and isotopic composition of fluids that composed the hydrosphere and atmosphere over Earths history. The production of reference materials in the laboratory is needed to monitor and to validate the determination of hydrogen and oxygen isotope compositions of water inclusions. We propose a protocol leading to the experimental synthesis of halite crystals that contain water inclusions whose dD and d18O values can be related to those of surrounding evaporating waters where the crystals grew. Corrections to isotopic measurements were performed by applying an orthogonal projection of the raw data to the water evaporation trajectory line whose slope can be predicted by taking into account the parameters developed in the linear resistance model of Craig and Gordon (1965). Several hundreds of grams of halite reference material can be produced rapidly (within 2 d) at a low cost and can be stored within a vacuum desiccator at ambient temperature over several months or years. The described method is especially useful for the analysis of anhydrous salts and the interpretation of isotopic fractionations that operate within the surficial water cycle.

An annual laminated stalagmite from northern Spain recorded two outstanding oxygen isotope (δ18O) pulses during the 8.2 ka event. Most of the oxygen isotope record variability is related to the amount of rainfall, although other factors affect the signal. The lamina thickness record, which is also related to amount of rainfall, does not show any significant anomaly at the time of oxygen isotope spikes. Considering the factors affecting the isotope signal, the two prominent falls in δ18O during the event are interpreted to be caused by the release of large amounts of fresh waters into the North Atlantic. Thus, 18O-depleted ocean surface waters shifted the rainfall δ18O composition for Europe and Greenland. Our precise chronology provides the timing of the outbursts that caused the δ18O anomalies at 8350–8340 and 8221–8211 ± 34 yr B.P., most probably generated by the drainage of proglacial lakes Agassiz and Ojibway. Therefore, in the North Atlantic region δ18O records during the 8.2 ka event trace important hydrological modifications in the ocean, not just local climate. As a consequence, paleoclimate reconstructions from Europe and Greenland using the δ18O proxy that does not take this into account would be overestimating the magnitude of the anomalies during the 8.2 ka event.

Stabilni izotopi vodika i kisika se kao obilježivaci vode i procesa koje ona prolazi koriste vec dugi niz godina. Prepoznati su u mnogim podrucjima kao pouzdano i primjenjivo orude u pracenju procesa u hidrologiji, biologiji, meteorologiji. Odabrano podrucje ovog istraživanja je Republika Hrvatska. Kompleksnost klimatskih uvjeta i raznovrsnost reljefa utjecu na konacni izotopni sastav oborine. Da bi se obuhvatila varijabilnost izotopnog sastava cijelog podrucja istraživanja potreban je velik broj opažackih postaja. Sakupljani su mjesecni podatci na 54 postaje tijekom minimalno jedne godine do maksimalno pet godina. Izotopni sastav vodika (d2H) i kisika (d18O) iz uzoraka oborine odreden je u Laboratoriju za stabilne izotope u Rijeci, metodom masene spektroskopije. Analizom podatka i izradom lokalne linije meteorske vode svake pojedine postaje pokazano je da se Hrvatska može podijeliti na specificna podrucja koja odražavaju razlicita klimatska obilježja. Daljnjom analizom uoceni su sezonski utjecaj i utjecaj nadmorske visine, takoder razliciti na razlicitim podrucjima. Najveca razlika uocena je izmedu kontinentalnog i obalnog dijela. Kako bi se dobila prostorna raspodjela delta vrijednosti kisika u oborini citavog podrucja istraživanja napravljeno je modeliranje. U zasebnom poglavlju analiziran je suvišak deuterija kao parametar kojim se odreduje porijeklo oborinskih zracnih masa. U podrucju hidrologije stabilni izotopi se kao obilježivaci primjenjuju za odredivanje velicine i srednje visine napajanja vodonosnika. Takoder su primjenjivi u razvedenim krškim vodonosnicima cije ocuvanje i razumijevanje je važno radi vodoopskrbe.

Stable oxygen isotopes (d18O) from human bone apatite from central western Argentina (30º–37ºS latitude) were analysed to understand changes in human residential mobility during the Late Holocene. This region contains evidence for the use of domesticated plants over the last 2000 years (Zea mays, Cucurbita sp. and Phaseolus sp., among others), and previous models of prehistoric occupation have suggested a distinct change in mobility and population movement associated with their incorporation. The importance of these domesticates also seems to have varied geographically, being greater in the northern part of the region and declining as one moves south toward the limit with Patagonia. Expectations about patterns of residential mobility have varied accordingly. To better evaluate these models, we analysed carbonate d18O from the bone apatite of 71 individuals with radiocarbon dates spanning the last 6000 years. Given the existing evidence, we expected to see temporal and geographic differences in their oxygen isotope values associated with changes in residential mobility and the incorporation of different sources of drinking water available within the region. These expectations were not met. Significant variations were seen across all samples compared, both temporal and geographic, with no discernible differences among them. The data suggest that populations throughout the area were all highly mobile, and that this did not change with the incorporation of domesticates. Fil: Gil, Adolfo Fabian. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Neme, Gustavo Adolfo. Museo Municipal de Historia Natural San Rafael - Unidad Asociada al CCT Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ugan, Andrew. Smithsonian Tropical Research Institute; Panamá Fil: Tykot, Robert H.. University of South Florida. Department of Anthropology; Estados Unidos

In this paper, we investigate whether the analysis of stable isotope ratios D/H and ¹³C/¹²C in ethanol and acetic acid and of ¹⁸O/¹⁶O in water can be applied to the ingredients of "aceto balsamico di Modena IGP" (ABM) to evaluate their authenticity. We found that impurities in the extraction solution do not affect the ¹³C/¹²C of acetic acid and the D/H values of acetic acid are not affected under a composite NMR experiment. The standard deviation of repeatability and standard deviation of reproducibility are comparable in wine vinegar and ABM and generally lower than those quoted in the official methods. This means that the validation parameters quoted in the official methods can also be applied to the ingredients of ABM. In addition, we found no changes in the isotopic values from wine to vinegar and to ABM, and from the original must to the ABM must, providing experimental evidence that reference data from wine databanks can also be used to evaluate the authenticity of vinegar and ABM.

The goal of this paper was to characterize the recharge process and water–rock interactions in a regional homogeneous fractured carbonate aquifer in the Mediterranean environment (Gran Sasso, central Italy) through isotope data (δ2H, δ18O and δ13C-DIC) collected between 2006 and 2010. Samples were collected from the springs of the Gran Sasso aquifer and from the Underground Nuclear Physics Laboratories, located within the aquifer. Additionally, the hydrochemical data and the reference hydrogeological frameworks of previous studies have been used as a starting point for the geochemical modeling. The Gran Sasso aquifer, which is bounded by terrigenous and clastic units acting as aquitards, accommodates a uniquely broad regional groundwater, which feeds springs mainly at its border with high, steady discharge. In total, these springs discharge of more than 18 m3/s. At a local scale for the aquifer core and at a regional scale for the overall aquifer, δ 2H, δ18O and δ13C-DIC isotope data, the geochemical inverse modeling through PHREEQC and the δ13C-DIC fractionation modeling through NETPATH 2.0 show the following. (1) Clear processes of evaporation and related isotope enrichment may be ruled out. (2) Groundwater flow is active and extends to the overall aquifer without clear signs of layering and partitioning. (3) Groundwater flowpaths radiate from the core toward the periphery. (4) In L’Aquila Plain, Gran Sasso groundwater mixes with shallow Quaternary water at a ratio of one half. (5) The main geochemical processes are the dissolution of calcite and dolomite, and in some cases, ion exchange occurs (Mg2+ and SO42− release, Ca2+ adsorption). (6) In the less mineralized recharge groundwater, the δ13C-DIC value is influenced by the δ13C-DIC value of rainfall, while in more evolved groundwater, the final δ13C-DIC value is reached by fractionation during the flowpaths, indicating a lengthy interaction with limestone.

Our study aims to define isotopic and anatomical responses to fires of P. halepensis . Main results: decrease in tree growth and relative conductivity and increase in water use efficiency. We investigated the ecophysiological responses of a Pinus halepensis Mill. stand surviving two wildfires in southern France. Basal area, isotope composition and anatomical traits were analysed before and after fires, using tree rings to assess the ecological responses of trees to heat-related damage. The years were determined based on the presence of fire scars. Stable isotopes (δ13C and δ18O) were measured in tree rings before and after the “fire years”. Anatomical observations allowed qualitative analysis of the scar region and quantification of tracheid size in tree rings before and after the fire years. Relative and percentage conductivity of earlywood and latewood far from the woundwood were estimated. Results showed a decrease in tree growth after the fire events accompanied by an increase in 13C-derived water use efficiency (WUEi) and a decrease in relative conductivity. The positive relationship between δ13C and δ18O suggested that both isotopic variations are mostly driven by changes in stomatal conductance following fire events. P. halepensis proved to be a strong isohydric species, able to survive frequent fires with temporary ecophysiological modifications and anatomical adaptations. Our findings afford new insights into post-fire survival strategies of this species in an environment where fires are predicted to increase in frequency during the twenty-first century.

Recently, calcareous cyst producing dinoflagellates, and especially the species Thoracosphaera heimii, have gained more interest in paleoenvironmental and paleoclimatic studies. This PhD thesis focuses on the stable oxygen isotope composition (d18O) and minor element to calcium ratios (Mg/Ca and Sr/Ca) of T. heimii shells from surface sediments in different oceanographic regions. An attempt was made to link d18O, Mg/Ca and Sr/Ca of T. heimii shells with environmental parameters of the upper water column, especially temperature and the carbonate chemistry of the seawater.

Two Holocene sediment cores from the southern flank of the Skagerrak are investigated for the stable oxygen and carbon isotopic composition of benthic foraminiferal tests and faunal assemblages. Core 225514 was recovered from 420 m and Core 225510 from 285 m water depth.The stable oxygen isotopic composition of Bulimina marginata tests in Core 225514 is demonstrated to indicate Skagerrak deep-water renewal during the last 1200 years. Since deep-water renewal is characterized by sudden dropsin temperature and salinity, and since δ18O values reflect both temperature and salinity changes, the influences of the two parameters have to be evaluated separately. By comparing the measured δ18O variability with a salinity-δ18O mixing line valid for marine to brackish Scandinavian waters, it was shown that salinity changes are responsible for maximal 9 % of the total δ18O variability. Correlationof temperature monitoring data with the North Atlantic Oscillation (NAO) index reveals that Skagerrak deep-water renewal is triggered by the negative phase of the NAO. During highly negative index phases very cold and calm conditions prevail over the North Sea. Central North Sea water masses are cooled down strongly and hence reach densities, which are higher than those of the deep Skagerrak water masses. Occasionally, these dense water masses start to cascade into the Skagerrak.The stable carbon isotopic composition of benthic foraminiferal tests is used to investigate the organic matter flux to the seafloor and the oxygen availabilitywithin the sediments as well as to approach microhabitat-corrected vital effects of four species. The δ13C values of Uvigerina mediterranea indicate that the flux of organic matter to the seafloor was relatively constant between AD 1500 and 1950 and increased after AD 1950. We suggest that this increase in organic matter flux to the seafloor results from hydro-climatic variability within the North Sea region. A persistently high NAO index during the 1980s and 1990s enhanced the influx of nutrient-rich water masses through the English Channel. In concurrence with high temperatures, these nutrient-rich water masses allowed for increased primary productivity within the North Sea and presumably also within the Skagerrak-Kattegat region.The comparison of reconstructed δ13C gradients of dissolved inorganic carbon (DIC) within the two investigated cores indicates that organic matterremineralization due to respiration was generally enhanced in Core 225514 compared to Core 225510. Since the flux of organic matter to the seafloor was similar at both core sites and both sites were bathed by the same water mass, it is suggested that oxygen availability within the sediments is responsible for the difference. Higher sedimentation rates at Site 225510 result in enhanced carbon burial due to lower oxygen exposure times. The influence of oxygen exposure times on δ13C values should be especially important in shelf environments because sedimentation rates might be very variable there. Minimum estimates of microhabitat-corrected vital effects with reference to Globobulimina turgida are determined for Hyalinea balthica (> 1.3 �), Cassidulina laevigata (> 0.7 �), and Melonis barleeanus (> 0.7 �). Melonis zaandami seems to calcify its test close to pore water δ13CDIC.Faunal investigations produced three clearly distinguishable assemblages for each investigated core. In Core 225514 these assemblages occur consecutively, whereas the assemblages in Core 225510 intermittently change. The chronological order of dominant species in Core 225514 reflects the lateral succession of dominant species in modern surface sediments from the basin margin to the deepSkagerrak. For each dominant seasonal-phytophagous species a Gaussian-like relationship between species frequencies and specific sedimentary total organic carbon (TOC) contents is demonstrated. We propose that the chronologicalspecies succession in Core 225514 is the result of increasing sedimentary TOC contents with time, whereas the intermittently changing assemblages in Core 225510 are attributed to the vertically changing position of the Northern Jutland Current.

We present the first European network of tree ring delta(13)C and delta(18)O, containing 23 sites from Finland to Morocco. Common climate signals are found over broad climatic-ecological ranges. In temperate regions we find positive correlations with summer maximum temperatures and negative correlations with summer precipitation and Palmer Drought Severity Indices (PDSI) with no obvious speciesspecific differences. Regional delta(13)C and delta(18)O chronologies share high common variance in year-to-year variations. Long-term variations, however, exhibit differences that may reflect spatial variability in environmental forcings, age trends and/or plant physiological responses to increasing atmospheric CO(2) concentration. Rotated principal component analysis (RPCA) and climate field correlations enable the identification of four sub-regions in the delta(18)O network - northern and eastern Central Europe, Scandinavia and the western Mediterranean. Regional patterns in the delta(13)C network are less clear and are timescale dependent. Our results indicate that future reconstruction efforts should concentrate on delta(18)O data in the identified European regions.

The radioactive waste geological storage research is conducted, in France, in Callovo-Oxfordian argillites (Eastern Paris Basin). The origin and the story of the water present in this low permeable clayrock is a major problem since it is the vector of radioactivity towards biosphere. Different geochemical tracers (ΔD, Δ18O, 87Sr/86Sr and noble gas contents) are used here to understand the origin and the story of the pore water. The main difficulty lies in the impossibility to extract water, having made necessary the elaboration of rigorous analytical protocols. The obtained results are confronted with geochemical analysis of the groundwaters of the limestones formations surrounding the argillites. Waters origins and interactions with rocks that they are or were in contact constitute the interest of this work. The analysis of the argillites texture by gas adsorption allow besides studying their porosity, their adsorption capacity as well as their behavior to hydration. The argillite pore waters appear to be of meteoric origin, significant that sea waters originally present were replaced by meteoric waters. The groundwaters of the two limestone formations surrounding the argillites present distinct geochemical signatures, revealing the role of screen played by the impermeable argillite layer., La recherche sur le stockage de déchets radioactifs en formation géologique profonde est conduite, en France, dans les argilites du Callovo-Oxfordien (Est du Bassin de Paris). L'origine et l'histoire de l'eau présente dans cette roche argileuse peu perméable est une problématique majeure alors qu'il s'agit du vecteur de radioactivité vers la biosphère. Différents traceurs géochimiques (ΔD, Δ18O, 87Sr/86Sr et teneurs en gaz rares) sont utilisés ici pour comprendre l'origine et l'histoire de l'eau porale. La principale difficulté réside dans l'impossibilité d'extraire l'eau des argillites, ayant rendu nécessaire la mise au point de protocoles analytiques rigoureux adaptés à ce type de roches. Les résultats obtenus sont confrontés aux analyses géochimiques des eaux des formations calcaires qui encadrent les argilites. Les origines des eaux et les interactions avec les roches avec lesquelles elles sont ou ont été en contact constituent l'intérêt de ce travail. L'analyse de la texture des argilites par adsorption de gaz permet en outre d'étudier leur porosité, leur capacité d'adsorption ainsi que leur comportement à l'hydratation. Les eaux porales des argilites s'avèrent être d'origine météorique, ce qui signifie que les eaux marines originellement présentes ont été envahies par des eaux météoriques, probablement par diffusion. Les eaux des deux formations calcaires encadrant les argilites présentent des signatures géochimiques distinctes, révélant le rôle d'écran joué par la couche imperméable des argilites.

Burial-induced and hydrothermal-related illitization in bentonites and in sandstones can be modeled on the basis of isotopic studies of fundamental particles separated from mixed-layer illitesmectite. The model envisages different reaction rates and durations relative to the varied impacts of temperature, considering that the water:rock ratio also has an influence. The different pathways for illitization are suggested on the basis of the K-Ar, Rb-Sr and δ18O compositions of previously studied materials. New information is provided on why fundamental particles separated from mixed-layer illite-smectite in shales yield K-Ar age data that are systematically greater than the ages of the fundamental particles from associated bentonites and/or sandstones, and greater than the reported stratigraphic ages. The study of pure authigenic, recent to present-day smectite from Pacific sediments shows that (1) those collected from active hydrothermal vents have 40Ar/36Ar ratios identical to that of the atmosphere, and (2) those of mud sediments have 40Ar/36Ar ratios above the atmospheric value, indicating addition of 40Ar not generated in situ by radioactive decay. A preliminary but detailed analysis of the noble-gas (Ar, Xe, Kr) contents of authigenic smectite-rich size fractions from Pacific deep-sea red clays suggests trapping of these gases by smectite. Therefore, the results point to the fact that fundamental particles can incorporate excess 40Ar into their structure when nucleating in restricted to closed systems, such as shales. This excess 40Ar, which represents radiogenic 40Ar released from nearby altered silicates, might be temporarily adsorbed at the surface of the rock pore spaces and is therefore available for incorporation in nucleating and growing particles.

Paleoenvironmental changes in the Black Sea since the LGM were reconstructed using a multi-proxy approach. The hydrology and water chemistry of the Black Sea were significantly influenced by meltwater pulses originated from the Scandinavian Ice Sheet between 15.5 and 18 ka. The subsequent warming during Bölling/Alleröd and Early Holocene led to calcite precipitation, interrupted by the YD cold period. A steady increase in the d18O of Black Sea water was related to a higher d18O of the meteoric precipitation. Diverging d18O trends from different water depths indicate a stratification of the then lacustrine Black Sea. At 9.3 ka the inflow of Mediterranean water started as indicated by a drastic increase in the Mg/Ca and Sr/Ca of ostracod shells. High-frequent fluctuations in the river run-off of the Danube and Sakarya (Anatolia) rivers could be linked to the NAO. The data shows the persistence of the NAO-influence also during deglacial times and on millennial to decadal time scales.

Isotope studies, using 14C dating, δ13C and δ18O measurements, were performed at eight speleothems taken from three submerged caves situated along the eastern Adriatic coast, Croatia. The speleothems were taken from 17 m to 38.5 m depth below mean sea level. The samples consist of four stalagmites and four stalactites in position of growth, covered with marine biogenic overgrowth, and the length of speleothems ranges from ~80 mm to ~190 mm. The youngest (surface) and the oldest (base) layers of speleothems were radiocarbon dated and the 14C ages range from 21,600 cal B.P. to 37,000 yr B.P. During that period the global sea level was more than 40 m below the recent one, so presently submerged objects were under the subaerial conditions necessary for speleothem deposition. 14C ages of the youngest layer range from 21,600 to 32,200 cal B.P. for different submerged speleothems. This indicates the time when the speleothem growth ceased, most probably due to flooding of the cave with either fresh or brackish water. Speleothem growth during the Last Glacial Maximum (30–19 kyr ago) and different time of growth cessation for the different speleothem samples suggest that climate change was not the reason for cessation of deposition. Samples for δ13C and δ18O measurements were taken from six submerged speleothems with sampling distances of ca. 5–10 mm from the surface to the base of speleothems. Most of the δ13C values are in the range from −10.5‰ to −8.5‰, with few exceptions to −6‰. These values are typical for Dinaric karst, and very different values for marine biogenic overgrowth indicate that no isotopic exchange took place during the submerged period. δ18O values range from −6.7‰ to −4.1‰. A weak correlation between δ13C and δ18O values indicates possible kinetic isotope fractionation during the calcite precipitation. If the δ18O record is interpreted as climatic signal, it suggests similar climatic conditions for the late Pleistocene and the Holocene, especially no significant differences in temperature and/or moisture transport.

This study questions the propagation of far field stress and the reactivation of inherited faults in the forelands during an orogeny. The NW-SE hercynian and the NE-SW variscan directions of structures in southcentral France forms the well-known “hercynian V” playing a major role in the subsequent sedimentation and tectonic deformation in the eastern Aquitaine Basin. The most important structures recognized in the area include the N20° Villefranche-Toulouse fault and the N150° West Quercynois Accident. Our study combines structural fieldwork with petrography and geochemical analyses of syn-kinematic calcites to better spatially and temporally characterize the linkages between intraplate deformations, the nature of associated syn-kinematic fluids and major events occurring at the plate boundaries. Fieldwork observations and structural analyses reveal three principal directions: E-W reverse faults, NW-SE dextral and NE-SW sinistral strike-slip faults. Paleostress inversions show that they are kinematically coherent, all with a nearly N-S horizontal . Moreover, evidence of EW normal faulting exists, characterized by a N-S extension. In order to conduct a petrographic and geochemical study, 30 oriented thin sections have been realized from calcite cement samples collected from faults and fractures. Observations of thin-sections with alizarin–potassium ferricyanide and by cathodoluminescence microscopy allows for documentation of the cement stages. The two different stress states (extension and compression) consist of specific cement type: calcite extensive (CAL-E) and calcite compressive (CAL-C). These two fracture fillings are characterized by two distinct geochemical signatures (-6.65 ‰ and -6.02 ‰ in d18O and -3.80 ‰ and -0.24 ‰ in d13C). In situ U-Pb age of syn-kinematic calcite suggest two distinct periods of tectonic activity during the (1) Campanian/Maastrichtian and the (2) Lutetian/Bartonian. Clumped isotope data suggests a crystallization temperature of about 45°C and d18O of paleo fluid around 0‰. Using this combined approach, we revisit the tectonic calendar revealing tectonic events not always clearly expressed in the field. We show that stress fields propagate throughout intraplate settings in the form of pulses of strong tectonic activity from the Pyrenean Orogeny