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1. Palaeoceanographic and hydrodynamic variability for the last 47 kyr in the southern Gulf of Cádiz (Atlantic Moroccan margin): Sedimentary and climatic implications

Author: Thomas Vandorpe, Stanislas Delivet, Dominique Blamart, Claudia Wienberg, Frank Bassinot, Furu Mienis, Jan‐Berend W. Stuut, and David Van Rooij
Subjects: aeolian dust, Antarctic Intermediate Water, Azores Front, bottom currents, cold‐water corals, Pen Duick drift, Geology, QE1-996.5
Abstract: Abstract X‐ray fluorescence, grain‐size and oxygen and carbon stable isotope measurements of a 33 m long piston core, recovered from the Pen Duick drift located at the foot of the prominent Pen Duick Escarpment (Atlantic Moroccan margin), are combined to decipher past oceanographic conditions. The data indicate that, similar to the northern Gulf of Cádiz, the Azores Front exerts a major control on the palaeoclimatology of the region. Contrasting the northern Gulf of Cádiz, where Mediterranean Outflow Water is the main water mass at similar water depths, the palaeoceanography of the studied area is mostly influenced by the amount of Antarctic Intermediate Water advected from the south. The density contrast between the Antarctic Intermediate Water and the overlying North Atlantic Central Water determined the strength of the prevailing internal tides and corresponding high current speeds, which drastically impacted the sedimentary record. The most notable impact is the presence of a 7.8 kyr condensed section (30.5–22.7 ka bp). The formation of the Pen Duick sediment drift was not just controlled by the strength of the bottom currents and the intensity of the internal tides, but also by the amount of (aeolian) sediment supplied to the region. Although variable, drift‐growth phases seem to mainly occur during colder periods of the last glacial, that is Heinrich and Dansgaard‐Oeschger events during Marine Isotope Stage 3 and late Marine Isotope Stage 2. These periods, characterised by increased aeolian dust supply and higher bottom currents, coincide with a phase of prolific cold‐water coral growth and enhanced coral mound formation as recorded in numerous cores obtained from the southern Gulf of Cádiz. This implies that both records (on and off mound cores) are pivotal to provide the complete picture of the palaeoclimatic and palaeoceanographic conditions in the region.
Published: 2023
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2. Reconstructing the thermal history of fish juveniles using stable oxygen isotope analysis of otoliths

Author: Fabien Morat, Dominique Blamart, Bernadette Bounket, Christine Argillier, Georges Carrel, and Anthony Maire
Subjects: water temperature, fractionation equation, European chub, Squalius cephalus, Rhône river, Environmental sciences, GE1-350
Abstract: Introduction: Characterizing the thermal habitat of fish is key to understanding their ecological requirements in order to make appropriate management plans for the preservation of fish populations in the context of climate change. Little is known about the thermal habitat of the early life stages of fish (larvae and juveniles), as most methods have been designed for large, easily handled individuals. In particular, the study of otoliths holds great promise for unveiling the early thermal history of fish, although it is challenging to implement due to the very small size of the biological material.Methods: The stable oxygen isotope content (δ18O) of biogenic carbonates (such as otoliths) can be used to reconstruct the life temperature of fish individuals. However, relationships between δ18O of otoliths and ambient temperature are scarce and mainly developed for commercial species. In this study, we assessed the δ18O of juvenile European chub (Squalius cephalus, Linnaeus 1758) living in a section of the lower Rhône River in France.Results: The δ18O of otoliths showed significant relationship with ambient temperature [δ18Ooto(VPDB)- δ18Ow(VPDB) = 33.391 – 0.2641 * T (°C)], and the relationship between temperature and the fractionation factor (α) was 1,000 ln α = −43.472 + 21.205 [1,000/T(K)].Discussion: As expected, back-calculated temperatures from these equations were in much better agreement with the measured in situ temperatures than previously published equations. This equation is the first to be developed for leuciscid fish in Europe and the second in the world.
Published: 2023
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3. Imprint of Holocene Climate Variability on Cold‐Water Coral Reef Growth at the SW Rockall Trough Margin, NE Atlantic

Author: Lucile Bonneau, Christophe Colin, Edwige Pons‐Branchu, Furu Mienis, Nadine Tisnérat‐Laborde, Dominique Blamart, Mary Elliot, Tim Collart, Norbert Frank, Lorna Foliot, and Eric Douville
Subjects: cold‐water coral mounds, SW Rockall Trough margin, coral occurrence, millennial‐scale climate variations, paleo‐hydrology, Holocene, Geophysics. Cosmic physics, QC801-809, Geology, QE1-996.5
Abstract: Abstract U‐Th ages and temperatures derived from Li/Mg have been measured on coral fragments of Lophelia pertusa and Madrepora oculata collected from two sediment cores, which were taken from cold‐water coral (CWC) mounds at 700–790m water depth at the SW Rockall Trough margin. Our data, combined with previous published data, have allowed us to first estimate the occurrence of CWC at the SW Rockall Trough margin during the Holocene and, second, to better constrain the environmental conditions driving variability in CWC growth. CWC abundance is marked by a pronounced increase in the mid‐Holocene (∼6 ka) and is modulated by millennial‐scale variability throughout the late‐Holocene. The mid‐Holocene proliferation of CWC coincides with lowest IRD abundances and a major reorganization of the circulation at thermocline depth in the Rockall Trough, marked by the progressive replacement of the fresh‐cold Sub‐Arctic Intermediate Water (SAIW) by the saltier and nutrient‐rich Eastern North Atlantic Water (ENAW). This event must have established a modern‐like winter mixed layer and thermocline structure, generating suitable conditions for enhanced surface productivity, downslope transport of food particles, bottom current acceleration at mound depth and thus CWC growth. Several short time intervals of decreased CWC occurrences closely match prominent increases in North Atlantic drift ice and storminess in Northern Europe. We, therefore, propose that high detrital supply and/or changes in the vertical density gradient associated with millennial‐scale ice‐rafted detritus (IRD) events are the likely controlling factors for CWC growth and subsequent mound formation on the SW Rockall Trough margin.
Published: 2018
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4. Surface ocean pH variations since 1689 CE and recent ocean acidification in the tropical South Pacific

Author: Henry C. Wu, Delphine Dissard, Eric Douville, Dominique Blamart, Louise Bordier, Aline Tribollet, Florence Le Cornec, Edwige Pons-Branchu, Arnaud Dapoigny, and Claire E. Lazareth
Subjects: Science
Abstract: Ocean acidification due to the industrial era is a major marine environmental concern, yet little is known on the historical ocean pH changes prior to human influence. Here, Wu et al. show that tropical South Pacific seawater pH is linked to ENSO pacing and has recently been decreasing rapidly.
Published: 2018
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5. Preliminary indication of ontogenetic and spatial variations in the whole otolith isotopic and elemental signatures of Solea solea in the Gulf of Lions (NW Mediterranean)

Author: Fabien Morat, Raymonde Lecomte-Finiger, Dominique Blamart, Michel Robert, and Yves Letourneur
Subjects: flatfish, otolith microchemistry, stable isotope, coastal lagoon, river rhône, Aquaculture. Fisheries. Angling, SH1-691
Abstract: Knowledge of fish life cycles is important for exploited species. In the Mediterranean Sea, catches of common sole (Solea solea) have fluctuated widely since the 1970s. Solea solea displays an ontogenetic shift in habitat: sole larvae are marine, juveniles inhabit shallow marine waters and coastal lagoons and adults inhabit deeper marine waters. Although the results of this study were obtained using only a small set of individuals, the otolith elemental composition and isotopic ratios were investigated for the three life stages (post-larval, juvenile and adult) in order to acquire a better knowledge of the variability in environmental conditions experienced by the common sole at each life stage in the NW Mediterranean. Moreover, this study provides the first evaluation of the potential of whole otolith microchemistry for investigating habitat connectivity in sole populations from the Gulf of Lions. The elemental and isotopic signatures of otoliths of post-larvae captured in various environments appear to show variations related to the River Rhône inputs (high Ba/Ca and low Sr/Ca ratios). Juveniles appear to show significant variations in otolith elemental and isotopic compositions depending not only on the physico-chemical properties of water in the nurseries they inhabit (Rhône River, Thau or Mauguio lagoons), but also as a result of variations in the chemical composition of their surrounding sediments and in their benthic prey. Adults exhibit otolith differences for isotopic ratios only, which is probably linked to the River Rhône inputs. Finally, several significant relationships were observed between otolith elemental composition and fish size in specimens captured at the River Rhône mouth. However, these variations seem to be an indication of the composition acquired in each environment rather than a sign of ontogeny.
Published: 2012
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6. The great melting pot. Common sole population connectivity assessed by otolith and water fingerprints.

Author: Fabien Morat, Yves Letourneur, Jan Dierking, Christophe Pécheyran, Gilles Bareille, Dominique Blamart, and Mireille Harmelin-Vivien
Subjects: Medicine, Science
Abstract: Quantifying the scale and importance of individual dispersion between populations and life stages is a key challenge in marine ecology. The common sole (Solea solea), an important commercial flatfish in the North Sea, Atlantic Ocean and the Mediterranean Sea, has a marine pelagic larval stage, a benthic juvenile stage in coastal nurseries (lagoons, estuaries or shallow marine areas) and a benthic adult stage in deeper marine waters on the continental shelf. To date, the ecological connectivity among these life stages has been little assessed in the Mediterranean. Here, such an assessment is provided for the first time for the Gulf of Lions, NW Mediterranean, based on a dataset on otolith microchemistry and stable isotopic composition as indicators of the water masses inhabited by individual fish. Specifically, otolith Ba/Ca and Sr/Ca profiles, and δ(13)C and δ(18)O values of adults collected in four areas of the Gulf of Lions were compared with those of young-of-the-year collected in different coastal nurseries. Results showed that a high proportion of adults (>46%) were influenced by river inputs during their larval stage. Furthermore Sr/Ca ratios and the otolith length at one year of age revealed that most adults (∼70%) spent their juvenile stage in nurseries with high salinity, whereas the remainder used brackish environments. In total, data were consistent with the use of six nursery types, three with high salinity (marine areas and two types of highly saline lagoons) and three brackish (coastal areas near river mouths, and two types of brackish environments), all of which contributed to the replenishment of adult populations. These finding implicated panmixia in sole population in the Gulf of Lions and claimed for a habitat integrated management of fisheries.
Published: 2014
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7. On the combination of the planktonic foraminiferal Mg/Ca, clumped (Δ47) and conventional (δ18O) stable isotope paleothermometers in palaeoceanographic studies

Author: Marion Peral, Franck Bassinot, Mathieu Daëron, Dominique Blamart, Jérôme Bonnin, Frans Jorissen, Catherine Kissel, Elisabeth Michel, Claire Waelbroeck, Helene Rebaubier, William R Gray, Chemistry, Analytical, Environmental & Geo-Chemistry, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Climat et Magnétisme (CLIMAG), Processus et interactions de fine échelle océanique (PROTEO), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: [SDU]Sciences of the Universe [physics], Geochemistry and Petrology
Abstract: International audience; Assuming that foraminiferal clumped isotope (Δ47) values are independent of seawater salinity and pH, the combination of Mg/Ca, δ18O and Δ47 values, may in theory allow us to disentangle the temperature, salinity/δ18Osw and pH signals. Here, we present a new Mg/Ca-Δ47 dataset for modern planktonic foraminifera, from various oceanographic basins and covering a large range of temperatures (from 0.2 to 25.4 °C). These measurements were performed on the same samples and species as the ones used for the foraminiferal Δ47 calibration of Peral et al. (2018), allowing comparison between both Mg/Ca and Δ47 paleothermometers (excluding the two benthic foraminiferal data points). There is a good agreement between these two paleothermometers when the Mg/Ca-temperature is corrected for seawater salinity and pH, suggesting that foraminiferal Δ47 may not be influenced by salinity or pH. However, our results show that Δ47 temperature uncertainties still limit our ability to reconstruct pH and δ18Osw from the combination of Mg/Ca, δ18O and Δ47 in a useful manner. We also find that disagreements between Mg/Ca and Δ47 values in G. bulloides persist after correction for vital, salinity and pH effects, suggesting that other process(es) may also influence Mg/Ca in this species. This study also provides an updated I-CDES version of the previously published planktonic and benthic foraminiferal Δ47 calibration of Peral et al. (2018), covering a range of temperature from -2 to 25.4 °C.
Published: 2022
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8. Sea surface temperatures, salinity and pH reconstructions over the last 1,2 Ma in South Indian Ocean using the unique combination of Mg/Ca, d18O and ∆47 in planktonic foraminifera

Author: Dominique Blamart, Thibaut Caley, Thomas Extier, Gulay Isguder, Franck Bassinot, Erin L McClymont, Mathieu Daëron, Marion Peral, and Bruno Malaizé
Subjects: Foraminifera, Salinity, Indian ocean, Oceanography, biology, Plankton, biology.organism_classification, Geology
Abstract: The Mid-Pleistocene transition (MPT) took place between 1,200 Ma and 800 ka (still debated). During this transition, the Earth’s orbitally paced ice age cycles intensified, lengthened from ∼40 000 (∼40 ky) to ∼100 ky, and became distinctly asymmetrical while Earth’s orbital variations remained unchanged. Although orbital variations constitute the first order forcing on glacial-interglacial oscillations of the late Quaternary, they cannot explain alone the shifts in climatic periodicity and amplitude observed during the MPT. In order to explain the MPT, long-term evolution of internal mechanisms and feedbacks have been called upon, in relation with the global cooling trend initiated during the Cenozoic, the expansion of Antarctic and Greenland Ice Sheet and/or the long-term decline in greenhouse gases (particularly CO2). A key point is therefore to accurately reconstruction of oceanic temperatures to decipher the processes driving climate variations.In the present work, we studied the marine sediment core MD96-2048 taken from south Indian Ocean (26*10’482’’ S, 34*01’148’’ E) in the region of the Agulhas current. We compared 5 paleothermometers: alkenone, TEX86, foraminiferal- transfer function, Mg/Ca and clumped isotope. Among these approaches, carbonate clumped-isotope thermometry (∆47) only depends on crystallization temperature, and the ∆47 relationship with planktonic foraminifer calcification temperature is well defined. Since Mg/Ca is not only controlled by temperature but is also affected by salinity and pH. The classical d18O in planktic is dependent on SST and d18Osw, which is regionally correlated with the salinity in the present-day ocean. Assuming that the present-day d18Osw-salinity relation was the same during the MPT, we are able to separate changes in d18Osw from temperature effects and reconstruct past salinity. Combining d18O, Mg/Ca and ∆47 on planktonic foraminifera allow in theory to reconstruct SST, SSS and pH.Here, we measured d18O, Mg/Ca and ∆47 on the shallow-dwelling planktonic species Globigerinioides ruber ss. at the maximal of glacial and interglacial periods over the last 1.2 Ma. Our set of data makes it possible to estimate the long-term evolution of SST, salinity and pH (and thus have an insight into the atmospheric CO2 concentration) across the MPT. Frist, strong differences are observed between the 5 derived-SST: the alkenone and TEX86 recorded the higher temperatures than the other SST proxies. Alkenone derived-SST do not show glacial-interglacial variations within the MPT. The Mg/Ca and transfer function derived-SST show a good agreement each other, while the clumped-isotope derived-SST are systematically colder than the other derived-SST. Then, our ∆47-SST, salinity and pH results clearly show that amplitude of glacial-interglacial variations was insignificant between 1.2 and 0.8 Ma (within the MPT) and increased after the MPT. Finally, we also discussed the potential to use this unique combination of proxies to reconstruct changes of atmospheric CO2 concentration.
Published: 2021
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9. The contribution of the foraminiferal Mg/Ca ratio, clumped and conventional stable isotope paleothermometers combination for palaeoceanographic studies

Author: Catherine Kissel, Marion Peral, Mathieu Daëron, Elisabeth Michel, Frans Jorissen, Dominique Blamart, Franck Bassinot, Claire Waelbroeck, William R Gray, Hélène Rebaubier, and Jérôme Bonnin
Subjects: Chemistry, Stable isotope ratio, Environmental chemistry
Published: 2021
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10. Changes in temperature and oxygen isotopic composition of Mediterranean water during the Mid-Pleistocene transition in the Montalbano Jonico section (southern Italy) using the clumped-isotope thermometer

Author: Dominique Blamart, Mathieu Daëron, Sébastien Nomade, Angela Girone, Marion Peral, Franck Bassinot, Maria Marino, Patrizia Maiorano, Helene Rebaubier, Neri Ciaranfi, Fabien Dewilde, Analytical, Environmental & Geo-Chemistry, Chemistry, Paléocéanographie (PALEOCEAN), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Bari Aldo Moro = University of Bari Aldo Moro (UNIBA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and University of Bari Aldo Moro (UNIBA)
Subjects: Mediterranean climate, 010506 paleontology, δ18O, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Mg/Ca, Paleothermometer, Mediterranean sea, Paleoceanography, paleothermometry, MIS 31, stable isotope, 14. Life underwater, Glacial period, MIS 19, Ecology, Evolution, Behavior and Systematics, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Earth-Surface Processes, foraminifera, Paleontology, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Interglacial, Seawater, Thermocline, Geology
Abstract: International audience; Taking advantage of the recent clumped-isotope methodological developments, the present study focuses on the reconstruction of temperatures and seawater δ18O in the central Mediterranean Sea across the Mid-Pleistocene section from Montalbano Jonico (south of Italy). Our results suggest that Mg/Ca paleothermometer can be biased over several intervals, making clumped-isotope a promising choice to reconstruct past changes in seawater temperature and isotopic composition in the Mediterranean Sea. Our results provide the first clumped-isotope temperature and δ18OSW reconstruction across several glacial and interglacial Marine Isotope Stages from MIS 36 to MIS 19 in the central Mediterranean Sea.During the climatic optimums of MIS 31 and MIS 19, considered as close analogues to the current interglacial in terms of insolation forcing, reconstructed average sub-surface temperatures from benthic foraminifer analyses (13.8 ± 1.5 °C and 14.8 ± 1.3 °C, respectively) and isotopic composition of seawater (between 1.6 ± 0.4‰ and 2.0 ± 0.3‰) are similar to the ones measured today below the thermocline in the Gulf of Taranto. Our results show that bottom water conditions remained similar in all the studied glacial periods, with cold temperatures around ~ 8 °C in average. The lack of a clear cooling across the Mid-Pleistocene either suggest that glacial oceanographic conditions in the Mediterranean Sea remained relatively stable between the 41 ka-world and the 100 ka-world or that the tectonic uplift that took place during this transition balanced out the MPT cooling trend through the shallowing of the deposition site.
Published: 2020
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11. Characterizing the Eemian-Weichselian transition in northwestern Europe with three multiproxy speleothem archives from the Belgian Han-sur-Lesse and Remouchamps cave systems

Author: Stef Vansteenberge, Camille Ek, Yves Quinif, Dominique Blamart, David P. Gillikin, Florent Hodel, Stijn Van Malderen, Hai Cheng, Dominique Genty, R. Lawrence Edwards, Sophie Verheyden, Frank Vanhaecke, Steven Goderis, Philippe Claeys, Analytical, Environmental & Geo-Chemistry, Chemistry, Earth System Sciences, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Paléocéanographie (PALEOCEAN)
Subjects: 010506 paleontology, Archeology, geology, 010504 meteorology & atmospheric sciences, Speleothem, Western Europe, 01 natural sciences, Interglacial(s), Cave, Paleoclimatology, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Stable isotopes, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, Eemian, Global and Planetary Change, geography.geographical_feature_category, archaeology, 15. Life on land, Glacial inception, Speleothems, 13. Climate action, Interglacial, Sedimentary rock, Physical geography, Quaternary, Geology
Abstract: Interglacial to glacial transitions represent the most drastic turnovers in the Quaternary climate system. Yet, millennial-scaled climate variability and stochastic internal variability that result in (inter)glacial transitions remain poorly understood. Here, three speleothems from two different cave systems in Belgium are investigated to characterize the Eemian to early Weichselian transition. The speleothems show high reproducibility for δ13C, interpreted as a proxy for past vegetation activity, controlled by type of vegetation above the cave. All three speleothems show a drastic increase in δ13C between 118 and 117 ka, reflecting a rapid change in vegetation from last interglacial temperate tree species towards glacial open-grass vegetation. This transition shows a strong affinity with the Late Eemian Aridity Pulse (LEAP) at 118 ± 1 ka, previously identified in pollen records from Western Germany. An age of 117.7 ± 0.5 ka is determined for the start of this transition in the Belgian speleothems. The speleothem records show a distinct transition in the proxies between Eemian optimum conditions and increased variability during the glacial inception and therefore the Eemian-Weichselian transition is set at 117.7 ± 0.5 ka in the speleothem records. High-resolution trace element analysis shows that the transition is initiated by a cooling pulse followed by a decrease in precipitation. Through comparison with other archives, including North-Atlantic sedimentary records, it is proposed that the transition at 117.7 ka constitutes an internal climate response caused by a substantial input of freshwater from degraded ice-sheets by the end of the Eemian (∼120-118 ka).
Published: 2019
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12. Reconstruction of the formation history of the Darwin Mounds, N Rockall Trough: How the dynamics of a sandy contourite affected cold-water coral growth

Author: Lissette Victorero, Veerle A.I. Huvenne, Dominique Blamart, Edwige Pons-Branchu, Mark Mavrogordato, Ocean and Earth Science [Southampton], University of Southampton-National Oceanography Centre (NOC), Paléocéanographie (PALEOCEAN), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Géochrononologie Traceurs Archéométrie (GEOTRAC), University of Southampton, National Oceanography Centre [Southampton] (NOC), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Water mass, 010504 meteorology & atmospheric sciences, Coral, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, law.invention, Paleontology, Lophelia, Darwin Mounds, Continental margin, Geochemistry and Petrology, Ocean gyre, law, North-east Atlantic, 14. Life underwater, Radiocarbon dating, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Holocene, 0105 earth and related environmental sciences, Cold-water coral mounds, geography, geography.geographical_feature_category, biology, Geology, Contourite, CT-scan, biology.organism_classification, Lophelia pertusa
Abstract: International audience; Cold-water coral mounds, formed through a feed-back process of cold-water coral growth and sediment baffling, have been studied all along the NE Atlantic continental margin. However, major questions remain concerning their formation history, especially their initiation and early development in relation to the surrounding sediment dynamics. For the first time, two small mounds located in a sandy contourite have been cored from the top to mound base: here, the formation history of the Darwin Mounds, located in the Northern Rockall Trough was investigated and reconstructed from two piston cores using a multidisciplinary approach. This consisted of CT-scanning for quantifying coral density changes with depth, grain-size analysis to obtain the hydrodynamic trends and radiocarbon and U-series dating to place the results into a wider paleoceanographic context. The results show that the Darwin Mounds formed during the early Holocene (~ 10 ka BP) through sediment baffling, mainly by Lophelia pertusa. The initiation of both mounds shows a similar pattern of increased current velocities resulting in coarser sediment deposition and a relatively high coral density with a peak of 23 vol%. The mound growth was rapid between ~ 10–9.7 ka BP (up to 277 cm ka− 1 in one of the mounds), with further vibrant growth periods around ~ 8.8 ka BP, 6.5 ka BP and 3.4 ka BP. The demise of the mounds ca. ~ 3 ka BP was likely caused by an intensification in bottom current velocities causing a hostile environment for coral growth in the contourite setting. In a wider context, the development of the Darwin Mounds appears to have responded to the relative strength and position of the Subpolar Gyre, which affected food supply to the corals, sedimentation rates, current speeds and other water mass properties in the area.
Published: 2016
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13. South Atlantic intermediate water advances into the North-east Atlantic with reduced Atlantic meridional overturning circulation during the last glacial period

Author: Dierk Hebbeln, Freya Hemsing, Jean-Carlos Montero-Serrano, Christophe Colin, David Van Rooij, Dominique Blamart, Anne-Marie Wefing, Quentin Dubois-Dauphin, Norbert Frank, Lucile Bonneau, Edwige Pons-Branchu, and Paolo Montagna
Subjects: Water mass, Antarctic Intermediate Water, 010504 meteorology & atmospheric sciences, North Atlantic Deep Water, 010502 geochemistry & geophysics, 01 natural sciences, Geophysics, Oceanography, Mediterranean sea, 13. Climate action, Geochemistry and Petrology, Thermohaline circulation, 14. Life underwater, Glacial period, Thermocline, Geology, Holocene, 0105 earth and related environmental sciences
Abstract: The Nd isotopic composition (eNd) of seawater and cold-water coral (CWC) samples from the Gulf of Cadiz and the Alboran Sea, at a depth of 280–827 m were investigated in order to constrain middepth water mass dynamics within the Gulf of Cadiz over the past 40 ka. eNd of glacial and Holocene CWC from the Alboran Sea and the northern Gulf of Cadiz reveals relatively constant values (−8.6 to −9.0 and −9.5 to −10.4, respectively). Such values are similar to those of the surrounding present-day middepth waters from the Mediterranean Outflow Water (MOW; eNd ∼ −9.4) and Mediterranean Sea Water (MSW; eNd ∼ −9.9). In contrast, glacial eNd values for CWC collected at thermocline depth (550–827 m) in the southern Gulf of Cadiz display a higher average value (−8.9 ± 0.4) compared to the present-day value (−11.7 ± 0.3). This implies a higher relative contribution of water masses of Mediterranean (MSW) or South Atlantic origin (East Antarctic Intermediate Water, EAAIW). Our study has produced the first evidence of significant radiogenic eNd values (∼ −8) at 19, 23–24, and 27 ka, which are coeval with increasing iceberg discharges and a weakening of Atlantic Meridional Overturning Circulation (AMOC). Since MOW eNd values remained stable during the last glacial period, it is suggested that these radiogenic eNd values most likely reflect an enhanced northward propagation of glacial EAAIW into the eastern Atlantic Basin.
Published: 2016
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14. Development of laser ablation multi-collector inductively coupled plasma mass spectrometry for boron isotopic measurement in marine biocarbonates: new improvements and application to a modern Porites coral

Author: Caroline Assailly, Claire E. Lazareth, François Thil, John Butsher, Eric Douville, Thierry Leblanc, and Dominique Blamart
Subjects: Laser ablation, 010504 meteorology & atmospheric sciences, biology, Chemistry, Organic Chemistry, Porites, Analytical chemistry, Mineralogy, chemistry.chemical_element, Isotopes of boron, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Silicate, Analytical Chemistry, chemistry.chemical_compound, Impact crater, Seawater, 14. Life underwater, Boron, Inductively coupled plasma mass spectrometry, Spectroscopy, 0105 earth and related environmental sciences
Abstract: Rationale Laser Ablation coupled to Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICPMS) is a powerful tool for the high-precision measurement of the isotopic ratios of many elements in geological samples, with the isotope ratio ((11) B/(10) B) of boron being used as an indicator of the pH of oceanic waters. Most geological samples or standards are polished and ablation occurs on flat surfaces. However, the shape and the irregularities of marine biocarbonates (e.g., corals, foraminifera) can make precise isotopic measurements of boron difficult. Even after polishing, the porosity properties and the presence of holes or micro-fractures affect the signal and the isotopic ratio when ablating the material, especially in raster mode. Methods The effect of porosity and of the crater itself on the (11) B signal and the isotopic ratio acquired by LA-MC-ICPMS in both raster and spot mode was studied. Characterization of the craters was then performed with an optical profilometer to determine their shapes and depths. Surface state effects were examined by analyzing the isotopic fractionation of boron in silicate (NIST-SRM 612 and 610 standards) and in carbonate (corals). Results Surface irregularities led to a considerable loss of signal when the crater depth exceeded 20 µm. The stability and precision were degraded when ablation occurred in a deep cavity. The effect of laser focusing and of blank correction was also highlighted and our observations indicate that the accuracy of the boron isotopic ratio does not depend on the shape of the surface. After validation of the analytical protocol for boron isotopes, a raster application on a Porites coral, which grew for 18 months in an aquarium after field sampling, was carried out. Conclusions This original LA-MC-ICPMS study revealed a well-marked boron isotope ratio temporal variability, probably related to growth rate and density changes, irrespective of the pH of the surrounding seawater. Copyright © 2015 John Wiley & Sons, Ltd.
Published: 2015
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15. Reservoir Ages in the Western Tropical North Atlantic from One Coral off Martinique Island (Lesser Antilles)

Author: Eric Douville, Elsa Cortijo, Dominique Blamart, Lucile Bonneau, Edwige Pons-Branchu, Martine Paterne, Nathalie Feuillet, Christophe Colin, Jennifer Weill-Accardo, Guy Cabioch, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), CNRS - ORSTOM Paléohydrologie, Paléoclimatique Continentales, Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU), Paléocéanographie (PALEOCEAN), Nanyang Technological University [Singapour], Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Universität Heidelberg [Heidelberg], Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Universität Heidelberg [Heidelberg] = Heidelberg University, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] ( LSCE ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), Institut de Physique du Globe de Paris ( IPGP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -IPG PARIS-Université Paris Diderot - Paris 7 ( UPD7 ) -Université de la Réunion ( UR ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques ( LOCEAN ), Muséum National d'Histoire Naturelle ( MNHN ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Centre National de la Recherche Scientifique ( CNRS ), Centre de Recherches Pétrographiques et Géochimiques ( CRPG ), Université de Lorraine ( UL ) -Centre National de la Recherche Scientifique ( CNRS ), Institut des Sciences de la Terre de Paris ( iSTeP ), and Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS )
Subjects: [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, 010506 paleontology, Archeology, Lesser Antilles, 010504 meteorology & atmospheric sciences, δ18O, Coral, location.country, stable isotopes, 01 natural sciences, law.invention, volcanic effects, location, marine reservoir ages, law, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Martinique, 14. Life underwater, Radiocarbon dating, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, coral, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, biology, Volcanic arc, biology.organism_classification, Oceanography, Volcano, 13. Climate action, Martinique island, General Earth and Planetary Sciences, Siderastrea siderea, Geology
Abstract: Sea surface reservoir ages (R) are reported from radiocarbon (14C) measurements of the annual growth bands of coral Siderastrea siderea collected on the Atlantic coast off Martinique Island, in the Lesser Antilles volcanic arc. Mean values of R are similar between 1835 and 1845 during pre-anthropogenic times at 385±30 yr and between 1895 and 1905 at 382±20 yr when there was a huge eruption from the Montagne Pelée volcano in 1902–1903. Limited 14C aging of sea surface (~40 yr) may be due to enhanced volcanic activity. Variability of R is slightly greater during 1835–1845 than during 1895–1905. It is linked to a moderate increase of ∆14C of 5‰, strengthened by a clear increase of δ18O of 0.4‰. This is attributed to a decrease of the northward advection of the South Atlantic Waters into the western tropical North Atlantic and Caribbean Sea and relative enhanced westward flux of the tropical North Atlantic surface waters, the southern waters having lower values of 14C and δ18O than the North Atlantic ones. From 1835 to 1845, the fraction of the South Atlantic Waters transported up to Martinique Island was reduced from 25% to 15%.
Published: 2018
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16. Possible controls on Li, Na, and Mg incorporation into aragonite coral skeletons

Author: Claire Rollion-Bard, Dominique Blamart, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, biology, Precipitation (chemistry), Chemistry, Aragonite, Coral, Analytical chemistry, Mineralogy, Geology, Crystal structure, engineering.material, biology.organism_classification, Ion, Partition coefficient, Lophelia, Geochemistry and Petrology, engineering, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Rayleigh fractionation, ComputingMilieux_MISCELLANEOUS
Abstract: We present ion probe measurements of Li/Ca, Na/Ca and Mg/Ca ratios of three scleractinian corals (Lophelia pertusa, Desmophyllum cristagalli, Porites lutea). These ratios are systematically enriched in Rapid Accretion Deposits (RADs) compared to surrounding fibres, or Thickening Deposits (TDs), and present huge variations that cannot be ascribed to any environmental parameter change. Moreover, these elemental ratios are positively correlated in the three coral species. We explore different mechanisms to explain these observations: (1) mixing between different carrier phases, (2) influence of specific ion pumps, (3) precipitation rate effects, (4) Rayleigh fractionation, and (5) pH change in the calcifying fluid. Of these possibilities, the most likely proposal seems to be kinetic effects that have influence on the number of defects (i.e., modification of the crystallographic structure), which are linked to the precipitation rate of the skeleton, and the partition coefficients are the cause of the positive correlation between Li, Na, and Mg in the coral skeleton. Temperature has an indirect influence on the skeletal concentration of these elements through its effect on the skeletal growth rate.
Published: 2015
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17. Questioning the accuracy of K-Ar ages: example of the dating of two trachytic domes from the Gölcük (Turkey)

Author: Dominique Blamart, Vincent Scao, Sébastien Nomade, Bernard Platevoet, Hervé Guillou, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Géosciences Paris Sud (GEOPS), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Excès d’argon, Turkey, Excès d'argon, Gölcük volcano, 40 Ar/ 39 Ar, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, K-Ar, Turquie, Geology, volcan de Gölcük, Turquie Keywords : K-Ar, 010502 geochemistry & geophysics, 01 natural sciences, 40Ar/39Ar, Pleistocene, Mots-clés : K-Ar, [SDU]Sciences of the Universe [physics], Excess Argon, Pléistocène, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: International audience; Le Gölcük, situé au sud de la ville d'Isparta (Turquie), est un volcan composite, construit en trois phases durant le Pléistocène (Alici et al., 1998 ; Platevoet et al., 2008 ; Elitok et al., 2010). Les études réalisées par Platevoet et al. (2008) et Schmitt et al. (2014) se sont intéressées en partie à la datation de deux dômes mis en place au sein de la caldeira du Gölcük. Les âges K-Ar (Platevoet et al., 2008) de ces dômes trachytiques (Küçükçesme Tepe : 52 ± 2 ka et Pilav Tepe : 24 ± 2 ka) sont significativement plus vieux que les âges (U-Th)/He sur zircons obtenus par Schmitt et al. (2014) étant respectivement de 14,1 ± 0,5 et de 12,9 ± 0,4 ka. Nous avons testé l'hypothèse proposée par Schmitt et al. (2014) qui est celle d'un excès d' 40 Ar * faussant les âges K-Ar en datant ces mêmes trachytes par la méthode 40 Ar/ 39 Ar. Nos âges 40 Ar/ 39 Ar sur mésostase confirment les âges (U-TH)/He sur zircons et datent l'activité magmatique la plus récente du Gölcük à 13,4 ± 0,3 ka. Nous proposons que l'erreur sur les âges K-Ar soit liée à un excès d'argon probablement porté par des clinopyroxènes associés à la mésostase. ABSTRACT QUESTIONING THE ACCURACY OF K-AR AGES: EXAMPLE OF THE DATING OF TWO TRACHYTIC DOMES FROM THE GÖLCÜK (TURKEY) The Gölcük volcano, located south to the city of Isparta (Turkey), built-up in three stages during the Pleistocene (Alici et al., 1998; Platevoet et al., 2008; Elitok et al., 2010). A reliable and accurate dating of the most recent volcanic stage is crucial to assess the potential hazards for the infrastructures and the populations. In this context, Platevoet et al. (2008) and Schmitt et al. (2014) applied respectively the K-Ar and the (U-Th)/He methods to date the youngest volcanic stage of the Gölcük and obtained contrasted results. Based on the K-Ar dating of two trachytic domes (Kücükcesme Tepe et Pilav Tepe), the post-caldera stage is dated between 52 ± 2 ka and 24 ± 2 ka by Platevoet et al. (2008). When the (U-Th)/He method is applied on zircons from the same trachytic domes, Schmitt et al. (2014) date the post-caldera stage around 14.1 ± 0.5-12.9 ± 0.4 ka. Schmitt et al. (2014) proposed that the K-Ar ages were erroneously too old, probably because of excess 40 Ar*. We have tested this hypothesis by dating groundmass splits of these trachytes using the 40 Ar/ 39 Ar method. Our 40 Ar/ 39 Ar ages reproduce the (U-Th)/He ages on zircons and date the youngest volcanic stage of the Gölcük at 13.4 ± 0.3 ka. Confirming the hypothesis of Schmitt et al. (2014), we propose that the error on the K-Ar ages is related to excess argon probably trapped in small fragments of clinopyroxene attached to the groundmass.
Published: 2017
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18. Geochemical transect through a travertine mount: A detailed record of CO 2 -enriched fluid leakage from Late Pleistocene to present-day – Little Grand Wash fault (Utah, USA)

Author: Dominique Blamart, Bruno Hamelin, Emanuelle Frery, Nadine Ellouz-Zimmerman, Jean-Pierre Gratier, Pierre Deschamps, Rudy Swennen, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), IFP Energies nouvelles (IFPEN), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Geology Section, Department of Earth and Environmental Sciences, K.U.Leuven (KU Leuven), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Travertine, geography, Oxygen and carbon stable isotopes, geography.geographical_feature_category, Vein growth rate, 010504 meteorology & atmospheric sciences, Pleistocene, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Context (language use), Aquifer, Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, CO2-enriched fluids, Paleontology, Meteoric water, Period (geology), Glacial period, Quaternary, Leakage, U/Th dating, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, Geology, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: © 2016 Elsevier Ltd and INQUA Active and fossil endogenic travertine mounts scattered along the Little Grand Wash fault are studied as records of Quaternary CO2-enriched fluid leakage. This study focusses on a particular area where a fossil mount formed in a near-surface setting by successive circulation/sealing episodes from Late Pleistocene to Mid-Holocene and where a modern surface travertine is still being formed by a CO2-enriched fluid source. The fossil mount is composed of horizontal and vertical veins whereby the vertical veins recorded numerous cycles of circulation/sealing/dissolution events and were used as conduits for the CO2-enriched fluid circulation from the depth to the surface or along sub-horizontal fractures where successive precipitation events are recorded. The modern travertine is being built at the surface by successive eruption of Crystal Geyser, an anthropic geyser active since the 1930's. δ13C and δ18O signatures and U/Th datings, ranging from 11.5 ky till present-day allows calibrating in detail the CO2 enriched fluid leakage along a single fault segment and in a post glacial context, as last glaciations in the study area took place 15 ky ago. The dataset shows a high decrease of the oxygen stable isotope values till about 6 ky, then the variations reflect a constant range until present-day. This tends to restrain the period of local increase of the meteoric water input in the aquifer that is sourcing the CO2-enriched water. The fossil travertine represents a 7 ky-long record of CO2 leakage above a natural reservoir, from Late Pleistocene to Mid-Holocene. The flux of CO2 leakage through time and the total escaping volume have been computed and appears to be low in comparison with an anthropogenic leak provoked, for instance, by a non-sealed well. ispartof: Quaternary International vol:437 pages:98-106 status: published
Published: 2017
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19. Supplementary material to 'Transfer of environmental signals from surface to the underground at Ascunsă Cave, Romania'

Author: Virgil Drăgușin, Sorin Balan, Dominique Blamart, Ferenc L. Forray, Constantin Marin, Ionuț Mirea, Viorica Nagavciuc, Aurel Perșoiu, Laura Tîrlă, Alin Tudorache, and Marius Vlaicu
Published: 2017
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20. Transfer of environmental signals from surface to the underground at Ascunsă Cave, Romania

Author: Virgil Drăgușin, Sorin Balan, Dominique Blamart, Ferenc L. Forray, Constantin Marin, Ionuț Mirea, Viorica Nagavciuc, Aurel Perșoiu, Laura Tîrlă, Alin Tudorache, and Marius Vlaicu
Abstract: We present here the results of a four year environmental monitoring program at Ascunsă Cave, Romania, intended to understand how climate information is transferred through the karst system and archived in speleothems. The air temperature inside the cave is around 7 °C, with slight differences between the upper and lower parts of the main passage. Relative humidity measurements were hampered by condensation on the capacitive sensors we used, thus we consider it to be close to 100 %. The local meteoric water line (δ2H = 7.7 δ18O + 10.1), constructed using monthly aggregated rainfall samples, is similar to the global one, revealing the Atlantic as the strongly dominant vapor source. The δ2H excess values, as high as 17 ‰, indicate that precipitation has an important evaporative component, possibly given by moisture recycling over the European continent. CO2 concentrations in cave air have a seasonal signal, with summer minima and winter maxima. This might be indicative of an organic matter reservoir deep within the epikarst that continues to decompose over the winter, possibly modulated by seasonal differences in cave ventilation. The maximum values of CO2 show a rise after the summer of 2014, from around 2000 ppm to about 3500 ppm. An analogous rise is seen in drip water stable isotopes and chemical elements such as Sr and Mg. The variability of stable isotopes and chemical elements is similar at all points inside the cave, indicating that they are draining a homogenous reservoir. Using two newly designed types of water/air equilibrators we were able to determine drip water dissolved CO2, by measuring its concentration in the equilibrator headspace and then using Henry's law to calculate its concentration in water. This opens the possibility of continuous data logging using infrared technology without the need of costly and less reliable chemical determinations.
Published: 2017
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21. Middle to Late Pleistocene activity of the northern Matese fault system (southern Apennines, Italy)

Author: Paolo Galli (a, Biagio Giaccio (b), Paolo Messina (b), Edoardo Peronace (b, Vincenzo Amato (d), Giuseppe Naso (a), Sebastian Nomade (e), Alison Pereira (e, Sabatino Piscitelli (g), Jessica Bellanova (g), Andrea Billi (b), Dominique Blamart (e), Antonio Galderisi (h), Alessandro Giocoli (i), Tony Stabile (g), Francoise Thil (e), Giocoli, A., Consiglio Nazionale delle Ricerche [Roma] (CNR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Università degli Studi del Molise (Unimol), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Istituto di Metodologie per l'Analisi Ambientale (IMAA), Consiglio Nazionale delle Ricerche [Potenza] (CNR), Università degli studi di Napoli Federico II, ENEA - Casaccia, Roma, Géochrononologie Traceurs Archéométrie (GEOTRAC), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), École normale supérieure - Paris (ENS-PSL), Università degli Studi del Molise = University of Molise (UNIMOL), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and University of Naples Federico II = Università degli studi di Napoli Federico II
Subjects: earth-surface processes, Apennine, 40Ar/39Ar dating, active tectonics, Apennines, earthquakes, Late Pleistocene, Middle Pleistocene, paleoseismology, geophysics, Earthquake, 010504 meteorology & atmospheric sciences, Pleistocene, Outcrop, Paleoseismology, Slip (materials science), Structural basin, 010502 geochemistry & geophysics, 01 natural sciences, Active tectonic, Paleoseismologys, Apenninesesocene, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Tephra, ComputingMilieux_MISCELLANEOUS, Holocene, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Earthquakes, Active tectonics, Earthquakesocene, Tectonics, 13. Climate action, Seismology, Geology
Abstract: An integrated investigation including geological, geomorphological, geophysical and structural survey, tephra analyses, 14C and 40Ar/39Ar dating, as well as paleoseismic trenching along the N-Matese fault system is presented. The study allowed the characterization of the tectonic mobility of this structure as well as the associated Bojano basin sedimentary-tectonic evolution since the early Middle Pleistocene, providing also new clues concerning the fault historical activity and the associated Mw > 6.5 earthquakes. We have found lines of evidence for > 1 mm/yr slip rate along the presently buried Bojano fault during the mid Middle Pleistocene, and similar rates for the main fault segments paralleling the Matese flanks. The buried Bojano fault significantly slowed down during the last 300 kyr, ceasing its activity before the Holocene. In turn, the segments outcropping along the Matese flanks reactivated at the onset of Late Pleistocene, after a long period of quiescence (480–110 ka), with robust slip rates that would seem even accelerating in post LGM times. Paleoseismic data suggest the occurrence of four Mw > 6.6 earthquakes in the past 3 ka, three of which match the little known 280 BC event, and the devastating 1456 and 1805 earthquakes. © 2017 Elsevier B.V.
Published: 2017
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22. SIMS method and examples of applications in coral biomineralization

Author: Claire Rollion-Bard, Dominique Blamart, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Elaine DiMasi, Laurie B. Gower, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Chemistry, Coral, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Nanotechnology, 010502 geochemistry & geophysics, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Biomineralization
Abstract: International audience
Published: 2017
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23. Unique authigenic mineral assemblages reveal different diagenetic histories in two neighbouring cold-water coral mounds on Pen Duick Escarpment, Gulf of Cadiz

Author: Laura Mariana Wehrmann, David Van Rooij, J.P. Henriet, Hans Pirlet, Lies De Mol, Philippe Duyck, Veerle Cnudde, Jan Dewanckele, Benjamin Brunner, Dominique Blamart, Anneleen Foubert, and Rudy Swennen
Subjects: Calcite, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Stratigraphy, Aragonite, Geology, Escarpment, Authigenic, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Diagenesis, Petrography, Paleontology, chemistry.chemical_compound, chemistry, engineering, Sedimentary rock, 0105 earth and related environmental sciences, Mud volcano
Abstract: Alpha Mound and Beta Mound are two cold-water coral mounds, located on the Pen Duick Escarpment in the Gulf of Cadiz amidst the El Arraiche mud volcano ﬁeld where focused ﬂuid seepage occurs. Despite the proximity of Alpha Mound and Beta Mound, both mounds differ in their assemblage of authigenic minerals. Alpha Mound features dolomite, framboidal pyrite and gypsum, whereas Beta Mound contains a barite layer and predominantly euhedral pyrite. The diagenetic alteration of the sedimentary record of both mounds is strongly inﬂuenced by biogeochemical processes occurring at shallow sulphate methane transition zones. The combined sedimentological, petrographic and isotopic analyses of early diagenetic features in gravity cores from Alpha Mound and Beta Mound indicate that the contrast in mineral assemblages between these mounds is caused by differences in ﬂuid and methane ﬂuxes. Alpha Mound appears to be affected by strong ﬂuctuations in the ﬂuid ﬂow, causing shifts in redox boundaries, whereas Beta Mound seems to be a less dynamic system. To a large extent, the diagenetic egimes within cold-water coral mounds on the Pen Duick Escarpment appear to be controlled by ﬂuid and methane ﬂuxes deriving from layers underlying the mounds and forcings like pressure gradients caused by bottom current. However, it also becomes evident that authigenic mineral assemblages are not only very sensitive recorders of the diagenetic history of speciﬁc cold-water coral mounds, but also affect diagenetic processes in turn. Dissolution of aragonite, lithiﬁcation by precipitation of authigenic minerals and subsequent brecciation of these lithiﬁed layers may also exert a control on the advective and diffusive ﬂuid ﬂow within these mounds, providing a feedback mechanism on subsequent diagenetic processes.
Published: 2011
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24. 13C18O clumping in speleothems: Observations from natural caves and precipitation experiments

Author: John M. Eiler, Dominique Blamart, Richard Maire, Russell N. Drysdale, Dominique Genty, Giovanni Zanchetta, Karine Wainer, Weifu Guo, M. Daëron, Ronny Boch, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), California Institute of Technology (CALTECH), Geophysical Laboratory [Carnegie Institution], Carnegie Institution for Science [Washington], University of Innsbruck, University of Melbourne, Aménagement, Développement, Environnement, Santé et Sociétés (ADES), Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Bordeaux Montaigne, University of Pisa - Università di Pisa, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Carnegie Institution for Science, Leopold Franzens Universität Innsbruck - University of Innsbruck, and Université Bordeaux Segalen - Bordeaux 2-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Calcite, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Carbonate minerals, Geochemistry, Mineralogy, Speleothem, Stalagmite, 010502 geochemistry & geophysics, 01 natural sciences, Isotopes of oxygen, chemistry.chemical_compound, Isotope fractionation, chemistry, Cave, 13. Climate action, Geochemistry and Petrology, Carbonate, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, Geology, 0105 earth and related environmental sciences
Abstract: The oxygen isotope composition of speleothems is an important proxy of continental paleoenvironments, because of its sensitivity to variations in cave temperature and drip water δ^(18)O. Interpreting speleothem δ^(18)O records in terms of absolute paleotemperatures and δ^(18)O values of paleo-precipitation requires quantitative separation of the effects of these two parameters, and correcting for possible kinetic isotope fractionation associated with precipitation of calcite out of thermodynamic equilibrium. Carbonate clumped-isotope thermometry, based on measurements of Δ_47 (a geochemical variable reflecting the statistical overabundance of ^(13)C^(18)O bonds in CO_2 evolved from phosphoric acid digestion of carbonate minerals), potentially provides a method for absolute speleothem paleotemperature reconstructions independent of drip water composition. Application of this new technique to karst records is currently limited by the scarcity of published clumped-isotope studies of modern speleothems. The only modern stalagmite reported so far in the literature yielded a lower Δ_47 value than expected for equilibrium precipitation, possibly due to kinetic isotope fractionation. Here we report Δ_47 values measured in natural speleothems from various cave settings, in carbonate produced by cave precipitation experiments, and in synthetic stalagmite analogs precipitated in controlled laboratory conditions designed to mimic natural cave processes. All samples yield lower Δ_47 and heavier δ^(18)O values than predicted by experimental calibrations of thermodynamic equilibrium in inorganic calcite. The amplitudes of these isotopic disequilibria vary between samples, but there is clear correlation between the amount of Δ_47 disequilibrium and that of δ^(18)O. Even pool carbonates believed to offer excellent conditions for equilibrium precipitation of calcite display out-of-equilibrium δ^(18)O and Δ_47 values, probably inherited from prior degassing within the cave system. In addition to these modern observations, clumped-isotope analyses of a flowstone from Villars cave (France) offer evidence that the amount of disequilibrium affecting Δ_47 in a single speleothem can experience large variations at time scales of 10 kyr. Application of clumped-isotope thermometry to speleothem records calls for an improved physical understanding of DIC fractionation processes in karst waters, and for the resolution of important issues regarding equilibrium calibration of Δ_47 in inorganic carbonates.
Published: 2011
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25. Boron isotopes as pH proxy: A new look at boron speciation in deep-sea corals using 11B MAS NMR and EELS

Author: Julien Trébosc, Jean-Pierre Cuif, Grégory Tricot, Dominique Blamart, Claire Rollion-Bard, Alexandre Mussi, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille
Subjects: Microprobe, 010504 meteorology & atmospheric sciences, Analytical chemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, chemistry.chemical_element, Isotopes of boron, 010502 geochemistry & geophysics, 01 natural sciences, Boric acid, chemistry.chemical_compound, chemistry, Geochemistry and Petrology, Magic angle spinning, Carbonate, Seawater, 14. Life underwater, Boron, Spectroscopy, 0105 earth and related environmental sciences, Nuclear chemistry
Abstract: Dissolved boron in modern seawater occurs in the form of two species, trigonal boric acid B(OH)3 and tetrahedral borate ion B ( OH ) 4 − . One of the key assumption in the use of boron isotopic compositions of carbonates as pH proxy is that only borate ions, B ( OH ) 4 − , are incorporated into the carbonate. Here, we investigate the speciation of boron in deep-sea coral microstructures (Lophelia pertusa specimen) by using high field magic angle spinning nuclear magnetic resonance (11B MAS NMR) and electron energy-loss spectroscopy (EELS). We observe both boron coordination species, but in different proportions depending on the coral microstructure, i.e. centres of calcification versus fibres. These results suggest that careful sampling is necessary before performing boron isotopic measurements in deep-sea corals. By combining the proportions of B(OH)3 and B ( OH ) 4 − determined by NMR and our previous ion microprobe boron isotope measurements, we propose a new equation for the relation between seawater pH and boron isotopic composition in deep-sea corals.
Published: 2011
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26. Northeastern Atlantic cold-water coral reefs and climate

Author: Matthias López Correa, Tjeerd C.E. van Weering, Eric Douville, Claudia Wienberg, Pål Buhl-Mortensen, J. Murray Roberts, Norbert Frank, Henk de Haas, Christine Hatté, Markus Hermann Eisele, André Freiwald, Dominique Blamart, Christophe Colin, Ben De Mol, Dierk Hebbeln, Jean-Pierre Henriet, David Van Rooij, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Senckenberg Meer, GZN Erlangen, Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), Center for Marine Environmental Sciences [Bremen] (MARUM), Universität Bremen, RCMG Ghent, Universiteit Gent = Ghent University (UGENT), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Royal Netherlands Institute for Sea Research (NIOZ), Institute of Marine Research [Bergen] (IMR), University of Bergen (UiB), School Life Science Centre Marine Biodiversity & Biotechnology, Heriot-Watt University [Edinburgh] (HWU), GRP Recerca Geociencies Marines, Universitat de Barcelona (UB), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Universiteit Gent = Ghent University [Belgium] (UGENT), and Université de Barcelonne
Subjects: Polar front, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, biology, Ecology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geology, Coral reef, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Oceanography, Mediterranean sea, Lophelia, 13. Climate action, Ice age, Temperate climate, 14. Life underwater, Reef, 0105 earth and related environmental sciences, Madrepora oculata
Abstract: International audience; U-series age patterns obtained on reef framework-forming cold-water corals collected over a nearly 6000-km-long continental margin sector, extending from off Mauritania (17 degrees N; northwest Africa) to the southwestern Barents Sea (70 degrees N; northeastern Europe), reveal strong climate influences on the geographical distribution and sustained development of these ecosystems. Over the past three glacial-interglacial cycles, framework-forming cold-water corals (Lophelia pertusa and Madrepora oculata) seem to have predominantly populated reefs, canyons, and patches in the temperate East Atlantic and the Mediterranean Sea. Above 50 degrees N corals colonize reefs in the northern East Atlantic primarily during warm climate periods with the biogeographic limit advancing from similar to 50 degrees N to similar to 70 degrees N. We propose that north-south oscillations of the biogeographic limit of reef developments are paced by ice ages and may occur synchronously with north-south displacement of cold nutrient-rich intermediate waters and surface productivity related to changes of the polar front.
Published: 2011
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27. Anaerobic oxidation of methane in a cold-water coral carbonate mound from the Gulf of Cadiz

Author: Lois Maignien, Jean Henriet, Anneleen Foubert, Julie Reveillaud, Nico Boon, D. Depreiter, L. De Mol, Dominique Blamart, Pascal Boeckx, Universiteit Gent = Ghent University [Belgium] (UGENT), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Universiteit Gent = Ghent University (UGENT), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Clathrate hydrate, Geochemistry, 010502 geochemistry & geophysics, 01 natural sciences, Seafloor spreading, Methane, chemistry.chemical_compound, Isotopic signature, Oceanography, chemistry, Anaerobic oxidation of methane, Dissolved organic carbon, General Earth and Planetary Sciences, Carbonate, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology, 0105 earth and related environmental sciences, Mud volcano
Abstract: International audience; The Gulf of Cadiz is an area of mud volcanism and gas venting through the seafloor. In addition, several cold-water coral carbonate mounds have been discovered at the Pen Duick escarpment amidst the El Arraiche mud volcano field on the Moroccan margin. One of these mounds -named Alpha mound- has been studied to examine the impact of the presence of methane on pore-water geochemistry, potential sulphate reduction (SR) rate and dissolved inorganic carbon (DIC) budget of the mound in comparison with off-mound and off-escarpment locations. Pore-water profiles of sulphate, sulphide, methane, and DIC from the on-mound location showed the presence of a sulphate to methane transition zone at 350 cm below the sea floor. This was well correlated with an increase in SR activity. (13)C-depleted DIC at the transition zone (-21.9aEuro degrees vs. Vienna Pee Dee Belemnite) indicated that microbial methane oxidation significantly contribute to the DIC budget of the mound. The Alpha mound thus represents a new carbonate mound type where the presence and anaerobic oxidation of methane has an important imprint on both geochemistry and DIC isotopic signature and budget of this carbonate mound.
Published: 2010
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28. In situ measurements of oxygen isotopic composition in deep-sea coral, Lophelia pertusa: Re-examination of the current geochemical models of biomineralization

Author: Jean-Pierre Cuif, Dominique Blamart, Claire Rollion-Bard, Yannicke Dauphin, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: In situ, Mineralization (geology), 010504 meteorology & atmospheric sciences, biology, Coral, Aragonite, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mineralogy, engineering.material, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Deep sea, Lophelia, Geochemistry and Petrology, engineering, Rayleigh fractionation, ComputingMilieux_MISCELLANEOUS, Geology, 0105 earth and related environmental sciences, Biomineralization
Abstract: We present ion microprobe measurements of oxygen isotopic compositions in the deep-sea coral Lophelia pertusa . Compared to bulk skeletal aragonite fibres, the EMZ (early mineralization zone), near the inside of the calyx, was systematically depleted in 18 O. Rayleigh fractionation from a semi-closed fluid reservoir does not explain this and other geochemical differences. Furthermore, pH values estimated from skeletal δ 11 B data are inconsistent with the idea that EMZ (or centres of calcification) 18 O depletion reflects a more alkaline calcification environment. Our data, combined with microstructural and geochemical observations, indicate that the aragonitic fibres and EMZ are formed by a compartmentalized mineralization calicoblastic ectoderm, which exerts strong biological control on the composition of the skeleton. Hence, we propose a new model whereby amorphous calcium carbonates (ACC) are precursors to the EMZ, whereas the fibre precipitation is probably governed by kinetic processes.
Published: 2010
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29. Early Neanderthal constructions deep in Bruniquel Cave in southwestern France

Author: Jacques Jaubert, Michel Soulier, Serge Delaby, François Lévêque, Catherine Ferrier, Damien Deldicque, Christian Burlet, Frédéric Maksud, Jean-Noël Rouzaud, Hai Cheng, Édouard Régnier, Dominique Genty, Pascal Mora, Xavier Muth, R. Lawrence Edwards, Sophie Verheyden, Hubert Camus, François Lacrampe-Cuyaubère, Dominique Blamart, Frédéric Santos, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Earth System Sciences, Analytical, Environmental & Geo-Chemistry, and Chemistry
Subjects: construction, 010506 paleontology, Neanderthal, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Stalagmite, 01 natural sciences, Fires, Cave, biology.animal, cave, Animals, 0601 history and archaeology, History, Ancient, 0105 earth and related environmental sciences, Neanderthals, geography, 060101 anthropology, Multidisciplinary, geography.geographical_feature_category, biology, Construction Materials, Construction Industry, 06 humanities and the arts, Limiting, Cave-in, Archaeology, Caves, Facility Design and Construction, Period (geology), France, fire
Abstract: International audience; Very little is known about Neanderthal cultures1, particularly early ones. Other than lithic implements and exceptional bone tools2, very few artefacts have been preserved. While those that do remain include red and black pigments3 and burial sites4, these indications of modernity are extremely sparse and few have been precisely dated, thus greatly limiting our knowledge of these predecessors of modern humans5. Here we report the dating of annular constructions made of broken stalagmites found deep in Bruniquel Cave in southwest France. The regular geometry of the stalagmite circles, the arrangement of broken stalagmites and several traces of fire demonstrate the anthropogenic origin of these constructions.Uranium-series dating of stalagmite regrowths on the structures and on burnt bone, combined with the dating of stalagmite tips in the structures, give a reliable and replicated age of 176.5 thousand years (±2.1 thousand years), making these edifices among the oldest known well-dated constructions made by humans. Their presence at 336 metres from the entrance of the cave indicates that humans from this period had already mastered the underground environment, which can be considered a major step in human modernity.
Published: 2015
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30. Development of laser ablation multi-collector inductively coupled plasma mass spectrometry for boron isotopic measurement in marine biocarbonates: new improvements and application to a modern Porites coral

Author: François, Thil, Dominique, Blamart, Caroline, Assailly, Claire E, Lazareth, Thierry, Leblanc, John, Butsher, and Eric, Douville
Subjects: Isotopes, Carbonates, Animals, Laser Therapy, Anthozoa, Mass Spectrometry, Boron
Abstract: Laser Ablation coupled to Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICPMS) is a powerful tool for the high-precision measurement of the isotopic ratios of many elements in geological samples, with the isotope ratio ((11) B/(10) B) of boron being used as an indicator of the pH of oceanic waters. Most geological samples or standards are polished and ablation occurs on flat surfaces. However, the shape and the irregularities of marine biocarbonates (e.g., corals, foraminifera) can make precise isotopic measurements of boron difficult. Even after polishing, the porosity properties and the presence of holes or micro-fractures affect the signal and the isotopic ratio when ablating the material, especially in raster mode.The effect of porosity and of the crater itself on the (11) B signal and the isotopic ratio acquired by LA-MC-ICPMS in both raster and spot mode was studied. Characterization of the craters was then performed with an optical profilometer to determine their shapes and depths. Surface state effects were examined by analyzing the isotopic fractionation of boron in silicate (NIST-SRM 612 and 610 standards) and in carbonate (corals).Surface irregularities led to a considerable loss of signal when the crater depth exceeded 20 µm. The stability and precision were degraded when ablation occurred in a deep cavity. The effect of laser focusing and of blank correction was also highlighted and our observations indicate that the accuracy of the boron isotopic ratio does not depend on the shape of the surface. After validation of the analytical protocol for boron isotopes, a raster application on a Porites coral, which grew for 18 months in an aquarium after field sampling, was carried out.This original LA-MC-ICPMS study revealed a well-marked boron isotope ratio temporal variability, probably related to growth rate and density changes, irrespective of the pH of the surrounding seawater. Copyright © 2015 John WileySons, Ltd.
Published: 2015

31. A high-resolution fluid inclusion δ18O record from a stalagmite in SW France: modern calibration and comparison with multiple proxies

Author: Hubert B. Vonhof, Edwige Pons-Branchu, Monique Pierre, Clément Bourdin, Jiaoyang Ruan, Hai Cheng, Dominique Blamart, Dominique Genty, Eric Douville, R. Lawrence Edwards, Inga Labuhn, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] ( LSCE ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), Faculty of Earth and Life Science, Amsterdam, Faculty of Earth and Life Science, Centre de Recherches Pétrographiques et Géochimiques ( CRPG ), Université de Lorraine ( UL ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Faculty of Earth and Life Sciences [Amsterdam] (FALW), Vrije Universiteit Amsterdam [Amsterdam] (VU), Paléocéanographie (PALEOCEAN), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Archeology, Stalactite, 010504 meteorology & atmospheric sciences, δ18O, Geochemistry, Speleothem, Stalagmite, 010502 geochemistry & geophysics, 01 natural sciences, Isotopes of oxygen, chemistry.chemical_compound, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Fluid inclusions, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Geomorphology, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Calcite, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, geography, geography.geographical_feature_category, Stable isotope ratio, Geology, 15. Life on land, chemistry, 13. Climate action
Abstract: The δ 18 O of speleothem fluid inclusions can provide information about local climate and the atmospheric circulation if the fate of oxygen isotopes from precipitation to the stalagmite is well understood. At Villars cave, SW France, the present-day relationship between the δ 18 O of precipitation and the δ 18 O of cave drip water has been determined by previous monitoring studies. In this article, we examine the link between drip water and fluid inclusions in speleothems from the same cave, and investigate whether the fossil water in the stalagmites provides a record of the isotopic composition of precipitation. Replicated fluid inclusion isotope measurements ( δ D and δ 18 O) from two modern calcite samples, which had precipitated under the monitored stalactites, are in agreement with the corresponding contemporaneous drip waters. The drip water, in turn, represents average pluri-annual precipitation. This gives strong evidence that the isotopic composition of the infiltrating water is preserved in the pores of speleothem calcite, thus providing a record of average precipitation δ 18 O at the site. Furthermore, we measured isotope ratios in fluid inclusions in the stalagmite vil-stm1, a 2300 year old sample with a high growth rate (up to 0.6 mm yr −1 ) and a high water content, which allows a high-resolution reconstruction of the drip water isotopic composition covering the last two millennia. The stalagmite is well dated by 13 U–Th ages and the counting of annual growth layers. The fluid inclusion δ 18 O varies by 2‰, with high δ 18 O values in Medieval times, and low values during the Little Ice Age, indicating a temperature influence on precipitation δ 18 O. However, temperature change alone cannot account for the full range of variability observed. Other proxies measured in the same stalagmite indicate that the cave environment has undergone substantial changes during this period: Stable isotopes and trace element concentrations in calcite show large variations, with amplitudes similar to those found in other Villars speleothems during large climatic shifts such as Dansgaard–Oeschger events or glacial–interglacial transitions. In the context of the last 2000 years, the proxy variability cannot be attributed to climate alone, but is likely influenced by anthropogenic deforestation and the associated changes in carbon dynamics and hydrology. These changes might also have an influence on the isotope ratios in drip water relative to precipitation, e.g. through an altered evaporation–transpiration ratio. Nevertheless, despite some common trends in all proxy records, the marked shifts in the other proxies are not seen in the fluid inclusion stable isotopes, which gives evidence that the relationship between precipitation and drip water δ 18 O in the past was similar to present-day conditions, and not much affected by the anthropogenic impact. A replication of the fluid inclusion isotope record using stalagmites from the same region will be necessary to determine whether local cave processes or large-scale temperature and atmospheric circulation dominate the fluid inclusion δ 18 O signal, and in how far the fluid inclusions can provide a direct record of precipitation δ 18 O.
Published: 2015
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32. Evolution of fault permeability during episodic fluid circulation : evidence for the effects of fluid–rock interactions from travertine studies (Utah–USA)

Author: Emanuelle Frery, Nadine Ellouz-Zimmerman, Rudy Swennen, Dominique Blamart, Jean-Pierre Gratier, Pierre Deschamps, Jean Braun, Christelle Loiselet, Bruno Hamelin, IFP Energies nouvelles (IFPEN), Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Tectonique reliefs et bassins, Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Aix Marseille Université (AMU), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Department of Earth and Environmental Sciences [Leuven] (EES), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Thermodynamic state, Outcrop, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], Petrography, Paleontology, Vein sealing, Travertine calibration, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, 0105 earth and related environmental sciences, Earth-Surface Processes, Fault activity, Aragonite, Structural geology, Crust, CO2-enriched fluids, Fluid circulation and leakage, Permeability (earth sciences), Geophysics, engineering, human activities, Geology, Chronology
Abstract: © 2015 Elsevier B.V.. Faults are known to be important pathways for fluid circulation within the crust. The transfer properties along faults can evolve over time and space. The Little Grand Wash and Salt Wash normal faults, located on the Colorado Plateau, are well known examples of natural CO2 leakage systems from depth to surface. Previous studies dated and established a chronology of CO2-enriched fluid source migration along the fault traces and linked the aragonite veins observed close to Crystal Geyser to CO2-pulses. However, multiple circulation events recorded along a given fault segment deserve to be studied in minute detail in order to unravel the chronology of these events, precipitation processes and associated mechanisms. A combination of structural geology, petrography, U/Th dating, oxygen and carbon isotope analysis were used to study the fault related CO2-enriched paleo-circulations in order to build a conceptual model of CO2-circulation along the faults. This study resulted in the precise descriptions of the features attesting CO2-enriched fluid circulation by a characterization of their relationship and architecture at the outcrop scale. These features are witnesses of a large range of circulation/sealing mechanisms, as well as changes in fluid chemistry and thermodynamic state of the system, providing evidence for (i) the evolution of the fluid through a pathway from depth to the surface and (ii) different cycles of fault opening and sealing. Large circulation events linked with fault opening/sealing are observed and calibrated in nature with millennial circulation and sealing time-lapses. Numerical modelling indicates that such sealing timescale can be explained by the introduction of a fault sealing factor that allows modifying permeability with time and that is calibrated by the natural observations. ispartof: Tectonophysics vol:651 pages:121-137 status: published
Published: 2015
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33. Open system U-series ages of corals from a subsiding reef in New Caledonia: Implications for sea level changes, and subsidence rate

Author: Guy Cabioch, Dominique Blamart, Christophe Colin, Philippe Jean-Baptiste, M. Tressens-Fedou, Norbert Frank, Laurent Turpin, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléo-environnements tropicaux et variabilité climatique (PALEOTROPIQUE), Paléocéanographie (PALEOCEAN), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Géosciences Paris Saclay (GEOPS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Marine isotope stage, 010504 meteorology & atmospheric sciences, Coral, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, sea level, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, New Caledonia, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, coral, Reef, ComputingMilieux_MISCELLANEOUS, Sea level, Holocene, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, U series open system dating, Coral reef, ThU dating, Geophysics, Oceanography, subsidence rate, 13. Climate action, Space and Planetary Science, Interglacial, Quaternary, Geology
Abstract: International audience; On the Amedee islet, 4 drill cores were recovered from the barrier reef of Western New Caledonia. The coral reef is slowly subsiding and is thus percolated by sea water during sea level highstands. The cores sample a similar to 10 m thick Holocene reef overlying a 24 m thick reef of marine isotope stage (MIS) 5.5, which in turn overlies older reef material from MIS 7.5 and beyond. (U-234/U-238) and (Th-230/U-238) ratios and Th-232 were determined by thermal ionization mass spectrometry on aragonitic coral samples that were carefully investigated using-X-ray diffraction and scanning electron microscopy. The petrographic study shows an increasing coral weathering with growing coral age that causes different degree of U-series open system behavior and 232Th accumulation. Holocene corals exhibit a small degree of early diagenesis and yield Th-230/U-238 ages according to the Holocene sea level rise from similar to 8200 years to 5000 years BP. Corals from the last Interglacial section have experienced more frequent replacement of aragonite fibers and minor dissolution, and U-series open system behavior is evident. To estimate the impact of recoil processes and alteration on the U-series system two models by Villemant and Feuillet [B. Villemant, N. Feuillet, Dating open systems by the U-238-U-234-Th-230 method: application to Quaternary reef terraces, Earth and Planetary Science Letters 210(2003) 105-118.] and Thompson et al. [W. G. Thompson, M. W. Spiegelman, S. L. Goldstein, R. C. Speed, An open-system model for U-series age determinations of fossil corals, Earth and Planetary Science Letters 210(2003) 365-381.] have been tested. These models yield identical ages within uncertainty, which are in agreement to the sea level history of the past 250,000 years, as long as physico-chemical alteration and re-crystallization is small. Consequently, we were able to estimate the subsidence rate from the subsidence observed between the end of MIS 5.5 and the early Holocene, which is similar to 0.16 +/- 0.04 m per 1000 years. In addition, by using this subsidence rate and the sea level highstand of +6 +/- 3 m during MIS 5.5 we can estimate the sea level highstand at 244,000 (MIS 7.5) to be between +2 m to -2 m, respectively. Corals from underneath the marine isotope stage 7.5 sequence show more significant dissolution, increasing re-crystallization, elevated 232Th, and excess U-234 and Th-230. Here the Villemant and Feuillet [B. Villemant, N. Feuillet, Dating open systems by the U-238-U-234-Th-230 method: application to Quaternary reef terraces, Earth and Planetary Science Letters 210(2003) 105-118.] model fails to predict ages, but the Thompson et al. [W.G. Thompson, M. W. Spiegelman, S. L. Goldstein, R. C. Speed, An open-system model for U-series age determinations of fossil corals, Earth and Planetary Science Letters 210(2003) 365-381.] model was applicable predicting ages between 355,000 to > 430,000 years, i.e. coral growth potentially during MIS 9 or 11. (c) 2006 Elsevier B.V. All rights reserved.
Published: 2006
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34. Timing and dynamics of the last deglaciation from European and North African δ13C stalagmite profiles—comparison with Chinese and South Hemisphere stalagmites

Author: M. Bakalowicz, Karine Wainer, John Hellstrom, Najiba Chkir, V. Plagnes, Ch. Causse, Dominique Genty, Bassam Ghaleb, Dominique Blamart, Kamel Zouari, François Bourges, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Centre de recherche sur la dynamique du système Terre (GEOTOP), Université de Montréal (UdeM)-McGill University = Université McGill [Montréal, Canada]-École Polytechnique de Montréal (EPM)-Concordia University [Montreal]-Université du Québec à Rimouski (UQAR)-Université du Québec à Montréal = University of Québec in Montréal (UQAM)-Université du Québec en Abitibi-Témiscamingue (UQAT), Milieux Environnementaux, Transferts et Interactions dans les hydrosystèmes et les Sols (METIS), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Station d’Ecologie Expérimentale du CNRS à Moulis (SEEM), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Radio-Analyses et Environnement (LRAE), École Nationale d'Ingénieurs de Sfax | National School of Engineers of Sfax (ENIS), University of Melbourne, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), École Polytechnique de Montréal (EPM)-McGill University = Université McGill [Montréal, Canada]-Université de Montréal (UdeM)-Université du Québec en Abitibi-Témiscamingue (UQAT)-Université du Québec à Rimouski (UQAR)-Concordia University [Montreal]-Université du Québec à Montréal = University of Québec in Montréal (UQAM), École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Archeology, Global and Planetary Change, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Northern Hemisphere, Speleothem, Geology, Stalagmite, Older Dryas, 010502 geochemistry & geophysics, 01 natural sciences, Allerød oscillation, Oceanography, Preboreal, 13. Climate action, Deglaciation, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Southern Hemisphere, ComputingMilieux_MISCELLANEOUS, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences
Abstract: The last deglaciation and its climatic events, such as the Bolling–Allerod (BA) and the Younger–Dryas (YD), have been clearly recorded in the δ 13 C profiles of three stalagmites from caves from Southern France to Northern Tunisia. The three δ 13 C records, dated by thermal ionization mass spectrometric uranium–thorium method (TIMS), show great synchroneity and similarity in shape with the Chinese cave δ 18 O records and with the marine tropical records, leading to the hypothesis of an in-phase (between 15.5 and 16 ka ∼±0.5 ka) postglacial warming in the Northern Hemisphere, up to at least 45°N. The BA transition appears more gradual in the speleothem records than in the Greenland records and the Allerod seems warmer than the Bolling, showing here close similarities with other marine and continental archives. A North–South gradient is observed in the BA trend: it cools in Greenland and warms in our speleothem records. Several climatic events are clearly recognizable: a cooler period at about 14 ka (Older Dryas (OD)); the Intra-Allerod Cold Period at about ∼13.3 ka; the YD cooling onset between 12.7 and 12.9±0.3 ka. Similar to the BA, the YD displays a gradual climate amelioration just after its onset at 12.75±0.25 ka, up to the Preboreal, and is punctuated by a short climatic event at 12.15 ka. Even though the Southern Hemisphere stalagmite records seem to indicate that the postglacial warming started about ∼3 ka±1.8 ka earlier in New Zealand (∼41 °S), and about ∼1 to ∼2 ka earlier in South Africa (24.1 °S), large age uncertainties, essentially due to slow growth rates, make the comparison still perilous. The overall δ 13 C speleothem record seems to follow a baseline temperature increase controlled by the increase in insolation and punctuated by cold events possibly due to the N-America freshwater lake discharges.
Published: 2006
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35. Quaternary sediment dynamics in the Belgica mound province, Porcupine Seabight: ice-rafting events and contour current processes

Author: Andrew J. Wheeler, Jean-Pierre Henriet, D. Van Rooij, M. Kozachenko, Thomas G. Richter, Dominique Blamart, Universiteit Gent = Ghent University [Belgium] (UGENT), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Royal Netherlands Institute for Sea Research (NIOZ), University College Cork (UCC), Universiteit Gent = Ghent University (UGENT), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, coral banks, ANE, Porcupine Seabight, Glacial deposits, 010502 geochemistry & geophysics, 01 natural sciences, Quaternary, Paleontology, Porcupine Basin, 14. Life underwater, Stadial, Glacial period, Sedimentology, Anthozoa [Sea anemones], [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Ice rafting, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, ice-rafting event, geography.geographical_feature_category, Contourite, Marine sedimentation, Oceanography, Bottom currents, 13. Climate action, Earth and Environmental Sciences, Interglacial, General Earth and Planetary Sciences, Ice sheets, contourite, Ice sheet, British-Irish ice sheet, A, Atlantic, Geology
Abstract: The Belgica cold-water coral banks on the eastern slope of the Porcupine Seabight are closely associated with bottom currents. In order to better understand the local temporal and spatial characteristics, as well as the palaeoclimatologic influences, a 26 m long core, taken on a small contourite drift, was studied. This sediment record of approximately 100 ka BP reveals new insights into the regional glacial and sedimentary processes, which are intrinsically linked to several geological, climatological, biological and hydrodynamic variables. The glacial sequences in the core contain six ice-rafting events (IRE). They are comparable with the North Atlantic Heinrich Events, although their characteristics show dominant influences from the proximal British-Irish Ice Sheet (BIIS). These IRE have a low magnetic susceptibility and are deposited during two or three ice-rafting pulses. The record of ice-rafting suggests a millennial-scaled BIIS destabilisation and confirms the start of a final retreat about 25 ka ago. Additionally, the glacial sequence corresponds to a muddy contourite, influenced by bottom-current strength variations during interstadials, possibly triggered by sporadic reintroductions of Mediterranean Outflow Water in a glacial North Atlantic Ocean. The interglacial sequence features an 11-m thick deep-water massive sand unit, probably deposited under a high-energy bottom-current regime.
Published: 2006
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36. Microanalysis of C and O isotopes of azooxanthellate and zooxanthellate corals by ion microprobe

Author: Anne Juillet-Leclerc, Jean-Pierre Cuif, Claire Rollion-Bard, Dominique Blamart, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Microprobe, 010504 meteorology & atmospheric sciences, biology, δ18O, Analytical chemistry, Aquatic Science, 010502 geochemistry & geophysics, biology.organism_classification, 01 natural sciences, Isotopes of oxygen, Oceanography, Lophelia, Isotopes of carbon, Galaxea fascicularis, Kinetic fractionation, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Isotope analysis
Abstract: We have determined the δ18O and δ13C values of azooxanthellate (Lophelia pertusa) and zooxanthellate (Porites lutea) corals at a micrometer scale using an ion microprobe (SIMS—secondary ion mass spectrometry). In P. lutea, centers of calcification are small (10 to 15 μm) and difficult to locate during measurements. In L. pertusa, they are large (50 μm) and arranged in lines of centers of calcification. Our results show that centers of calcification in L. pertusa have a restricted range of variation in δ18O [-2.8±0.3‰ (PDB)], and a larger range in δ13C [14.3 to 10.9‰ (PDB)]. Surrounding skeletal fibers exhibit large isotopic variation both for C and O (up to 12‰), and δ13C and δ18O are positively correlated. The C and O isotopic compositions of the center of calcification deviate from this linear trend at the lightest δ18O values of the surrounding fibers. Ion microprobe results on P. lutea demonstrate also a large range of variation for the δ18O values (up to 10‰). No correlation is found with C isotopes that exhibit, in comparison with L. pertusa, a small range of variation (2‰). This variation of δ18O at a micrometer scale is probably the result of two processes: (1) an isotopic equilibrium calcification with 1 pH unit variation in the calcification fluid as indicated by direct measurements of coelenteron pH in the coral Galaxea fascicularis (Al-Horani et al. 2003) and (2) a kinetic fractionation. The δ13C apparent disequilibrium in P. lutea may be the result of mixing between metabolic CO2 (respiration) and dissolved inorganic carbon (DIC) coming directly from seawater.
Published: 2003
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37. Precise dating of Dansgaard–Oeschger climate oscillations in western Europe from stalagmite data

Author: Andy Baker, Sandra Van-Exter, Mabs Gilmour, Dominique Blamart, Jean Jouzel, Dominique Genty, R Ouahdi, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), The Open University [Milton Keynes] (OU), Newcastle University [Newcastle], Hydrosciences Montpellier (HSM), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Geologic Sediments, Time Factors, 010504 meteorology & atmospheric sciences, Climate, Speleothem, Stalagmite, Oxygen Isotopes, 010502 geochemistry & geophysics, 01 natural sciences, Isotopes of oxygen, Soil, Ice core, Cave, Animals, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Carbon Isotopes, geography, Multidisciplinary, geography.geographical_feature_category, Ice, Temperature, Humidity, Carbon Dioxide, Plants, Cold Climate, Carbon, Oceanography, 13. Climate action, Isotopes of carbon, France, Geology, Chronology
Abstract: The signature of Dansgaard-Oeschger events--millennial-scale abrupt climate oscillations during the last glacial period--is well established in ice cores and marine records. But the effects of such events in continental settings are not as clear, and their absolute chronology is uncertain beyond the limit of (14)C dating and annual layer counting for marine records and ice cores, respectively. Here we present carbon and oxygen isotope records from a stalagmite collected in southwest France which have been precisely dated using 234U/230Th ratios. We find rapid climate oscillations coincident with the established Dansgaard-Oeschger events between 83,000 and 32,000 years ago in both isotope records. The oxygen isotope signature is similar to a record from Soreq cave, Israel, and deep-sea records, indicating the large spatial scale of the climate oscillations. The signal in the carbon isotopes gives evidence of drastic and rapid vegetation changes in western Europe, an important site in human cultural evolution. We also find evidence for a long phase of extremely cold climate in southwest France between 61.2 +/- 0.6 and 67.4 +/- 0.9 kyr ago.
Published: 2003
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38. Fossil water in large stalagmite voids as a tool for paleoprecipitation stable isotope composition reconstitution and paleotemperature calculation

Author: Olivier Cattani, S. Falourd, Christiane Causse, Dominique Blamart, Valérie Plagnes, Dominique Genty, R Ouahdi, Sandra Van-Exter, Michel Stievenard, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Calcite, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Stable isotope ratio, Mineralogy, Geology, Stalagmite, 010502 geochemistry & geophysics, 01 natural sciences, chemistry.chemical_compound, Deuterium, Ice core, chemistry, Cave, Geochemistry and Petrology, Paleoclimatology, Fluid inclusions, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The deuterium content of macroscopic fluid inclusions, several millimetres large, observed on two stalagmite polished sections has been measured with high accuracy (
Published: 2002
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39. Corrigendum to 'Possible controls on Li, Na and Mg incorporation into aragonite coral skeletons' [Chem. Geol. 396 (2015) 98-111]

Author: Claire Rollion-Bard and Dominique Blamart
Subjects: Geochemistry and Petrology, Coral, Aragonite, engineering, Mineralogy, Geology, engineering.material
Published: 2017
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40. Late Miocene to early Pliocene climate variability off NW Africa (ODP Site 659)

Author: Zhifei Liu, Norbert Frank, Christophe Colin, Julien Gargani, Thomas G. Richter, Stéphanie Duchamp-Alphonse, Charlotte Skonieczny, Catherine Kissel, Aloys Bory, Dominique Blamart, Giuseppe Siani, François Thil, Yulong Zhao, Géosciences Paris Sud (GEOPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Marine Geology [Shanghai], Tongji University, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Geosystemes, FRE CNRS 3298, Université de Lille, Sciences et Technologies, Géochrononologie Traceurs Archéométrie (GEOTRAC), Royal Netherland, Institute for Sea Research, Climat et Magnétisme (CLIMAG), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Géosystèmes - FRE 3298
Subjects: geography, Plateau, geography.geographical_feature_category, Terrigenous sediment, Intertropical Convergence Zone, Paleontology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Oceanography, Monsoon, Convergence zone, Panoply, Cape verde, Mediterranean sea, 13. Climate action, Pliocene climate, Ecology, Evolution, Behavior and Systematics, Geology, ComputingMilieux_MISCELLANEOUS, Earth-Surface Processes
Abstract: A high resolution δ 18 O record obtained on benthic foraminifera ( Cibicides wuellerstorfi ) combined with clay mineralogy, major element concentrations and Sr–Nd isotopes have been investigated for the ODP Site 659 located off North Africa in order to reconstruct African monsoon intensity between 6.2 and 4.9 Myr. Mineralogical and geochemical results indicate that sedimentation on the Cape Verde plateau results from a mixture of sediments deriving from the neighbouring Saharan arid region and the wet African equatorial zone (Sahelian Band), characterised by a low and a high state of weathering, respectively. Past variations in terrigenous inputs from these areas allow us to track past extension and displacement of the West African Monsoon–ITCZ system. Maximal summer insolation induced a northward migration of the inter-tropical convergence zone (ITCZ), wetter conditions in the Sahel, and a diminishing of wind erosion over the South Sahara and Sahel. In addition, there was an increase in river input to the Cape Verde plateau of sediments derived from southern sedimentary sources, which are characterised by high kaolinite contents and CIA values and low K/Al and Ti/Al ratios. On the other hand, minimal summer insolation induced a southward movement of the ITCZ, drier climate in the Sahel and stronger easterly winds resulting in an increase in dust transport from the Sahara to the Cape Verde Plateau. Dust particles are characterised by high illite and smectite content and by a low chemical state of weathering (low CIA values and high K/Al and Ti/Al ratios). Finally, our results provide new clues regarding the re-flooding of the Mediterranean Sea at the end of the MSC (5.33 Myr). This event was associated with enhanced aridity in the Sahara, implying a reorganisation of the atmospheric circulation and a southward migration of the ITCZ.
Published: 2014
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41. Offshore-onshore linkages in the larval life history of sole in the gulf of lions (NW-Mediterranean)

Author: Audrey M. Darnaude, Yves Letourneur, Fabien Morat, Dominique Blamart, Mireille Harmelin-Vivien, Christophe Pécheyran, Hydrobiologie (UR HYAX), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Université de la Nouvelle-Calédonie (UNC), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Insulaire du Vivant et de l'Environnement (LIVE), and BUNC, Pole ID
Subjects: Mediterranean climate, Water mass, SOLEA SOLEA, STABLE ISOTOPE, media_common.quotation_subject, [SDV]Life Sciences [q-bio], Aquatic Science, Biology, Oceanography, AGE, medicine, RIVER FLOOD EVENT, 14. Life underwater, Metamorphosis, RHONE RIVER, Chemical composition, OTOLITH MICROCHEMISTRY, Otolith, media_common, Larva, Hatching, Ecology, fungi, Pelagic zone, [SDV] Life Sciences [q-bio], medicine.anatomical_structure, [SDE]Environmental Sciences, RHONE COURS D’EAU
Abstract: [Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE; International audience; Understanding individual dispersion from offshore natal areas to coastal nurseries during pelagic larval life is especially important for the sustainable management of exploited marine fish species. For several years, the hatching period, the larval life duration, the average growth rate and the otolith chemical composition (d13C, d18O, Sr:Ca and Ba:Ca) during the larval life were studied for young of the year (YOY) of sole collected in three main nurseries of the Gulf of Lions (GoL) (Thau, Mauguio and Berre). We investigated the spatial variation in the origin of the sole larvae which colonised the nurseries around the GoL, and whether temporal differences in environmental conditions during this life stage affected growth and larval life duration. The hatching period ranges from October to March, depending on year and site. Average ages at metamorphosis varied between 43 and 50 days, with the lowest and highest values consistently found for Mauguio and Berre, respectively. Otolith growth rates ranged between 2.7 and 3.2 mm d-1, with the lowest values in Thau and Mauguio and the highest in Berre. Otolith chemical composition during the larval life also varied, suggesting contrasted larval environmental histories in YOY among nurseries. In fishes from Berre and Mauguio, larval life was more influenced by the Rhone River, showing consistently higher larval Ba:Ca ratios (10/23 mmol mol-1) and lower d13C (-6.5/-6.1 pour mille) and d18O values (-1.6/0.1 pour mille) than for Thau (with Ba:Ca ratios < 8 mmol mol_1, d13C ~_2.3 pour mille and d18O ~1.5 pour mille). Differences in larval otolith composition were observed for 2004, with higher Ba:Ca and lower d13C and d18O values than in the two other years. These differences were explained by changes in composition and chemical signatures of water masses after an exceptional flooding event of the Rhone River in late 2003.
Published: 2014
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42. A coral δ18O record of ENSO driven sea surface salinity variability in Fiji (south -western tropical Pacific)

Author: Thierry Delcroix, Anne Julliet-Leclerc, Nolwenn Le Bec, Thierry Corrège, Dominique Blamart, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: Tropical pacific, 010504 meteorology & atmospheric sciences, δ18O, Coral, Southern oscillation, 010502 geochemistry & geophysics, 01 natural sciences, Salinity, Sea surface temperature, Geophysics, El Niño Southern Oscillation, Oceanography, 13. Climate action, Climatology, General Earth and Planetary Sciences, Environmental science, 14. Life underwater, Sea surface salinity, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences
Abstract: International audience; The role of salinity in the dynamics and thermodynamics of El Niño ‐ Southern Oscillation (ENSO) events is increasingly being investigated. However, instrumental records of salinity are scarce and short in the tropical Pacific, and there is a clear need for a reliable salinity proxy to extend our knowledge of ENSO through time. Here, we present 40 years of δ18O data from a Fiji coral (16°48′S–177°27′E). The coral δ18O signal integrates both sea surface temperature (SST) and sea surface salinity (SSS) variations. On a seasonal timescale, δ18O is mainly driven by SST changes whereas on an interannual ENSO timescale, it is almost exclusively affected by SSS variability. Since interannual fluctuations of SSS are rather well correlated to the Southern Oscillation Index in Fiji, coral δ18O can be used to reconstruct paleo‐salinity data with some level of confidence. This may help for tracking ENSO influences back in time.
Published: 2000
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43. Millennial climatic instability during penultimate glacial period recorded in a south-western France speleothem

Author: Valérie Plagnes, Dominique Genty, Dominique Blamart, Karine Wainer, Yves Quinif, Miryam Bar-Matthews, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Faculté Polytechnique de Mons, Service de Géologie Fondamentale et Appliquée, Structure et fonctionnement des systèmes hydriques continentaux (SISYPHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Mines Paris - PSL (École nationale supérieure des mines de Paris), Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), CNRS through the ANR PICC programme, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université Pierre et Marie Curie - Paris 6 (UPMC)-École pratique des hautes études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-MINES ParisTech - École nationale supérieure des mines de Paris
Subjects: 010504 meteorology & atmospheric sciences, Speleothem, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, chemistry.chemical_compound, Cave, Stage (stratigraphy), Glacial period, Stadial, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Climate instabilities, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Earth-Surface Processes, Stable isotopes, Calcite, geography, geography.geographical_feature_category, Paleontology, Penultimate glaciation, 15. Life on land, chemistry, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Climatology, Period (geology), Physical geography, Geology
Abstract: International audience; This study focuses on an earlier MIS (marine isotopic stage) 6 flowstone deposit (Vil-car-1 core, Villars Cave, SW-France) that recorded millennial scale climatic events. This speleothem provides a high resolution record of the penultimate glacial period on mid-latitude land. The flowstone high growth rate and the episodes with depleted calcite delta C-13(c) values suggest that marine isotopic substage 6e environmental conditions were relatively warm and humid. Its delta C-13(c) profile clearly displays five main climatic oscillations from 177 to 165 ka, correlated with stadial-interstadial events. Similarly to the MIS3 period, the transitions in between those interstadials and stadials are characterised by abrupt changes and intra-interstadial variability is observed. (C) 2013 Elsevier B.V. All rights reserved.
Published: 2013
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44. Preliminary indication of ontogenetic and spatial variations in the whole otolith isotopic and elemental signatures of Solea solea in the Gulf of Lions (NW Mediterranean)

Author: Michel Robert, Raymonde Lecomte-Finiger, Dominique Blamart, Yves Letourneur, Fabien Morat, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Laboratoire Insulaire du Vivant et de l'Environnement (LIVE), Université de la Nouvelle-Calédonie (UNC), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Interactions Hôtes-Pathogènes-Environnements (IHPE), Université de Perpignan Via Domitia (UPVD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), and La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 0106 biological sciences, Common sole, Mediterranean climate, laguna costera, [SDV]Life Sciences [q-bio], río Ródano, coastal lagoon, SH1-691, Aquatic Science, Oceanography, 010603 evolutionary biology, 01 natural sciences, lcsh:Aquaculture. Fisheries. Angling, Predation, river rhône, Mediterranean sea, [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology, medicine, stable isotope, Aquaculture. Fisheries. Angling, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, microquímica de los otolitos, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, ComputingMilieux_MISCELLANEOUS, Otolith, lcsh:SH1-691, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, peces planos, biology, Ecology, Soleá, 010604 marine biology & hydrobiology, isótopos estables, River Rhône, biology.organism_classification, otolith microchemistry, medicine.anatomical_structure, Habitat, Benthic zone, flatfish, [SDE.BE]Environmental Sciences/Biodiversity and Ecology
Abstract: Knowledge of fish life cycles is important for exploited species. In the Mediterranean Sea, catches of common sole (Solea solea) have fluctuated widely since the 1970s. Solea solea displays an ontogenetic shift in habitat: sole larvae are marine, juveniles inhabit shallow marine waters and coastal lagoons and adults inhabit deeper marine waters. Although the results of this study were obtained using only a small set of individuals, the otolith elemental composition and isotopic ratios were investigated for the three life stages (post-larval, juvenile and adult) in order to acquire a better knowledge of the variability in environmental conditions experienced by the common sole at each life stage in the NW Mediterranean. Moreover, this study provides the first evaluation of the potential of whole otolith microchemistry for investigating habitat connectivity in sole populations from the Gulf of Lions. The elemental and isotopic signatures of otoliths of post-larvae captured in various environments appear to show variations related to the River Rhône inputs (high Ba/Ca and low Sr/Ca ratios). Juveniles appear to show significant variations in otolith elemental and isotopic compositions depending not only on the physico-chemical properties of water in the nurseries they inhabit (Rhône River, Thau or Mauguio lagoons), but also as a result of variations in the chemical composition of their surrounding sediments and in their benthic prey. Adults exhibit otolith differences for isotopic ratios only, which is probably linked to the River Rhône inputs. Finally, several significant relationships were observed between otolith elemental composition and fish size in specimens captured at the River Rhône mouth. However, these variations seem to be an indication of the composition acquired in each environment rather than a sign of ontogeny. El conocimiento del ciclo de vida es importante para las especies comerciales de peces. En el mar Mediterráneo, las capturas de lenguado común (Solea solea) han fluctuado ampliamente desde la década de los 70. Solea solea presenta un cambio de hábitat ontogenético, las larvas son marinas, los juveniles viven en aguas marinas y en lagunas costeras, y los adultos viven en aguas marinas más profundas. Aunque los resultados de este estudio fueron obtenidos usando sólo un número pequeño de individuos, la composición de elemental los otolitos y las relaciones isotópicas fueron investigados en las tres etapas de vida (post-larval, juveniles y adultos) con el fin de adquirir un mejor conocimiento de la variabilidad en las condiciones ambientales que experimenta el lenguado común en cada etapa de la vida en el mediterráneo noroccidental. Por otra parte, este trabajo permite una primera evaluación del potencial de toda la microquímica de otolitos para la investigación de la conectividad del hábitat en las poblaciones de lenguado en el Golfo de León. Las señales elementales e isotópicos de los otolitos de las post-larvas capturadas en diferentes entornos muestran variaciones en relación a los materiales aportados por del río Ródano (alta relación Ba/Ca y baja relación Sr/Ca). Los juveniles parecen mostrar variaciones significativas en la composición elemental e isotópica de los otolitos dependiendo no sólo de las propiedades físico-químicas del agua en los viveros que habitan (Thau, Mauguio o el río Ródano), sino también como resultado de las variaciones en la composición química de los sedimentos circundantes y de su presa béntica. Los adultos presentan únicamente diferencias en las relaciones isotópicas de los otolitos, que está probablemente vinculado a por materiales aportados por el río Ródano. Por último, se observaron varias relaciones significativas entre la composición elemental de los otolitos y el tamaño de los peces en las muestras capturadas en la desembocadura del río Ródano. Sin embargo, estas variaciones parecen ser una indicación de la composición adquirida en cada entorno, más que ser debidas a la ontogenia.
Published: 2012
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45. 13. Paléothermométrie marine

Author: Dominique Blamart, Marie-Alexandrine Sicre, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2011
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46. 12. Paléothermométrie géochimique

Author: Dominique Blamart, Christian France-Lanord, Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Catherine Jeandel et Rémy Mosseri (dir.), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2011
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47. The importance of the terrigenous fraction within a cold-water coral mound : A case study

Author: Christophe Colin, Hans Pirlet, Kris Latruwe, Frank Vanhaecke, Dominique Blamart, Anneleen Foubert, Norbert Frank, Rudy Swennen, Jean-Pierre Henriet, Veerle A.I. Huvenne, David Van Rooij, Mieke Thierens, Renard Centre of Marine Geology, Universiteit Gent = Ghent University (UGENT), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Biological, Earth and Environmental Sciences [Cork] (BEES), University College Cork (UCC), Dpt of Analytical Chemistry, RCMG Ghent, Department of Earth and Environmental Sciences, K.U. Leuven, Université Catholique de Louvain = Catholic University of Louvain (UCL), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Dpt of Geology & Geophysics, National Oceanography Centre (NOC), Gent University, Universiteit Gent = Ghent University [Belgium] (UGENT), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: 010506 paleontology, Challenger Mound, EUROPEAN CONTINENTAL-MARGIN, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Cold-water coral mound, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, LATE QUATERNARY SEDIMENTS, Sedimentary depositional environment, ROCKALL TROUGH, Geochemistry and Petrology, IRISH ICE-SHEET, Deglaciation, Glacial period, Sedimentology, North Altantic, 0105 earth and related environmental sciences, Terrigenous sediment, Porcupine Seabight, NORTHERN PORCUPINE SEABIGHT, Sediment, Geology, Last Glacial Maximum, HEINRICH LAYERS, Clay mineralogy, IODP EXP. 307, deep-sea corals, LAST GLACIAL MAXIMUM, 13. Climate action, Earth and Environmental Sciences, NE ATLANTIC, CARBONATE MOUND, Interglacial, Sr and Nd isotopes
Abstract: International audience; In the nineties, cold-water coral mounds were discovered in the Porcupine Seabight (NE Atlantic. west of Ireland). A decade later, this discovery led to the drilling of the entire Challenger cold-water coral mound (Eastern slope, Porcupine Seabight) during IODP Expedition 307. As more than 50% of the sediment within Challenger Mound consists of terrigenous material, the terrigenous component is equally important for the build-up of the mound as the framework-building corals. Moreover, the terrigenous fraction contains important information on the dynamics and the conditions of the depositional environment during mound development. In this study, the first in-depth investigation of the terrigenous sediment fraction of a cold-water coral mound is performed, combining clay mineralogy, sedimentology, petrography and Sr-Nd-isotopic analysis on a gravity core (MD01-2451G) collected at the top of Challenger Mound. Sr- and Nd-isotopic fingerprinting identifies Ireland as the main contributor of terrigenous material in Challenger Mound. Besides this, a variable input of volcanic material from the northern volcanic provinces (Iceland and/or the NW British Isles) is recognized in most of the samples. This volcanic material was most likely transported to Challenger Mound during cold climatic stages. In three samples, the isotopic ratios indicate a minor contribution of sediment deriving from the old cratons on Greenland, Scandinavia or Canada. The grain-size distributions of glacial sediments demonstrate that ice-rafted debris was deposited with little or no sorting, indicating a slow bottom-current regime. In contrast, interglacial intervals contain strongly current-sorted sediments, including reworked glacio-marine grains. The micro textures of the quartz-sand grains confirm the presence of grains transported by icebergs in interglacial intervals. These observations highlight the role of ice-rafting as an important transport mechanism of terrigenous material towards the mound during the Late Quaternary. Furthermore, elevated smectite content in the siliciclastic, glaciomarine sediment intervals is linked to the deglaciation history of the British-Irish Ice Sheet (BIIS). The increase of smectite is attributed to the initial stage of chemical weathering processes, which became activated following glacial retreat and the onset of warmer climatic conditions. During these deglaciations a significant change in the signature of the detrital fraction and a lack of coral growth is observed. Therefore, we postulate that the deglaciation of the BUS has an important effect on mound growth. It can seriously alter the hydrography, nutrient supply and sedimentation processes, thereby affecting both sediment input and coral growth and hence, coral mound development. (C) 2011 Elsevier B.V. All rights reserved.
Published: 2011
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48. Speleothem record of the last 180 ka in Villars cave (SW France): Investigation of a large δ18O shift between MIS6 and MIS5

Author: Yves Quinif, Dominique Genty, P. van Calsteren, Dominique Blamart, Yuri Dublyansky, Miryam Bar-Matthews, K. Wainer, M. Daëron, L. E. Thomas, Nicolas Caillon, Edwige Pons-Branchu, Hubert B. Vonhof, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Géoazur (GEOAZUR 6526), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Geological Survey of Israel (GSI), Geological Survey of Israel, Vrije Universiteit Amsterdam [Amsterdam] (VU), Leopold Franzens Universität Innsbruck - University of Innsbruck, Géochrononologie Traceurs Archéométrie (GEOTRAC), The Open University [Milton Keynes] (OU), Faculté polytechnique de Mons, Université de Mons (UMons), Sedimentology, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Calcite, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Archeology, Global and Planetary Change, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, δ18O, Speleothem, Geology, 010502 geochemistry & geophysics, 01 natural sciences, chemistry.chemical_compound, Paleontology, Cave, chemistry, Interglacial, Deglaciation, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: The Vil-car-1 flowstone core from Villars cave (SW France) provides one of the first European speleothem records extending back to 180 ka, based on UeTh TIMS and MC-ICP-MS measurements. The core offers a continuous record of Termination II and the Last Interglacial. The penultimate deglaciation is characterized by a prominent 5& depletion in calcite d 18 O. Determining which specific environmental factors
Published: 2011
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49. Dating the Lascaux cave gour formation

Author: Dominique Genty, M Touma, J. P. Dumoulin, John Hellstrom, R Weil, C Moreau, Julius Nouet, Dominique Blamart, Yannicke Dauphin, Hélène Valladas, S Konik, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National Préhistorique, De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (PACEA), Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Géochrononologie Traceurs Archéométrie (GEOTRAC), Paléocéanographie (PALEOCEAN), School of Earth Sciences [Melbourne], Faculty of Science [Melbourne], University of Melbourne-University of Melbourne, Laboratoire de mesure du carbone 14 (LMC14 - UMS 2572), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Interactions et dynamique des environnements de surface (IDES), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Calcite, 010506 paleontology, Archeology, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Stalagmite, Sapropel, 01 natural sciences, law.invention, chemistry.chemical_compound, Paleontology, Cave painting, Cave, chemistry, law, General Earth and Planetary Sciences, Carbonate, Radiocarbon dating, Geology, 0105 earth and related environmental sciences, Accelerator mass spectrometry
Abstract: Lascaux Cave is renowned for its outstanding prehistoric paintings, strikingly well-preserved over about 18,000 yr. While stalagmites and stalactites are almost absent in the cave, there is an extensive calcite flowstone that covered a large part of the cave until its opening for tourists during the 1950s. The deposit comprises a succession of calcite rims, or “gours,” which allowed seepage water to pond in large areas in the cave. Their possible role in preservation of the cave paintings has often been evoked, but until now this deposit has not been studied in detail. Here, we present 24 new radiocarbon accelerator mass spectrometry (AMS) and 6 uranium-thorium (U-Th) analyses from the calcite of the gours, 4 AMS 14C dates from charcoals trapped in the calcite, and 4 AMS 14C analyses on organic matter extracted from the calcite. Combining the calibrated 14C ages obtained on charcoals and organic matter and U-Th ages from 14C analyses made on the carbonate, has allowed the calculation of the dead carbon proportion (dcp) of the carbonate deposits. The latter, used with the initial atmospheric 14C activities reconstructed with the new IntCal09 calibration data, allows high-resolution age estimation of the gour calcite samples and their growth rates. The carbonate deposit grew between 9530 and 6635 yr cal BP (for dcp = 10.7 ± 1.8%; 2 σ) or between 8518 and 5489 yr cal BP (for dcp = 20.5 ± 1.9%; 2 σ). This coincides with humid periods that can be related to the Atlantic period in Europe and to Sapropel 1 in the eastern Mediterranean Sea. However, geomorphological changes at the cave entrance might also have played a role in the gour development. In the 1940s, when humans entered the cave for the first time since its prehistoric occupation, the calcite gours had already been inactive for several thousand years.
Published: 2011
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50. Variability of the northeast Atlantic sea surface Δ14C and marine reservoir age and the North Atlantic Oscillation (NAO)

Author: Bernard Métivier, Pascal Yiou, Martine Paterne, Stéphane Raynaud, Maurice Arnold, Nadine Tisnérat-Laborde, Dominique Blamart, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), and Institut National des Sciences Appliquées (INSA)-Université de Lyon
Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 010506 paleontology, Archeology, Global and Planetary Change, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, River runoff, Geology, Transit time, 01 natural sciences, Suess effect, Oceanography, 13. Climate action, North Atlantic oscillation, Ocean gyre, Period (geology), 14. Life underwater, Precipitation, Atlantic margin, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: We compiled new 14 C analyses of mollusc shells (bivalves and gastropods) of known age from the collection of the Museum National d’Histoire Naturelle de Paris and previously published data to investigate changes in the sea surface Δ 14 C and reservoir age in the northeast Atlantic sector (NEA) between 1823 and 1952 AD. The mollusc shells are mainly located off the Atlantic margin between 45°N and 60°N downstream of the North Atlantic Current (NAC). We show that the temporal variability of the NEA Δ 14 C is independent of the mollusc species, depth habitat, diet and latitudinal distribution. The quasi-null difference between mollusc Δ 14 C and the marine model indicate that the mollusc Δ 14 C reflects the Δ 14 C values of open marine conditions. Between 1823 and 1850 AD, the pre-anthropogenic mean of Δ 14 C is −45 ± 5‰, corresponding to a reservoir age of 380 ± 60 years and a Δ R value of −7 ± 50 years, in agreement with previous estimates. The Δ 14 C values show a significant long-term decrease of ∼12‰ from 1823 to 1952 AD attributed to changes in 14 C production between 1823 and 1900 AD and the Suess effect between 1900 and 1952 AD. Between 1885 and 1950 AD, Δ 14 C fluctuations of ∼10‰ up to 18‰ occurred in the northeast Atlantic, corresponding to reservoir age variations of ∼90 years up to 170 years. These fluctuations are very similar to changes of Δ 14 C in the southern Norwegian Sea. Spectral analyses of the NEA Δ 14 C exhibit quasi-periodic cycles of about 7.4 years, almost equivalent to the quasi-periodic cycles of the winter index of the North Atlantic Oscillation (NAO) with a period around 6.5 years. We find that changes of NEA Δ 14 C cannot be attributed to changes in river runoff or the precipitation/evaporation budget. The Δ 14 C lows (or high reservoir ages) correspond to the more intense phase of the winter NAO, with a time lag of ∼1–3 years. Such a time lag may reflect the eastward transit time of upstream changes originating in the Labrador Sea, then entrained within the NAC along with the subpolar gyre into the northeast Atlantic sector. During these events, we estimate that about 70% of the total transport in the NAC was due to water originating in the Labrador Sea.
Published: 2010
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