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Registros recuperados: 11 | |
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Fentimen, Robin; Feenstra, Eline; Ruggeberg, Andres; Hall, Efraim; Rime, Valentin; Vennemann, Torsten; Hajdas, Irka; Rosso, Antonietta; Van Rooij, David; Adatte, Thierry; Vogel, Hendrik; Frank, Norbert; Krengel, Thomas; Foubert, Anneleen. |
This study provides a detailed reconstruction of climatic events affecting a cold-water coral mound located within the East Melilla Coral Province (Southeast Alboran Sea) over the last 300 ky. Based on benthic foraminiferal assemblages, macrofaunal quantification, grain size analysis, sediment geochemistry, and foraminiferal stable isotope compositions, a reconstruction of environmental conditions prevailing in the region is proposed. The variations in planktonic and benthic δ18O values indicate that cold-water coral mound formation follows global climatic variability. Cold-water corals develop during both interglacial and glacial periods, although interglacial conditions would have allowed better proliferation. Environmental conditions during glacial... |
Tipo: Text |
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Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00635/74734/74724.pdf |
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Boavida, Joana; Becheler, Ronan; Choquet, Marvin; Frank, Norbert; Taviani, Marco; Bourillet, Jean-francois; Meistertzheim, Anne‐leila; Grehan, Anthony; Savini, Alessandra; Arnaud-haond, Sophie. |
Aim To infer cold‐water corals’ (CWC) post‐glacial phylogeography and assess the role of Mediterranean Sea glacial refugia as origins for the recolonization of the northeastern Atlantic Ocean. Location Northeastern Atlantic Ocean and Mediterranean Sea. Taxon Lophelia pertusa, Madrepora oculata. Methods We sampled CWC using remotely operated vehicles and one sediment core for coral and sediment dating. We characterized spatial genetic patterns (microsatellites and a nuclear gene fragment) using networks, clustering and measures of genetic differentiation. Results Inferences from microsatellite and sequence data were congruent, and showed a contrast between the two CWC species. Populations of L. pertusa present a dominant pioneer haplotype, local haplotype... |
Tipo: Text |
Palavras-chave: Cold-water corals; Deep-sea; Glacial marine refugia; Last Glacial Maximum; Lophelia pertusa; Madrepora oculata; Marine phylogeography. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00487/59864/63140.pdf |
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Wefing, Anne-marie; Arps, Jennifer; Blaser, Patrick; Wienberg, Claudia; Hebbeln, Dierk; Frank, Norbert. |
High-precision U-series dating of scleractinian cold-water corals is a key chronological tool for studies of past environmental and climate conditions. Here, we tested and optimized an automated chemical extraction system (ESI prepFAST-MC equipped with an Eichrom TRU-resin chromatographic column) for its ability to purify U and Th isotopes for mass spectrometric U-series dating at the sub-‰ precision level. Chemical yields are constantly high, on average around 90% for both U and Th. Analytical blanks are comparable to manual purification (< 0.15 pg U, 0.15 pg Th for a typical sample of 50 mg) and memory effects due to the recycling of the column are mostly insignificant as the carry-over fraction is about 10− 5 for Th and 10− 3 for U isotopes. However,... |
Tipo: Text |
Palavras-chave: U-series dating; PrepFAST-MC; Cold-water corals; South Atlantic; Angola; Past climate. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00409/52058/52761.pdf |
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Bonneau, Lucile; Colin, Christophe; Pons-branchu, Edwige; Mienis, Furu; Tisnerat-laborde, Nadine; Blamart, Dominique; Elliot, Mary; Collart, Tim; Frank, Norbert; Foliot, Lorna; Douville, Eric. |
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 ‐ 790 m water depth at the SW Rockall Trough margin. Our data, combined with previous published data, have allowed us to firstly estimate the occurrence of CWC at the SW Rockall Trough margin during the Holocene and, secondly, 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... |
Tipo: Text |
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Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00441/55260/56753.pdf |
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Wu, Qiong; Colin, Christophe; Liu, Zhifei; Thil, Francois; Dubois-dauphin, Quentin; Frank, Norbert; Tachikawa, Kazuyo; Bordier, Louise; Douville, Eric. |
εNd and normalized Rare Earth Elements (REE) patterns of benthic and planktonic foraminifera and Fe-Mn coatings precipitated on sediments have been investigated for the South China Sea (SCS) to (1) assess the reliability of the extraction of past seawater εNd in the SCS and to (2) reconstruct past hydrological changes during the last 25 kyr. Reductively cleaned mono-specific planktonic foraminifera (Globigerinoides ruber) and mixed benthic foraminifera in core-top sediments from 1500 to 2400 m display similar εNd values to those of the modern Pacific Deep Water (PDW) (εNd of −3.9 to −4.4). Furthermore, the εNd of the reductive cleaning solutions shows similar εNd values to ones obtained on cleaned foraminifera. Combined with PAAS-normalized REE patterns,... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00295/40582/39500.pdf |
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Frank, Norbert; Freiwald, Andre; Lopez Correa, Matthias; Wienberg, Claudia; Eisele, Markus; Hebbeln, Dierk; Van Rooij, David; Henriet, Jean-pierre; Colin, Christophe; Van Weering, Tjeerd; De Haas, Henk; Buhl-mortensen, Pal; Roberts, J. Murray; De Mol, Ben; Douville, Eric; Blamart, Dominique; Hatte, Christine. |
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... |
Tipo: Text |
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Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00214/32554/31025.pdf |
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De Mol, Lies; Van Rooij, David; Pirlet, Hans; Greinert, Jens; Frank, Norbert; Quemmerais-amice, Frederic; Henriet, Jean-pierre. |
In 1948, Le Danois reported for the first time the occurrence of living cold-water coral reefs, the so-called "massifs coralliens", along the European Atlantic continental margin. In 2008, a cruise with R/V Belgica was set out to re-investigate these cold-water corals in the Penmarc'h and Guilvinec Canyons along the Gascogne margin of the Bay of Biscay. During this cruise, an area of 560 km(2) was studied using multibeam swath bathymetry, CTD casts, ROV observations and USBL-guided boxcoring. Based on the multibeam data and the ROV video imagery, two different cold-water coral reef settings were distinguished. In water depths ranging from 260 to 350 m, mini mounds up to 5 m high, covered by dead cold-water coral rubble, were observed. In between these... |
Tipo: Text |
Palavras-chave: Bay of Biscay; Continental margin; Canyons; Cold-water corals; Lophelia; Madrepora. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14632/13318.pdf |
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Frank, Norbert; Ricard, Estelle; Lutringer-paquet, Audrey; Van Der Land, Cees; Colin, Christophe; Blamart, Dominique; Foubert, Anneleen; Van Rooij, David; Henriet, Jean-pierre; De Haas, Henk; Van Weering, Tjeerd. |
U-series dating of constructional cold-water corals is a powerful tool to reconstruct the evolution of corals on carbonate mounds. Here we have investigated the time framework of corals such as Lophelia pertusa and Madrepora oculata on five different mound settings of the eastern North Atlantic (on Rockall Bank and in Porcupine Seabight), sampled at variable depth and location (610-880 m water depth). We have found that the past 11 ka reflect a period generally favourable for coral development. We further determined local mound growth rates and identified mound surface erosion (framework collapse) during times of active coral framework construction. "Local" vertical mound growth rates vary between less than 5 cm ka(-1) and up to 220 cm ka(-1). We interpret... |
Tipo: Text |
Palavras-chave: Carbonate mound; Deep sea corals; U-series dating; Climate; Rockall Bank; Porcupine Seabight. |
Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00219/33060/31574.pdf |
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Gottschalk, Julia; Skinner, Luke C.; Lippold, Joerg; Vogel, Hendrik; Frank, Norbert; Jaccard, Samuel L.; Waelbroeck, Claire. |
Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a 'control valve' on ocean–atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air–sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and 14C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the... |
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Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00334/44544/44256.pdf |
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Tachikawa, Kazuyo; Arsouze, Thomas; Bayon, Germain; Bory, Aloys; Colin, Christophe; Dutay, Jean-claude; Frank, Norbert; Giraud, Xavier; Gourlan, Alexandra T.; Jeandel, Catherine; Lacan, Francois; Meynadier, Laure; Montagna, Paolo; Piotrowski, Alexander M.; Plancherel, Yves; Puceat, Emmanuelle; Roy-barman, Matthieu; Waelbroeck, Claire. |
Neodymium isotopic compositions (143Nd/144Nd or εNd) have been used as a tracer of water masses and lithogenic inputs to the ocean. To further evaluate the faithfulness of this tracer, we have updated a global seawater εNd database and combined it with hydrography parameters (temperature, salinity, nutrients and oxygen concentrations), carbon isotopic ratio and radiocarbon of dissolved inorganic carbon. Archive εNd data are also compiled for leachates, foraminiferal tests, deep-sea corals and fish teeth/debris from the Holocene period (< 10,000 years). At water depths ≥ 1500 m, property-property plots show clear correlations between seawater εNd and the other variables, suggesting that large-scale water mass mixing is a primary control of deepwater εNd... |
Tipo: Text |
Palavras-chave: Nd isotopes; Water mass tracer; Data compilation; Predicted seawater epsilon(Nd); Seawater-archive comparison. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00376/48768/49165.pdf |
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Dubois-dauphin, Quentin; Bonneau, Lucile; Colin, Christophe; Montero-serrano, Jean-carlos; Montagna, Paolo; Blamart, Dominique; Hebbeln, Dierk; Van Rooij, David; Pons-branchu, Edwige; Hemsing, Freya; Wefing, Anne-marie; Frank, Norbert. |
The Nd isotopic composition (εNd) of seawater and cold-water coral (CWC) samples from the Gulf of Cádiz and the Alboran Sea, at a depth of 280-827 m were investigated in order to constrain mid-depth water mass dynamics within the Gulf of Cádiz over the past 40 ka. εNd of glacial and Holocene CWC from the Alboran Sea and the northern Gulf of Cádiz 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 mid-depth waters from the Mediterranean Outflow Water (MOW; εNd ∼ -9.4) and Mediterranean Sea Water (MSW; εNd ∼ -9.9). In contrast, glacial εNd values for CWC collected at thermocline depth (550-827 m) in the southern Gulf of Cádiz display a higher average value... |
Tipo: Text |
Palavras-chave: Neodymium isotopes; Cold-water corals; Mediterranean outflow water; East Antarctic intermediate water; Mediterranean sea water; Gulf of Cadiz. |
Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00339/45047/44446.pdf |
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Registros recuperados: 11 | |
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