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Registros recuperados: 13 | |
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Chen, Quan; Liu, Zhifei; Kissel, Catherine. |
The East Asian summer monsoon controls the climatic regime of an extended region through temperature and precipitation changes. As the East Asian summer monsoon is primarily driven by the northern hemisphere summer insolation, such meteorological variables are expected to significantly change on the orbital timescale, influencing the composition of terrestrial sediments in terms of both mineralogy and geochemistry. Here we present clay mineralogy and major element composition of Core MD12-3432 retrieved from the northern South China Sea, and we investigate their relationship with the East Asian summer monsoon evolution over the last 400 ka. The variability of smectite/(illite + chlorite) ratio presents a predominant precession periodicity, synchronous with... |
Tipo: Text |
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Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00371/48247/48383.pdf |
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Dokken, Trond M.; Nisancioglu, Kerim H.; Li, Camille; Battisti, David S.; Kissel, Catherine. |
Dansgaard-Oeschger (D-O) cycles are the most dramatic, frequent, and wide-reaching abrupt climate changes in the geologic record. On Greenland, D-O cycles are characterized by an abrupt warming of 105 degrees C from a cold stadial to a warm interstadial phase, followed by gradual cooling before a rapid return to stadial conditions. The mechanisms responsible for these millennial cycles are not fully understood but are widely thought to involve abrupt changes in Atlantic Meridional Overturning Circulation due to freshwater perturbations. Here we present a new, high-resolution multiproxy marine sediment core monitoring changes in the warm Atlantic inflow to the Nordic seas as well as in local sea ice cover and influx of ice-rafted debris. In contrast to... |
Tipo: Text |
Palavras-chave: D-O cycles; Nordic seas; Marine sediment core; Greenland ice core; Abrupt changes; Sea ice. |
Ano: 2013 |
URL: https://archimer.ifremer.fr/doc/00264/37490/35779.pdf |
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Piret, Loic; Bertrand, Sebastien; Kissel, Catherine; De Pol-holz, Ricardo; Tamayo Hernando, Alvaro; Van Daele, Maarten. |
Megaturbidites have been the focus of many paleoseismic and paleoenvironmental studies because they can provide evidence for catastrophic and/or hazardous events with potentially major environmental implications. During a recent research cruise in Baker Fjord, Chile (47°54′S–74°30′W), a megaturbidite was described between the Northern and Southern Patagonian Icefields. Here, we aim to determine the depositional processes of the megaturbidite and identify its origin. Based on the turbidite's location, a possible origin was the early Holocene drainage of paleo-lake General Carrera, which was recently proposed in the literature as having produced a Glacial Lake Outburst Flood (GLOF) that drained through Baker Fjord. Due to the fjord's location in a subduction... |
Tipo: Text |
Palavras-chave: Turbidite; Sediment provenance; Patagonia; Holocene; Earthquake. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00425/53700/54551.pdf |
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Aracena, Claudia; Kilian, Rolf; Lange, Carina B.; Bertrand, Sebastien; Lamy, Frank; Arz, Helge W.; De Pol-holz, Ricardo; Baeza, Oscar; Pantoja, Silvio; Kissel, Catherine. |
One of the most important factors controlling fjord primary production in southernmost Patagonia is the variability in the thermohaline structure of the water column. In the present-day environment, thermal stratification is mostly related to freshwater input and in particular, the seasonal melting of glaciers. Here we assess whether this relation between fjord productivity and freshwater input holds true for the Holocene, using a sediment record from the central basin of the Strait of Magellan (core MD07-3132, 53°44.17′S; 70°19.03′W, 301 m). Our approach relies on a proxy-based reconstruction of fjord sea surface temperature (alkenone SST), paleosalinity, freshwater input, and paleoproductivity. The results indicate that, during the early Holocene, the... |
Tipo: Text |
Palavras-chave: Strait of Magellan; Holocene; Paleoproductivity; Thermohaline conditions. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00294/40518/39325.pdf |
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Bolliet, Timothe; Holbourn, Ann; Kuhnt, Wolfgang; Laj, Carlo; Kissel, Catherine; Beaufort, Luc; Kienast, Markus; Andersen, Nils; Garbe-schoenberg, Dieter. |
We present sea surface, upper thermocline, and benthic delta O-18 data, as well as temperature and paleoproductivity proxy data, from the International Marine Global Change Study Program (IMAGES) Core MD06-3067 (6 degrees 31' N, 126 degrees 30' E, 1575 m water depth), located in the western equatorial Pacific Ocean within the flow path of the Mindanao Current. Our records reveal considerable glacial-interglacial and suborbital variability in the Mindanao Dome upwelling over the last 160 kyr. Dome activity generally intensified during glacial intervals resulting in cooler thermocline waters, whereas it substantially declined during interglacials, in particular in the early Holocene and early marine oxygen isotope stage (MIS) 5e, when upwelling waters did... |
Tipo: Text |
Palavras-chave: Mindanao Dome; East Asian monsoon; Oceanic circulation. |
Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00213/32472/30924.pdf |
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Kissel, Catherine; Laj, Carlo; Kienast, Markus; Bolliet, Timothe; Holbourn, Ann; Hill, Paul; Kuhnt, Wolfgang; Braconnot, Pascale. |
Magnetic and grain size properties of a sediment core located in the western equatorial Pacific, off the southeastern tip of the Philippine island of Mindanao, are presented in an effort to reconstruct past changes in the East Asian Monsoon and deep ocean circulation during the last 160 kyrs. The sedimentary concentration of magnetic particles, interpreted to reflect past changes in runoff from Mindanao, varies almost in antiphase with Northern Hemisphere insolation. This suggests that precipitation was lower in the western equatorial Pacific region during boreal insolation maxima and thus corroborates model results showing opposing trends in precipitation between land and the marine realm there. Variations in the grain size distribution of the inorganic... |
Tipo: Text |
Palavras-chave: North atlantic; Grain size; Water; Core; Mindanao; Paleoceanography; Susceptibility; Anisotropy; Remanence; Iceland. |
Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00207/31854/30262.pdf |
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Irvali, Nil; Ninnemann, Ulysses S.; Galaasen, Eirik V.; Rosenthal, Yair; Kroon, Dick; Oppo, Delia W.; Kleiven, Helga F.; Darling, Kate F.; Kissel, Catherine. |
At the peak of the previous interglacial period, North Atlantic and subpolar climate shared many features in common with projections of our future climate, including warmer-than-present conditions and a diminished Greenland Ice Sheet (GIS). Here we portray changes in North Atlantic hydrography linked with Greenland climate during Marine Isotope Stage (MIS) 5e using (sub)centennially sampled records of planktonic foraminiferal isotopes and assemblage counts and ice-rafted debris counts, as well as modern analog technique and Mg/Ca-based paleothermometry. We use the core MD03-2664 recovered from a high accumulation rate site (similar to 34 cm/kyr) on the Eirik sediment drift (57 degrees 26.34'N, 48 degrees 36.35'W). The results indicate that surface waters... |
Tipo: Text |
Palavras-chave: Eirik Drift; MIS 5e; North Atlantic; Last interglacial; Multiproxy. |
Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00139/25046/23154.pdf |
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Wary, Melanie; Eynaud, Frederique; Swingedouw, Didier; Masson-delmotte, Valerie; Matthiessen, Jens; Kissel, Catherine; Zumaque, Jena; Rossignol, Linda; Jouzel, Jean. |
Dansgaard-Oeschger oscillations constitute one of the most enigmatic features of the last glacial cycle. Their cold atmospheric phases have been commonly associated with cold sea-surface temperatures and expansion of sea ice in the North Atlantic and adjacent seas. Here, based on dinocyst analyses from the 48-30 ka interval of four sediment cores from the northern Northeast Atlantic and southern Norwegian Sea, we provide direct and quantitative evidence of a regional paradoxical seesaw pattern: cold Greenland and North Atlantic phases coincide with warmer sea-surface conditions and shorter seasonal sea-ice cover durations in the Norwegian Sea as compared to warm phases. Combined with additional palaeorecords and multi-model hosing simulations, our results... |
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Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00420/53149/55328.pdf |
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Wils, Katleen; Daele, Maarten Van; Kissel, Catherine; Moernaut, Jasper; Schmidt, Sabine; Siani, Giuseppe; Lastras, Galderic. |
Grain‐size analysis and end‐member modelling of a long sediment core from Aysén Fjord (southern Chile) allows to identify over 25 seismo‐turbidites in the last 9000 years. Considering the shaking intensities required to trigger these turbidites (V½‐VI½), the majority can be related to megathrust earthquakes. Multiple studies in south‐central Chile have aimed at finding traces of giant, tsunamigenic megathrust earthquakes leading to the current 5500‐year‐long paleoseismological record of the Valdivia Segment. However, none of these cover the southern third of the segment. Aysén Fjord allows to fill this data gap and presents the first, crucial paleoseismic data to demonstrate that the 1960 event was not unique for the Valdivia Segment, yielding a recurrence... |
Tipo: Text |
Palavras-chave: Megathrust earthquakes; Turbidite paleoseismology; Valdivia segment; South-central Chile; Variable rupture mode. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00646/75832/76820.pdf |
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Peral, Marion; Daeron, Mathieu; Blamart, Dominique; Bassinot, Franck; Dewilde, Fabien; Smialkowski, Nicolas; Isguder, Gulay; Bonnin, Jerome; Jorissen, Frans; Kissel, Catherine; Michel, Elisabeth; Vazquez Riveiros, Natalia; Waelbroeck, Claire. |
Accurate reconstruction of past ocean temperatures is of critical importance to paleoclimatology. Carbonate clumped isotope thermometry (“Δ47”) is a relatively recent technique based on the strong relationship between calcification temperature and the statistical excess of 13C-18O bonds in carbonates. Its application to foraminifera holds great scientific potential, particularly because Δ47 paleotemperature reconstructions do not require assumptions regarding the 18O composition of seawater. However there are still relatively few published observations investigating the potential influence of parameters such as salinity or foraminiferal size and species. We present a new calibration data set based on 234 replicate analyses of 9 planktonic and 2 benthic... |
Tipo: Text |
Palavras-chave: Carbonate clumped isotopes; Foraminifera; Paleothermometry. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56134/57676.pdf |
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Registros recuperados: 13 | |
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