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Registros recuperados: 18 | |
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Piva, A; Asioli, A; Schneider, R; Trincardi, F; Andersen, N; Colmenero Hidalgo, E; Dennielou, Bernard; Flores, J; Vigliotti, L. |
[1] A multiproxy integrated chronological framework, based on oxygen and carbon stable isotope stratigraphy, biostratigraphy (foraminifera and nannoplankton bioevents and foraminifer assemblage-based climate cyclicity), magnetostratigraphy, sapropel stratigraphy, and C-14 AMS radiometric dates, has been achieved for borehole PRAD1-2, collected in 185.5 m water depth in the central Adriatic. This work was carried out within the European Community project Profiles across Mediterranean Sedimentary Systems (PROMESS1). The 71.2 m long borehole spans a time interval between late MIS 11 and MIS 1 (the last 370 ka), showing a chronological resolution of 500 and 250 years per cm during interglacial and glacial intervals, respectively. At present, this record is the... |
Tipo: Text |
Palavras-chave: Sapropel stratigraphy; Adriatic Sea; D O events; Foraminifera; Oxygen isotope stratigraphy; Late Quaternary. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3605.pdf |
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Mazuel, Aude; Sisavath, Emmanuelle; Babonneau, Nathalie; Jorry, Stephan; Bachelery, Patrick; Delacourt, Christophe. |
Recent marine geophysical surveys reveal the existence of well-developed volcaniclastic deep-sea fans around La Réunion Island, Indian Ocean. The Mafate turbidite complex, located in the northwestern part of the island, is a large sedimentary system formed by two coalescent-like volcaniclastic deep-sea fans: the Mafate fan and the Saint-Denis fan. They are both connected to terrestrial rivers supplying sediment produced by erosion on the island, particularly during austral summer cyclonic floods. Through the integration of marine geophysical data (including bathymetry, backscatter multibeam sounder images, TOBI side-scan sonar images and seismic reflection profiles) and piston cores, a submarine morpho-sedimentary map of the surface architecture of the... |
Tipo: Text |
Palavras-chave: Deep-sea fan; Turbidite; Volcaniclastic; Land-to-sea transfer; La Reunion Island; Late Quaternary. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00312/42273/41597.pdf |
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Matsu’ura, Tabito; Ikehara, Minoru; Ueno, Tatsuyuki. |
We investigated the deep-sea sedimentary sequence of core MD012422 corresponding to the last 350 ka (since marine isotopic stage, MIS 10) from off Shikoku Island, NW Pacific Ocean, and refined its tephrostratigraphy. We detected many tephras and cryptotephras and correlated them with terrestrial tephras on the basis of the major- and trace-element compositions of their glass shards. Then we cross-checked our results against the reported marine tephrostratigraphy in the NW Pacific area and assessed the relative timing of tephra eruptions and bioevents. Many widespread tephras and cryptotephras originated from the Kyushu volcanic zone (Kuju, Aso, Kakuto, Aira, Ata, and Kikai volcanoes/calderas), along with the Takayama-Ng1 tephra (Tky-Ng1) from Suiendani... |
Tipo: Text |
Palavras-chave: Late Quaternary; Deep-sea sediments; Tephra; Glass shard; Major-element composition; Trace-element composition; Oxygen isotopic stratigraphy; Calcareous biostratigraphy; North Pacific. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00681/79355/81861.pdf |
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Chen, Guocheng; Zheng, Hongbo; Li, Jianru; Xie, Xin; Me, Xi. |
High-resolution oxygen isotope stratigraphy of Core MD05-2901, which is located off eastern Vietnam in the western South China Sea (SCS), was established and indicated that the core spans a time period of the past 450 ka. Based on the bulk density, fractional porosity and lithogenic content of the sediments, terrigenous mass accumulation rate (TMAR) was obtained, which is 4.9-6.0 g cm(-2) ka(-1) on average during interglacial stages, higher than that during glacial stages, i.e. 1.9-5.0 g cm(-2) ka(-1), which is different from northern and southern SCS which show higher TMAR in glacial stages. By principle component analysis of grain size distribution of all the samples, two main control factors (F1 and F2) were obtained, which are responsible for about 80%... |
Tipo: Text |
Palavras-chave: South China Sea; Late Quaternary; Terrigenous sediments; Grain size; East Asian monsoon. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00207/31846/30290.pdf |
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Fierens, Ruth; Droz, Laurence; Toucanne, Samuel; Raisson, François; Jouet, Gwenael; Babonneau, Nathalie; Miramontes Garcia, Elda; Landurain, Steven; Jorry, Stephan. |
The morphology and present-day sediment distribution of the Zambezi turbidite system was investigated using new bathymetric and sub-bottom profiler data as part of the PAMELA research project. The Zambezi turbidite system is composed of two depositional systems: a channelized fan (the Zambezi Fan) and a semi-confined fan (in the lntermediate Basin). The Zambezi Fan includes the Zambezi Valley, which is deeply incised in the Mozambique Channel and is more than three times as large and deep as the great Tanzanian and North Atlantic Mid-Ocean channels. The erosion in the Zambezi Valley is evidenced by its V-shaped morphology and the existence of a U-shaped thalweg affected by several generations of incisions. Based on echo facies and cores from literature,... |
Tipo: Text |
Palavras-chave: Zambezi turbidite system; Late Quaternary; Multibeam bathymetry; Sub-bottom seismic profiles. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00483/59425/62240.pdf |
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Giunta, Simona; Morigi, Caterina; Negri, Alessandra; Guichard, Francois; Lericolais, Gilles. |
In this study, detailed micropaleontological analyses were carried out on 270 samples from eight piston cores collected in the Black Sea. The primary goal was to elucidate the Late Quaternary evolution of the Black Sea, specifically to refine its biostratigraphy and to explore the Holocene paleoenvironmental changes. Three intervals were recognized in all the cores studied, irrespective of whether they were from the basin or the shelf. These intervals are characterized, from old to young, by the spotty occurrence, the presence and the local acme of Emiliania huxleyi respectively. Moreover, the species Braarudosphaera bigelowii is, in contrast to the younger units, absent in the oldest unit. The co-occurrence of the two marine species E. huxleyi and B.... |
Tipo: Text |
Palavras-chave: Stratigraphy; Late Quaternary; Black Sea; Calcareous nannoplankton. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2674.pdf |
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Sisavath, Emmanuelle; Mazuel, Aude; Jorry, Stephan; Babonneau, Nathalie; Bachelery, Patrick; De Voogd, Beatrice; Salpin, Marie; Emmanuel, Laurent; Beaufort, Luc; Toucanne, Samuel. |
The present study focused on turbidite sedimentation in the Cilaos turbidite system, a volcaniclastic deep-sea fan recently recognized offshore La Réunion Island. A set of piston cores was collected in order to establish the stratigraphy of this fan and to examine the processes controlling the turbidite sedimentation off the Cilaos cirque (Piton des Neiges volcanic massif) over the last climatic cycle. Two main phases of turbidite activity were identified, during the ca 140–127 ka and 30–0 ka periods, coinciding with the two last glacial–interglacial transitions (i.e., Terminations II and I). In addition to changes in climate and eustatic sea-level, these periods coincide with a low effusive volcanic activity of the Piton des Neiges volcano. The high... |
Tipo: Text |
Palavras-chave: Turbidites; La Reunion Island; Indian Ocean; Late Quaternary; Volcaniclastic system. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00105/21659/19383.pdf |
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Popescu, Irina; Lericolais, Gilles; Panin, N; Wong, H; Droz, Laurence. |
Analysis of new high-resolution seismic-reflection profiles, chirp profiles and previously published sidescan data, together with piston cores on the Danube Fan provide new insight into the recent sedimentation processes in the deep northwestern Black Sea.The latest channel-levee system on the Danube Fan developed probably during the Neoeuxinian lowstand (oxygene isotope stage 2) in a semi-freshwater basin with a water level about 100 m lower than today. Sediment supplied by the Danube was transported to the deep basin through the Viteaz Canyon, which was directly connected to the leveed channel of this system on the middle slope. Channel avulsion was common in the middle fan, as indicated by four main phases of bifurcation. Each phase developed after the... |
Tipo: Text |
Palavras-chave: High resolution seismic; Late Quaternary; Avulsion; Deep sea fan; Black Sea. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-474.pdf |
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Chen, Yy; Chen, Mt; Fang, Ts. |
Ultrahigh resolution records of carbonate and organic carbon concentrations from core MD972148 (19 degrees 47.804'N 117 degrees 32.56'E; water depth 2830 m) provide information on glacial-interglacial as well as millennial to centennial scale variability in the production of biogenic sediments in the northern slope of the South China Sea (SCS) over the past 150,000 years. A preliminary age model of this record is estimated using a biostratigraphic datum of Globigerinoides ruber (pink) and the relationship of carbonate concentrations and partial derivative(18)O of planktonic foraminifers shown in previous SCS records. The downcore patterns in this record show that the carbonate concentration maxima correspond to interglacial times and minima correspond to... |
Tipo: Text |
Palavras-chave: Paleoceanography; Late Quaternary; Carbonate sedimentology; South China Sea. |
Ano: 1999 |
URL: https://archimer.ifremer.fr/doc/00239/35072/34559.pdf |
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Kemp, Justine; Hope, Geoff. |
Regional changes in vegetation and environment in the last 16 ka have been reconstructed from Micalong Swamp and Willigobung Swamp (35 degrees S) on the western Southern Tablelands of New South Wales (NSW). Micalong Swamp lies at 980m above sea level (a.s.l.), which is close to the subalpine treeline at this latitude. Willigobung Swamp (780m a.s.l.) approaches the modern ecotone between dry and wet montane forest formations. The sites are sensitive to shifts in temperature and precipitation and are the first reported pollen records from the western montane slopes of NSW. A radiocarbon-based chronology indicates that Micalong Swamp was a swampy, gravel floodplain surrounded by alpine grassland before 16.1 ka. Subalpine woodland may have become established... |
Tipo: Text |
Palavras-chave: Charcoal; Fen peatlands; Late Quaternary; Pollen; South-eastern Australia; Vegetation history. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00289/40059/39334.pdf |
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Chang, Yp; Chang, Cc; Wang, Lw; Chen, Mt; Wang, Ch; Yu, Ef. |
A high-resolution (similar to 4 - 5cm/kyr) giant piston core record (MD962085) retrieved during an IMAGES II - NAUSICAA cruise from the continental slope of the southeast Atlantic Ocean reveal striking variations in planktonic foraminifer faunal abundances and sea-surface temperatures (SST) during the past 400,000 years. The location and high-quality sedimentary record of the core provide a good opportunity to assess changes in the intensity and position of the Benguela Current System and the Subtropical Convergence, two key features of the ocean-climate system in the south Atlantic. This record can be also used to evaluate the possible influence of Agulhas Current from the throughflow of the Indian Ocean into the South Atlantic. The planktonic foraminifer... |
Tipo: Text |
Palavras-chave: Paleoceanography; Late Quaternary; Micropaleontology; South Atlantic. |
Ano: 1999 |
URL: https://archimer.ifremer.fr/doc/00239/35070/34563.pdf |
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Registros recuperados: 18 | |
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