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| Registros recuperados: 64 | |
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| Courgeon, Simon; Bachelery, Patrick; Jouet, Gwenael; Jorry, Stephan; Bou, Esther; Boudagher-fadel, Marcelle K.; Revillon, Sidonie; Camoin, Gilbert; Poli, Emmanuelle. |
| The offshore branch of the East African Rift System (EARS) has developed during late Cenozoic time along the eastern Africa continental margin. While Neogene–Pleistocene extensional tectonic deformation has been evidenced along the northern segment of the Davie Ridge, the spatial extent of deformation further south remains poorly documented. Based on recent and various oceanographic data sets (bathymetric surveys, dredge samples and seismic profiles), our study highlights active normal faulting, modern east–west extensional tectonic deformation and Late Cenozoic alkaline volcanism at the Sakalaves Seamounts (18°S, Davie Ridge) that seem tightly linked to the offshore EARS development. In parallel, rift‐related tectonic subsidence appears responsible for... |
| Tipo: Text |
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| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00452/56344/57934.pdf |
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| Leroux, Estelle; Counts, J.; Jorry, Stephan; Jouet, Gwenael; Révillon, Sidonie; Boudagher-fadel, M.k.; Courgeon, S.; Berthod, C.; Ruffet, G.; Bachèlery, P.; Grenard-grand, E.. |
| Little is known about the geological history of the Glorieuses seamount including basic information about its age and origin related to the regional evolution of the southern tip of the Somali Basin. This study focused on describing and reconstructing the long-term stratigraphic evolution of the Glorieuses seamount (SW Indian Ocean) to identify the mechanisms that have occurred through time to finally shape the emerged modern islands. Distinct terrace levels, currently submerged along the flanks of the seamount and surrounding seamounts, have already been interpreted as resulting from successive carbonate development and back-stepping episodes over the last 62 Myr. New isotopic and biostratigraphic dating on the flanks of the seamount, coupled with... |
| Tipo: Text |
Palavras-chave: Glorieuses seamount; Somali Basin; Seismic stratigraphy; Tectonics; Vertical movement (uplift and subsidence); Volcanism; Shallow-water carbonate platform; Ar-40/Ar-39. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00628/73965/73324.pdf |
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| Bassetti, Maria-angela; Berne, Serge; Jouet, Gwenael; Taviani, M; Dennielou, Bernard; Flores, J; Gaillot, Arnaud; Gelfort, R; Lafuerza, S; Sultan, Nabil. |
| Thick forced regressive units on the wide continental shelf of the Gulf of Lions (western Mediterranean) recorded the composite effect of sea level changes during the Quaternary. They are mostly composed of coastal siliciclastic and bioclastic wedges showing clinoform geometry. These deposits have been intensively explored through high-resolution seismic investigations, but only recently it was possible to ground truth seismic interpretations, based on a long (100 m) borehole that crossed the succession and recovered a large part of the mainly sandy deposits (similar to 84% recovery). A multiproxy analysis of the sedimentary succession shows that (1) the stratal architecture of the shelf margin is defined by major bounding surfaces that are polygenic... |
| Tipo: Text |
Palavras-chave: Paleoclimate; Mediterranean; Quaternary; Shoreface. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4929.pdf |
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| Angue Minto’o, Charlie Morelle; Bassetti, Maria-angela; Toucanne, Samuel; Jouet, Gwenael. |
| The study of Quaternary sediments covering the last 550 kyr from the borehole GDEC-4-2, East-Corsica basin, was performed through the study of benthic meiofaunal assemblages (ostracoda and benthic foraminifera) whose distribution responds to climate changes, and glacial–interglacial variability in particular. The interglacial ostracod group is mainly composed of the Argilloecia acuminata, Cytheropteron alatum, Henryhowella sp., Polycope sp. and Cytherella sp., which indicate an enhanced surface productivity and possibly high bottom water temperature during these warm intervals. Benthic foraminifera, such as Hoeglundina elegans, Sigmoilopsis schlumbergeri, Bigenerina nodosaria and Hyalinea balthica are predominant during interglacial periods and also show... |
| Tipo: Text |
Palavras-chave: Est-Corse; Ostracode; Foraminifère benthique; Groupe allochtone; East-Corsica; Ostracoda; Benthic foraminifera; Allochthonous group. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00313/42426/42030.pdf |
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| Courgeon, Simon; Jorry, Stephan; Jouet, Gwenael; Camoin, G.; Boudagher-fadel, M. K.; Bachelery, P.; Caline, B.; Boichard, R.; Revillon, Sidonie; Thomas, Yannick; Thereau, Estelle; Guerin, Charline. |
| Understanding the impact of tectonic activity and volcanism on long-term (i.e. millions years) evolution of shallow-water carbonate platforms represents a major issue for both industrial and academic perspectives. The southern central Mozambique Channel is characterized by a 100 km-long volcanic ridge hosting two guyots (the Hall and Jaguar banks) and a modern atoll (Bassas da India) fringed by a large terrace. Dredge sampling, geophysical acquisitions and submarines videos carried out during recent oceanographic cruises revealed that submarine flat-top seamounts correspond to karstified and drowned shallow-water carbonate platforms largely covered by volcanic material and structured by a dense network of normal faults. Microfacies and well-constrained... |
| Tipo: Text |
Palavras-chave: Carbonate platform; Drowning; Volcanism; Tectonic; Mozambique Channel. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00384/49554/50048.pdf |
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| Dennielou, Bernard; Jallet, Laurent; Sultan, Nabil; Jouet, Gwenael; Giresse, Pierre; Voisset, Michel; Berne, Serge. |
| Emplacement of post-glacial turbidites is commonly controlled by rapid changes in sea level or by seismicity. On the continental rise of the Gulf of Lions (Western Mediterranean), an aseismic area, we identified turbiditic beds deposited during the rising stage and highstand of sea level. Swath bathymetry, sediment cores, in situ Cone Penetrating Tests (CPTU), heavy mineral associations and radiocarbon dating determined the source, composition, distribution and age of the turbiditic beds. Turbidites are composed of homogeneous to positively graded silts to medium sand with quartz (up to 90%), shell debris and shelfal benthic faunas. Their distribution on the sea floor is very patchy and controlled by abundant inherited erosional bedforms. Their source is... |
| Tipo: Text |
Palavras-chave: Holocene; Late Pleistocene; Sea level; Turbidites; Sand; Outer shelf; Canyons. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6316.pdf |
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| Lombo Tombo, Swesslath; Dennielou, Bernard; Berne, Serge; Bassetti, Maria-angela; Toucanne, Samuel; Jorry, Stephan; Jouet, Gwenael; Fontanier, Christophe. |
| The timing, routing and processes of sediment transfer from the continents to the oceans at millennial time-scale are still largely unknown. The potential of turbidite systems (dominantly deposited during sea-level lowstands) to record global or regional environmental fluctuations is usually under-exploited because of the difficulty to obtain robust chronostratigraphic constraints in turbiditic deposits, and therefore to tie changes in sedimentary processes to environmental fluctuations. We were able to obtain a millennial-scale chronostratigraphy based on oxygen isotopes of the scarce foraminifera preserved in turbiditic deposits of the Rhone Turbidite System within the Western Mediterranean. Our results show that 1) objective criteria can be defined for... |
| Tipo: Text |
Palavras-chave: Rhone Turbidite System; Turbidites; Hyperpycnite; Sea level; Last Glacial Maximum; Western Mediterranean. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00266/37712/35730.pdf |
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| Lafuerza, S.; Frigola, J.; Canals, M.; Jouet, Gwenael; Bassetti, Maria-angela; Sultan, Nabil; Berne, Serge. |
| We show the results provided by piezocone tests in determining the stratigraphic profile and the soil classification of two drilling sites in the outer shelf and the upper slope of the Gulf of Lion, PRGL2 and PRGL1, respectively. Correlations with grain-size data indicate that sleeve friction can be used for profiling fine-grained sediments (site PRGL1), whereas cone tip resistance is the most adequate for sequences made of alternations of coarse- and fine-grained intervals (site PRGL2). Normalized cone resistance and friction ratio proved to be also appropriate for soil stratigraphy as it depicts trends in the coarse fraction of the tested soil. Silts and clays present in similar proportions at site PRGL1 responded to piezocone testing as pure clays... |
| Tipo: Text |
Palavras-chave: Gulf of Lion; Soil classification; Stratigraphy; Piezocone. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6121.pdf |
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| Miramontes, Elda; Jorry, Stephan; Jouet, Gwenael; Counts, John; Courgeon, Simon; Roy, Philippe; Guerin, Charline; Hernández-molina, F. Javier. |
| Subaqueous sand dunes are common bedforms on continental shelves dominated by tidal and geostrophic currents. However, much less is known about sand dunes in deep‐marine settings that are affected by strong bottom currents. In this study, dune fields were identified on drowned isolated carbonate platforms in the Mozambique Channel (south‐west Indian Ocean). The acquired data include multibeam bathymetry, multi‐channel high‐resolution seismic reflection data, sea floor imagery, a sediment sample and current measurements from a moored current meter and hull‐mounted acoustic Doppler current profiler. The dunes are located at water depths ranging from 200 to 600 m on the slope terraces of a modern atoll (Bassas da India Atoll) and within small depressions... |
| Tipo: Text |
Palavras-chave: Bedform; Bottom currents; Contourite; Deep-marine environment; Eddy; Geostrophic current; Oceanic circulation. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00472/58418/60989.pdf |
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| Miramontes Garcia, Elda; Jouet, Gwenael; Cattaneo, Antonio; Thereau, Estelle; Guerin, Charline; Jorry, Stephan; Droz, Laurence. |
| The upper slopes of continental margins are very energetic areas where nepheloid layers are often observed. Multibeam bathymetry, sub-bottom profiler and multi-channel highresolution seismic reflection data acquired during the PAMELA-MOZ04 survey in the Mozambique Channel revealed the presence of sand dunes on the upper slope at 120-250 m water depth. The dunes migrate upslope and their crests are oblique to the contours. They are medium to large dunes, with wavelengths between 20 and 150 m and heights between 0.15 and 1.50 m, and their size decreases upslope. Seismic reflection data of the water column show internal solitary waves travelling offshore in the depth range of the dune field. The formation of the dune field could be related to the interaction... |
| Tipo: Text |
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| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00499/61049/64460.pdf |
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| Minto'O, Charlie Morelle Angue; Silva Jacinto, Ricardo; Bassetti, Maria-angela; Jouet, Gwenael. |
| In this study, the model H(i) = 109.6103 + C1 × F1(i) + C2 × F2(i) + … + C33 × F33(i) obtained from depth modelling based on 33 recent benthic foraminifer species distribution, has been applied to the fossil benthic foraminifers from the borehole GDEC-4-2 drilled at a water depth of 491 m, in the East-Corsica basin, covering the last 550,000 years. The obtained variations of the paleo-depths show a medium correlation with the oscillations of the relative sea level and also with the fluctuations of the oxygen isotopic ratio (δ18O G. bulloides and δ18O C. pachyderma–C. wuellerstorfi). This newly developed transfer function is accompanied by an error margin of ± 86 m, suggesting that this model will probably be more suitable for a time scale of the order of a... |
| Tipo: Text |
Palavras-chave: Benthic foraminifers; East-Corsica basin; Paleo-depths; Transfer function. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00463/57477/64237.pdf |
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| Gregoire, Gwendoline; Le Roy, Pascal; Ehrhold, Axel; Jouet, Gwenael; Garlan, Thierry. |
| This study details the sedimentary infilling of an original tidal-dominated estuary system during the final stage of the last marine transgression. The Bay of Brest is confined and connects the rivers Elorn and Aulne, to the sea of Iroise by a narrow strait encasing a well preserved paleo-channel. The compilation of high- and very-high-resolution bathymetric and seismic data, constrained by sediments datations, allows us to classify the paleo-morphology of the bay into three stepped domains: the paleo-valley floor surrounded by fluvial terraces, the central plateau, and the shallow embayments. Taking into account the main factors controlling the infilling, including sea-level rise, substratum morphology, and hydrodynamics, the stratigraphic scheme of the... |
| Tipo: Text |
Palavras-chave: Tide-dominated estuary; Incised-valley; Holocene infill; Seismic stratigraphy; Estuarine processes; Bay of Brest. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00358/46968/46883.pdf |
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| Jouet, Gwenael; Gaudin, Mathieu; Bassetti, Maria-angela; Berne, Serge; Rabineau, Marina; Dennielou, Bernard; Sierro, F; Flores, J; Taviani, M. |
| The Rhône deltaic margin (NW Mediterranean) was under the influence of a very high sedimentation flux during the last climatic cycle, because of the vicinity of major fluvial systems that fed the outer shelf during the glacial period and the inner shelf during the deglacial period. The two areas provide a complete sedimentary record of depositional events from 130 cal. kyr BP to present. This sequence represents the sedimentary expression of the glacial/interglacial cycle (100 kyr cyclicity) within the Late Quaternary succession [1]. [Extract] |
| Tipo: Text |
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| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-6152.pdf |
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| Sweet, Michael L.; Gaillot, Gwladys T.; Jouet, Gwenael; Rittenour, Tammy M.; Toucanne, Samuel; Marsset, Tania; Blum, Michael D.. |
| How and when sediment moves from shallow marine to deep-water environments is an important and poorly understood control on basin-scale sediment dispersal patterns, the evolution of continental margins, and hydrocarbon exploration in deep-water basins. The Golo River (Eastern Corsica, France), its delta, canyons, and fans provide a unique opportunity to study sediment routing from source to sink in a relatively compact depositional system. We studied this system using an array of high-frequency seismic data, multi-beam bathymetry, and five cores for lithology and age control. Movement of sediment to deep water was controlled by interactions between the Golo River, the Golo Delta, and shelf-penetrating submarine canyons. Sediment moved to deep water when... |
| Tipo: Text |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00589/70154/68234.pdf |
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| Miramontes Garcia, Elda; Garreau, Pierre; Caillaud, Matthieu; Jouet, Gwenael; Pellen, Romain; Hernández-molina, F. Javier; Clare, Michael A.; Cattaneo, Antonio. |
| Contourites are common morphological features along continental margins where currents encounter the seafloor. They can provide long-term archives of palaeoceanography, may be prone to sediment instability, and can have a great potential for hydrocarbon exploration. Despite their importance and increasingly recognised ubiquitous occurrence worldwide, the link between oceanographic processes and contourite features is poorly constrained. In particular, it is unclear under which specific conditions sediments are mobilised, modified and deposited by bottom currents. Here, we aim to determine key bottom current characteristics (velocity and bottom shear stress) affecting contourite deposition, by assuming that recent oceanographic regimes may be extended back... |
| Tipo: Text |
Palavras-chave: Sediment drift; Erosion; Oceanic circulation; Bottom shear stress. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00483/59426/62241.pdf |
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| Cattaneo, Antonio; Badhani, Shray; Caradonna, Cristina; Bellucci, Massimo; Leroux, Estelle; Babonneau, Nathalie; Garziglia, Sebastien; Poort, Jeffrey; Akhmanov, Grigorii G.; Bayon, Germain; Dennielou, Bernard; Jouet, Gwenael; Migeon, Sebastien; Rabineau, Marina; Droz, Laurence; Clare, Michael. |
| Megabeds are thick sedimentary layers extending over thousands square kilometres in deep sea basins and are thought to result from large slope failures triggered by major external events. Such deposits have been found in at least three areas of the Mediterranean Sea. Although their discovery dates back to the early 1980s, many questions remain, concerning their initiation, source area, extent, and the nature of their emplacement. One of the largest previously documented megabeds was emplaced during the Last Glacial Maximum across the Balearic Abyssal Plain with a thickness of 8-10 m in water depths of up to 2800 m. New 3.5 kHz sub-bottom profiles and sediment cores provide greater constraint on the lateral variability of the megabed and allow to map it... |
| Tipo: Text |
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| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00614/72597/71595.pdf |
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| Prat, Sophie; Jorry, Stephan; Jouet, Gwenael; Le Roy, Pascal; Camoin, Gilbert; Vella, Claude; Caline, Bruno. |
| Améliorer nos connaissances sur la distribution des sédiments carbonatés dans les systèmes récifaux actuels sert à définir des analogues afin de mieux comprendre les réservoirs à hydrocarbures exploités dans les formations récifales fossiles. Bien que le rôle des changements du niveau marin, de la tectonique et de la sédimentation sur la dynamique et l'évolution des plates-formes carbonatés tropicales ait été largement étudié, la variabilité sédimentaire et les facteurs qui contrôlent cette hétérogénéité sont moins bien connus. Quelques études illustrent bien cette répartition des sédiments au sein des plates-formes carbonatées actuelles (Purdy et Gischler, 2003; Thudhope et al., 1985; Maxwell, 1973), mais il existe peu de cas étudiés dans l'océan Indien.... |
| Tipo: Text |
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| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00202/31281/29688.pdf |
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| Registros recuperados: 64 | |
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