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| Registros recuperados: 33 | |
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| Lastras, Galderic; Canals, M; Amblas, D; Ivanov, M; Dennielou, Bernard; Droz, Laurence; Akhmetzhanov, A. |
| After obtaining full-coverage swath bathymetry data in 1995 and very high-resolution acoustic profiles in 2002, four slides at the Balearic Margin of the Eivissa Channel in the western Mediterranean Sea were revisited in 2004 when side-scan sonar data were collected using a MAK-1M deep-towed acoustic system. These new findings, higher in resolution than those for the swath bathymetry, show two main features previously undetected within these submarine landslides: (1) a series of step-forming inclined and detached slabs oriented perpendicular to the slide movement and located in the uppermost part of the slides, and (2) arcuate regular positive ridges oriented also normal to the slide movement and located in the depositional lobes of some of the slides. The... |
| Tipo: Text |
Palavras-chave: Morphology; Bathymetry; Slides; Mediterranean sea; Eivissa channel. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2087.pdf |
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| Badhani, Shray; Cattaneo, Antonio; Dennielou, Bernard; Leroux, Estelle; Colin, Florent; Thomas, Yannick; Jouet, Gwenael; Rabineau, Marina; Droz, Laurence. |
| The Gulf of Lions (NW Mediterranean Sea) is a SW-NE oriented passive continental margin formed since the Oligocene. It presents small to large scale mass movement features suggesting a long history of seafloor instability. Of particular interest are the two surficial large mass-transport deposits along the Rhone turbiditic levee, known as the Rhone Eastern and Western Mass-Transport Deposits (REMTD and RWMTD). With the help of the recently acquired multi-beam bathymetric, sub-bottom profiler, high-resolution seismic and sedimentological data, we investigate the morphology, timing, kinematics, and possible triggering mechanisms of the source area of the REMTD, which we refer to as the Eastern Rhone Interfluve Slide (ERIS). ERIS has an estimated run-out... |
| Tipo: Text |
Palavras-chave: Submarine landslide; Mass transport deposits; Gulf of Lions; Western Mediterranean; Turbiditic levees. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00592/70396/68480.pdf |
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| Miramontes, Elda; Penven, Pierrick; Fierens, Ruth; Droz, Laurence; Toucanne, Samuel; Jorry, Stephan; Jouet, Gwenael; Pastor, Lucie; Silva Jacinto, Ricardo; Gaillot, Arnaud; Giraudeau, Jacques; Raisson, François. |
| Mixed turbidite-contourite systems can be found in oceans where bottom currents and turbidity currents interact. The Zambezi turbidite system, located in the Mozambique Channel (SW Indian Ocean), is one of the largest sedimentary systems in the world in length and area of the related catchments. The oceanic circulation in the Mozambique Channel is intense and complex, dominated by eddies flowing southwards and deep currents flowing northwards along the Mozambican margin. Current measurements obtained from moorings at 3400–4050 m water depth in the Zambezi and Tsiribihina valleys show periods of intense currents at the seafloor with peaks of 40–50 cm s−1 that last up to one month and are not related to turbidity currents. These strong bottom-current events... |
| Tipo: Text |
Palavras-chave: Contourite; Turbidity current; Mixed system; Oceanic circulation; Mooring; ADCP; ROMS model; Bedform. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00476/58743/61269.pdf |
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| Dennielou, Bernard; Jegou, I.; Droz, Laurence; Jouet, Gwenael; Cattaneo, Antonio; Berné, Serge; Aslanian, Daniel; Loubrieu, Benoit; Rabineau, Marina; Bermell, Sylvain. |
| In the Gulf of Lions (Western Mediterranean), the emplacement of a large (160 km3) Mass Transport Deposit, the Rhone Western Mass Transport Deposit (RWMTD), at the base of slope, aside the Rhone deep-sea fan between 1800 and 2700 m water depth, resulted in a major modification of the sediment routing by clogging a drainage network and blocking at the base of slope sediments that were previously routed into the Valencia channel and the Balearic abyssal plain. The RWMTD was sourced from sediments of the western flank of the Rhone upper fan and the adjacent base of slope. The mass transport deposit is characterized by a transparent seismic facies and sediment cores show that it is composed of a stiff laminated muddy lithofacies characteristic of the Rhone fan... |
| Tipo: Text |
Palavras-chave: Gulf of Lions; Ebro margin; Sediment routing; Rhone deep-sea fan; Canyon; Mass transport deposit; Turbidite. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00480/59175/61813.pdf |
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| Miramontes, Elda; Jouet, Gwenael; Thereau, Estelle; Bruno, Miguel; Penven, Pierrick; Guerin, Charline; Le Roy, Pascal; Droz, Laurence; Jorry, Stephan; Hernández‐molina, F. Javier; Thiéblemont, Antoine; Silva Jacinto, Ricardo; Cattaneo, Antonio. |
| Evidences of sedimentation affected by oceanic circulation, such as nepheloid layers and contourites are often observed along continental slopes. However, the oceanographic processes controlling sedimentation along continental margins remain poorly understood. Multibeam bathymetry and high‐resolution seismic reflection data revealed a contourite depositional system in the Mozambican upper continental slope composed of a contourite terrace (a surface with a gentle seaward slope dominated by erosion) and a plastered drift (a convex‐shape sedimentary deposit). A continuous alongslope channel and a field of sand dunes (mainly migrating upslope), formed during Holocene, were identified in the contourite terrace at the present seafloor. Seismic reflection data... |
| Tipo: Text |
Palavras-chave: Contourite; Sediment drift; Bedform; Sedimentary processes; Tide; Internal solitary waves; Bottom currents. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00605/71730/70205.pdf |
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| Leroux, Estelle; Rabineau, Marina; Aslanian, Daniel; Gorini, Christian; Molliex, Stephane; Bache, Francois; Robin, Cecile; Droz, Laurence; Moulin, Maryline; Poort, Jeffrey; Rubino, Jean-loup; Suc, Jean-pierre. |
| Basin-wide correlation of Messinian units and Plio-Quaternary chronostratigraphic markers (5.3 Ma, 2.6 Ma, 0.9 Ma and 0.45 Ma), the mapping of total sediment thickness and the determination of overall sedimentary volumes enabled us to provide a high-resolution quantitative history of sediment volumes for the last 6 Ma along the Gulf of Lions margin. The results point to (i) a dramatic increase in terrigenous sediment input during the Messinian Salinity Crisis. This increased sedimentation reflects enhanced regional fluvial erosion related to the dramatic fall of Mediterranean base-level. Stronger weathering due to a regional wetter climate probably also increased erosional fluxes. (ii) A sediment input three times higher during the Plio-Quaternary compared... |
| Tipo: Text |
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| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00310/42087/41520.pdf |
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| Loncke, L.; Droz, Laurence; Gaullier, V.; Basile, C.; Patriat, Martin; Roest, Walter. |
| The French Guiana transform margin and Demerara abyssal plain have been recently surveyed in the framework of the EXTRAPLAC French Program of extension of the continental shelf (Guyaplac survey, Ifremer-IFP-SHOM-IPEV). Based on the interpretation of some of the data collected during the Guyaplac survey (Simrad-EM12 multibeam bathymetric data, backscatter imagery, and 3.5 kHz profiles), the area can be divided into three morphostructural domains. (1) The western Guiana margin, including a part of the Demerara plateau, an important bathymetric relief prolonging the continental platform off Guiana and Surinam. This domain is bounded by (1a) the NWSE trending northern border of the Demerara plateau which appears quite steep and corresponds to a transform... |
| Tipo: Text |
Palavras-chave: Structural heritage; Fluids; Creeping; Transform margin; Slope instabilities. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6856.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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| Droz, Laurence; Dos Reis, A. T.; Rabineau, Marina; Berne, Serge; Bellaiche, G. |
| The Balearic Basin is a young basin composed of thick Plio-Quaternary sediments, including active gravity sedimentation. During the Quaternary, gravity processes deposited (1) turbidite systems, either as symmetrical fans (Petit-Rhone and Valencia fans) or asymmetrical ridges (Marseille-Planier, Grand- Rhone and Pyreneo-Languedocian ridges) and (2) several mass-transport deposits, indicating recurrent sedimentary failures of the margin. This paper synthesizes previous works and proposes a chronological sedimentary evolution for the basin. Except for the last 20 ka, the chronostratigraphy remains poorly constrained but should soon be established for the last 500 ka, based on the PROMESS1 drillings on the outer shelf of the Gulf of Lions, and hopefully for... |
| Tipo: Text |
Palavras-chave: Gulf of Lion; Quaternary evolution; Turbidity; Sedimentary system. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2171.pdf |
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| Dalibard, Mathieu; Popescu, Speranta-maria; Maley, Jean; Baudin, Francois; Melinte-dobrinescu, Mihaela-carmen; Pittet, Bernard; Marsset, Tania; Dennielou, Bernard; Droz, Laurence; Suc, Jean-pierre. |
| The essential characteristics of the vegetation dynamics of tropical Africa remain only partially known. This study assesses the succession of vegetation-types over Central Africa during the last two glacial/interglacial cycles. Analysis of core KZai 02, which contains pollen from the Zaire River watershed (latitudes 9°N-13°S), allows the investigation of long-term patterns of plant ecosystem development and their climatic causes. Core KZai 02 (18.20 m long) was recovered from 6°24.20′S/9°54.10′E in the uppermost axial edifice of the Zaire deep sea fan. The chronology of this sedimentary archive was established using nannofossils and correlations of pollen and total organic carbon signals with the nearby core GeoB1008. The pollen record indicates that: (i)... |
| Tipo: Text |
Palavras-chave: Central Africa; Climate; Environmental parameters; Late Pleistocene; Pollen; Vegetation dynamics. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00199/31031/29436.pdf |
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| Baudin, Francois; Martinez, Philippe; Dennielou, Bernard; Charlier, Karine; Marsset, Tania; Droz, Laurence; Rabouille, Christophe. |
| Geochemical data (total organic carbon-TOC content, δ13Corg, C:N, Rock-Eval analyses) were obtained on 150 core tops from the Angola basin, with a special focus on the Congo deep sea fan. Combined with the previously published data, the resulting dataset (322 stations) shows a good spatial and bathymetric representativeness. TOC content and δ13Corg maps of the Angola basin were generated using this enhanced dataset. The main difference in our map with previously published ones is the high terrestrial organic matter content observed downslope along the active turbidite channel of the Congo deep sea fan till the distal lobe complex near 5,000 m of water-depth. Interpretation of downslope trends in TOC content and organic matter composition indicates that... |
| Tipo: Text |
Palavras-chave: Organic matter; Recent sediments; South Atlantic Ocean; Turbidites. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00369/47974/47999.pdf |
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| Dennielou, Bernard; Droz, Laurence; Babonneau, Nathalie; Jacq, Celine; Bonnel, Cedric; Picot, Marie; Le Saout, Morgane; Saout, Yohan; Bez, Martine; Savoye, Bruno; Olu, Karine; Rabouille, Christophe. |
| The detailed structure and composition of turbiditic channel-mouth lobes is still largely unknown because they commonly lie at abyssal water depths, are very thin and are therefore beyond the resolution of hull-mound acoustic tools. The morphology, structure and composition of the Congo turbiditic channel-mouth lobe complex (90×40 km; 2525 km2) were investigated with hull-mounted swath bathymetry, air gun seismics, 3.5 kHz sub-bottom profiler, sediment piston cores and also with high-resolution multibeam bathymetry and video acquired with a Remote Operating Vehicle (ROV). The lobe complex lies 760 km off the Congo River mouth in the Angola abyssal plain between 4740 and 5030 m deep. It is active and is fed by turbidity currents that deposit several... |
| Tipo: Text |
Palavras-chave: Congo deep-sea fan; Lobe; Lobe complex; Channel; Channel-Lobe Transition Zone; Angola basin; Slump; Slide; Debrite; Turbidite; ROV; Bathymetry; Seismic; Sediment core. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00378/48976/49383.pdf |
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| Registros recuperados: 33 | |
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