Consulta: subjectFacets:"Fluid flow"
Registros recuperados: 9
Data/hora: 08/06/2024 15:20:23

Changes in seabed morphology, mud temperature and free gas venting at the Håkon Mosby mud volcano, offshore northern Norway, over the time period 2003-2006
Provedor de dados: 5
Autores: Foucher, Jean-paul; Dupre, Stephanie; Scalabrin, Carla; Feseker, Tomas; Harmegnies, Francois; Nouze, Herve.
The Håkon Mosby mud volcano is a 1.5-km-diameter geological structure located on the Southwest Barents Sea slope at a water depth of 1,270 m. High-definition seabed mapping of the mud volcano has been carried out in 2003 and 2006. A comparative analysis of the bathymetry and backscatter maps produced from the two surveys shows subtle morphological changes over the entire crater of the mud volcano, interpreted to be the consequence of mud eruption events. Mud temperature measurements point to a persistently warm mud at shallow depth in the crater. This is explained by upward fluid advection, rather than conductive cooling of mud flows. The small-scale spatial variability in the temperature distribution may be related to mud outflows or changes in the fluid...
Tipo: Text
Palavras-chave: Sw barents sea; Cold seep ecosystems; Fluid flow; Methane; Sediment; Onshore; Fluxes; Margin; Water.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00004/11527/10261.pdf

Physical and chemical factors influencing species distributions on hydrothermal sulfide edifices of the Juan de Fuca Ridge, northeast Pacific
Provedor de dados: 5
Autores: Sarrazin, Jozee; Juniper, Sk; Massoth, G; Legendre, P.
This study examines relationships between hydrothermal vent species and their surrounding physical and chemical environment on 2 high-temperature sulfide edifices of the Juan de Fuca Ridge (northeast Pacific). Video imagery and in situ temperature and chemical information were acquired during 2 remotely operated vehicle (ROV) dive programs in 1993 and 1995, for a total of 78 scans. Statistical analyses of environmental and faunal data reveal a heterogeneous distribution (cor respondence analyses) of hydrothermal species and demonstrate a significant influence of local physical and chemical conditions on species distributions (canonical correspondence analyses). Results confirm the importance of hydrogen sulfide to the distribution of vent species as well...
Tipo: Text
Palavras-chave: Hydrothermal vent ecology; Physical and chemical factors; In situ measurements; Habitat characterization; Species distribution; Sulfide edifice; Statistical analyses; Fluid flow; Substratum types; Mosaic habitat.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00280/39113/37666.pdf

Focused hydrocarbon-migration in shallow sediments of a pockmark cluster in the Niger Delta (Off Nigeria)
Provedor de dados: 5
Autores: De Prunele, Alexis; Ruffine, Livio; Riboulot, Vincent; Peters, Carl A.; Croguennec, Claire; Guyader, Vivien; Pape, Thomas; Bollinger, Claire; Bayon, Germain; Caprais, Jean-claude; Germain, Yoan; Donval, Jean-pierre; Marsset, Tania; Bohrmann, Gerhard; Geli, Louis; Rabiu, Abdulkarim; Lescanne, Marc; Cauquil, Eric; Sultan, Nabil.
The Niger Delta is one of the largest hydrocarbon basin offshore Africa and it is well known for the presence of active pockmarks on the seabed. During the Guineco-MeBo cruise in 2011, long cores were taken from a pockmark cluster in order to investigate the state of its current activity. Gas hydrates, oil and pore-water were sampled for geochemical studies.  The resulting dataset combined with seismic data reveal that shallow hydrocarbon migration in the upper sedimentary section was focused exclusively within the pockmarks. There is a clear tendency for gas migration within the hydrate-bearing pockmarks, and oil migration within the carbonate-rich one. This trend is interpreted as a consequence of hydrate dissolution followed by carbonate precipitation...
Tipo: Text
Palavras-chave: Anaerobic oxidation of methane; Cluster of pockmarks; Fluid flow; Gas hydrates; Pore-water profiles; Transient state.
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00365/47647/47676.pdf

Hydrate dissolution as a potential mechanism for pockmark formation in the Niger delta
Provedor de dados: 5
Autores: Sultan, Nabil; Marsset, Bruno; Ker, Stephan; Marsset, Tania; Voisset, Michel; Vernant, Antoine-mathieu; Bayon, Germain; Cauquil, Eric; Adamy, J.; Colliat, J. L.; Drapeau, D.
Based on acquired geophysical, geological and geotechnical data and modeling, we suggest hydrate dissolution to cause sediment collapse and pockmark formation in the Niger delta. Very high-resolution bathymetry data acquired from the Niger delta reveal the morphology of pockmarks with different shapes and sizes going from a small ring depression surrounding an irregular floor to more typical pockmarks with uniform depression. Geophysical data, in situ piezocone measurements, piezometer measurements and sediment cores demonstrate the presence of a common internal architecture of the studied pockmarks: inner sediments rich in gas hydrates surrounded by overpressured sediments. The temperature, pressure and salinity conditions of the studied area have allowed...
Tipo: Text
Palavras-chave: Methane gas hydrate; Sea floor; Marine sediments; Pore pressure; Porous media; Continental margin; Clathrate hydrate; Fluid flow; Stability; Slope.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00012/12300/9092.pdf

Gas hydrate distributions in sediments of pockmarks from the Nigerian Margin - Results and interpretation from shallow drilling
Provedor de dados: 5
Autores: Wei, Jiangong; Pape, Thomas; Sultan, Nabil; Colliat, Jean-louis; Himmler, Tobias; Ruffine, Livio; De Prunele, Alexis; Dennielou, Bernard; Garziglia, Sebastien; Marsset, Tania; Peters, Carl A.; Rabiu, Abdulkarim; Bohrmann, Gerhard.
A joint research expedition between the French IFREMER and the German MARUM was conducted in 2011 using the R/V Pourquoi pas? to study gas hydrate distributions in a pockmark field (1141 – 1199 meters below sea surface) at the continental margin of Nigeria. The sea floor drill rig MeBo of MARUM was used to recover sediments as deep as 56.74 meters below seafloor. The presence of gas hydrates in specific core sections was deduced from temperature anomalies recorded during continuous records of infrared thermal scanning and anomalies in pore water chloride concentrations. In situ sediment temperature measurements showed elevated geothermal gradients of up to 258 °C/km in the center of the so-called pockmark A which is up to 4.6 times higher than that in the...
Tipo: Text
Palavras-chave: Gas hydrate; Pockmark; Chloride profile; Infrared thermal imaging; Fluid flow; Nigerian continental margin; MeBo drill rig.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00213/32382/30846.pdf

Biodiversity of Cold Seep Ecosystems Along the European Margins
Provedor de dados: 5
Autores: Vanreusel, Ann; Andersen, Ann C.; Boetius, Antje; Connelly, Douglas; Cunha, Marina R.; Decker, Carole; Hilario, Ana; Kormas, Konstantinos Ar.; Maignien, Lois; Olu, Karine; Pachiadaki, Maria; Ritt, Benedicte; Rodrigues, Clara; Sarrazin, Jozee; Tyler, Paul; Van Gaever, Saskia; Vanneste, Heleen.
During the European Commission's Framework Six Programme, HERMES, we investigated three main areas along the European margin, each characterized by the presence of seep-related structures exhibiting different intensity of activity and biological diversity. These areas are: (1) the Nordic margin with the Hakon Mosby mud volcano and many pockmarks, (2) the Gulf of Cadiz, and (3) the eastern Mediterranean with its hundreds of mud volcanoes and brine pool structures. One of the main goals of the HERMES project was to unravel the biodiversity associated with these seep-associated ecosystems, and to understand their driving forces and functions, using an integrated approach. Several multidisciplinary research cruises to these three areas provided evidence of...
Tipo: Text
Palavras-chave: Mosby mud volcano; Gulf of mexico; Cadiz ne atlantic; Deep sea fan; Community structure; Microbial communities; Fluid flow; Mediterranean sea; Carbonate crusts; Norwegian sea.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6375.pdf

Evaluation des apports fluviatiles dans l''estuaire de la Seine
Provedor de dados: 5
Autores: Avoine, J.
Economic activities and urbanization along the Seine watershed, are the main factors of increased river discharge with natural deposits. A long term supervision of this river has allowed the assessment of the liquid flow rate, the solid load, and the metallic pollution.
Tipo: Text
Palavras-chave: Seasonal variations; Trace metals; Sediment transport; Fluid flow; Brackishwater pollution; Estuarine sedimentation; River discharge.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/acte-1274.pdf

Seafloor instabilities and sediment deformation processes: the need for integrated, multi-disciplinary investigations
Provedor de dados: 5
Autores: Vanneste, Maarten; Sultan, Nabil; Garziglia, Sebastien; Forsberg, Carl Fredrik; L'Heureux, Jean-sebastien.
In this paper, we present the current practice of investigations of seafloor instabilities and deformation processes, based on extensive research conducted over the last years, which sets the scene for future research activities in this field. The mapping of the continental margins and coastal areas with ever increasing resolution systematically reveals evidence of instabilities and deformation processes, both active and palaeo-features. In order to properly assess the hazards and risks related to these features, an integrated and multi-disciplinary approach is essential, but challenging. Such an approach consists of combining field data (geophysics, geology, sedimentology, geochemistry and geotechnical data) with numerical simulations constrained by...
Tipo: Text
Palavras-chave: Marine geotechnics; Slope stability; Sediment failures; Fluid flow; Shear strength; Marine geophysics; Monitoring; Excess pore pressure; Site investigations.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00173/28378/26692.pdf

Types of fluid-related features controlled by sedimentary cycles and fault network in deepwater Nigeria
Provedor de dados: 5
Autores: Marsset, Tania; Ruffine, Livio; Ker, Stephan; Cauquil, E.; Gay, Aurelien.
The seismic characteristics of focused fluid-related features such as pockmarks and carbonate build-ups on the Nigerian continental slope have been investigated using complementary seismic data sets (reprocessed 3D exploration data and 2D Very High Resolution hull-mounted and near-bottom seismic data) coupled with the results of previous studies (sedimentological, geotechnical and geochemical analyses). The results show different types of fluid-related features within the hemipelagic phase of long duration (∼1 Myr) Turbidite/Hemipelagic cycles. They are the product of the disturbance of the hosting sediments following two main distinct processes: (1) no or low sediment deposition caused by fluid escape associated with seafloor settlement (benthic fauna,...
Tipo: Text
Palavras-chave: Niger delta; Fluid flow; Pockmark; Gas hydrates; Methane-derived carbonate; Fault network; Sedimentary cycles.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00405/51650/52199.pdf