Consulta: subjectFacets:"Margin"
Registros recuperados: 10
Data/hora: 04/06/2024 06:38:22

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: Institutional Archive of Ifreme (ArchiMer)
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

Analysis of slope failures in submarine canyon heads: An example from the Gulf of Lions
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Sultan, Nabil; Gaudin, Mathieu; Berne, Serge; Canals, Miquel; Urgeles, Roger; Lafuerza, Sara.
To improve understanding of evolution of submarine canyons, a three-dimensional slope-stability model is applied to Bourcart Canyon in the western Gulf of Lions in the Mediterranean Sea. The model builds on previous work by Chen and others, and it uses the upper bound theorem of plasticity to calculate the factor of safety of a kinematically admissible failing mass. Examples of three-dimensional failure surfaces documented in the literature were used to test the model formulation. Model application to Bourcart Canyon employed the results of a detailed stratigraphic analyses based on data acquired by swath bathymetry, sub-bottom profiling, high-resolution seismic reflection surveys, and piston coring. The sediment layers were also characterized using...
Tipo: Text
Palavras-chave: Cascadia accretionary complex; Upper bound theorem; Stability analysis; Continental slope; Limit equilibrium; Western gulf; Offshore; Margin; Initiation; Sediment.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2410.pdf

Searching for the seafloor signature of the 21 May 2003 Boumerdès earthquake offshore central Algeria
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Cattaneo, Antonio; Babonneau, Nathalie; Ratzov, G.; Dan-unterseh, G.; Yelles, K.; Bracene, R.; De Lepinay, B. Mercier; Boudiaf, A.; Deverchere, Jacques.
Shaking by moderate to large earthquakes in the Mediterranean Sea has proved in the past to potentially trigger catastrophic sediment collapse and flow. On 21 May 2003, a magnitude 6.8 earthquake located near BoumerdSs (central Algerian coast) triggered large turbidity currents responsible for 29 submarine cable breaks at the foot of the continental slope over similar to similar to 150 km from west to east. Seafloor bathymetry and backscatter imagery show the potential imprints of the 2003 event and of previous events. Large slope scarps resulting from active deformation may locally enhance sediment instabilities, although faults are not directly visible at the seafloor. Erosion is evident at the foot of the margin and along the paths of the numerous...
Tipo: Text
Palavras-chave: Western mediterranean sea; Cascadia subduction zone; Turbidity current; Zemmouri earthquake; Sedimentary processes; Submarine landslides; Northern algeria; Margin; Gps; Boundary.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00098/20959/18571.pdf

Active faulting and deep crustal structure of the Eastern Sicily Margin
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Dellong, David.
In the Ionian Sea (central Mediterranean) the slow convergence between Africa and Eurasia results in the formation of a narrow subduction zone. The nature of the crust of the subducting plate remains debated and could represent the last remnants of the Neo-Tethys ocean. The origin of the Ionian basin is also under discussion, especially concerning the rifting mechanisms as the Malta Escarpment could represent a remnant of this opening. This subduction retreats toward the south-east (motion occurring since the last 35 Ma) but is confined to the narrow Ionian basin. A major lateral slab tear fault is required to accommodate the slab rollback.This fault is thought to propagate along the eastern Sicily margin but its precise location remains controversial.This...
Tipo: Text
Palavras-chave: Méditerranée; Ionien; Calabre; Géodynamique; Marge; Faille de déchirure lithosphérique; Sismicité; Sismique; Grand-angle; Bathymétrie; Gravimétrie; Modélisation; Mediterranean; Ionian; Calabria; Geodynamic; Subduction; Margin; STEP fault; Wide-angle seismic; Seismicity; Bathymetry; Gravity; Modelling.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00499/61026/64430.pdf

Tectonic history along the South Gabon Basin: Anomalous early post-rift subsidence
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Dupre, Stephanie; Bertotti, Giovanni; Cloetingh, Sierd.
An integrated study of the South Gabon Margin (South Atlantic) based on reflection seismic and well data has been performed to quantify tectonic activity. A regional profile crossing the entire basin together with subsidence analysis, highlights important aspects of the post-rift history. The most striking event in the margin evolution appears to be the anomalous extra subsidence during the early post-rift period characterized by high sedimentation rates, equivalent to one third of the syn-rift subsidence. Although the presence of evaporite layers restricts knowledge of the underlying structures essentially composed of pre-rift and syn-rift sequences, the outcome of this post-rift tectonic study has strong implications for the rifting history. The early...
Tipo: Text
Palavras-chave: Post-rift subsidence; Margin; Gabon.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-6803.pdf

Origine et circulation des fluides dans les sédiments des marges. Contribution de l'hélium et du méthane dans la compréhension des processus. Étude de 2 zones actives
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Chaduteau, Carine.
Fluid migration is a very important process in marine sediments on margins. Studying fluids is fundamental to constrain the energy potential of margins. Methane is the predominant gas in marine sediments, deriving primarily from the degradation of organic matter. However methane could be also generated through the serpentinization of mantle rocks underlying the sedimentary cover in some specific geodynamical settings. One way to test this hypothesis is to use helium isotopes, which are known to be powerful tracers of the fluid-mantle interaction. To this purpose, a new method has been developed for the sampling and the quantitative extraction of dissolved helium from sediment pore-waters. During the Zairov2 and Vicking cruises, samples were collected in...
Tipo: Text
Palavras-chave: Mantle; Serpentinization; Advection; Mud volcano; Pockmark; Methane; Helium; Fluid; Margin; Manteau; Serpentinisation; Advection; Volcan de boue; Pockmark; Méthane; Hélium; Fluide; Marge.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/these-3724.pdf

Comment on "Zemmouri earthquake rupture zone (M-w 6.8, Algeria): Aftershocks sequence relocation and 3D velocity model" by A. Ayadi et al.
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Deverchere, Jacques; De Lepinay, Bernard Mercier; Cattaneo, Antonio; Strzerzynski, Pierre; Calais, Eric; Domzig, Anne; Bracene, Rabah.
Although often difficult to characterize, the relationship between a seismic rupture, its aftershock sequence, and cumulative subsurface or surface faulting or folding is an important challenge to modern seismology and seismotectonics. Among other benefits, it helps document fault length, slip, and magnitude relationships, reconstruct the evolution of the rupture process through historical and prehistorical times and identify the complexity of the deformation in its path toward the surface. This approach is a prerequisite to any seismic hazard assessment but is particularly difficult for faults whose surface trace projects offshore. A specific effort to identify and quantify the source parameters of large earthquakes in coastal areas is therefore needed,...
Tipo: Text
Palavras-chave: Boumerdès-Zemmouri earthquake; Deformation; Kinematics; Margin.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11440/7994.pdf

Cooperative Marketing of Animal Health Products
Provedor de dados: Research in Agricultural & Applied Economics (AgEcon Searh)
Autores: Vogelsang,   Donald L.
This report uses eight case studies to identify elements of successful cooperative programs for retailing over-the-counter animal health products (AHP). It provides practical information on AHP marketing strategies and methods for cooperative retailers, planners, and researchers. All participating cooperatives except one provided information for fiscal years ending during calendar year 1986. The exception was for 1987. Information. about five AHP suppliers and their marketing programs is included to enhance understanding of retailer programs.
Tipo: Report
Palavras-chave: Cooperative; Advertising; Animal health products; Centralized; Federated; Local; Margin; Marketing; Over-the-counter; Agribusiness; Livestock Production/Industries.
Ano: 1989
URL: http://purl.umn.edu/51282

Oligopsony Power: Evidence from the U.S. Beef Packing Industry
Provedor de dados: Research in Agricultural & Applied Economics (AgEcon Searh)
Autores: Cai,   Xiaowei; Stiegert,   Kyle W.; Koontz,   Stephen R.
Replaced with revised version of paper 08/24/09.
Tipo: Conference Paper or Presentation
Palavras-chave: Margin; Beef Packing; Fed Cattle Prices; Markov Regime Switching; Industrial Organization.
Ano: 2009
URL: http://purl.umn.edu/49364

Managing Price Risk in Volatile Grain Markets, Issues and Potential Solutions
Provedor de dados: Research in Agricultural & Applied Economics (AgEcon Searh)
Autores: McKenzie,   Andrew M.; Kunda,   Eugene L.
During 2008 extreme price volatility in grain markets led to country elevators incurring unprecedentedly large margin calls on their futures hedges. As a result elevators’ traditional liquidity sources and lines of credit were stretched to breaking point. This article explores the potential liquidity benefits of making available an Over-the-Counter Margin Credit Swap contract to grain hedgers. The swap would enable hedgers to draw upon sources of capital outside the farm credit system to provide liquidity needed to make margin calls. Simulation results clearly show that a Margin Credit Swap contract would provide significant liquidity benefits to hedgers during volatile periods.
Tipo: Journal Article
Palavras-chave: Elevator; Hedging; Margin; Swap; Agribusiness; Agricultural Finance; Crop Production/Industries; Risk and Uncertainty; G32; G13; Q14.
Ano: 2009
URL: http://purl.umn.edu/53081