Consulta: creatorFacets:"Roest, Walter"
Registros recuperados: 20
Data/hora: 09/06/2024 13:47:07

Building of the Amsterdam-Saint Paul plateau: A 10 Myr history of a ridge-hot spot interaction and variations in the strength of the hot spot source
Provedor de dados: 5
Autores: Maia, Marcia; Pessanha, Ivo; Courreges, Esther; Patriat, Martin; Gente, Pascal; Hemond, Christophe; Janin, Myriam; Johnson, Kevin; Roest, Walter; Royer, Jean-yves; Vatteville, Judith.
The Amsterdam-Saint Paul plateau results from a 10 Myr interaction between the South East Indian Ridge and the Amsterdam-Saint Paul hot spot. During this period of time, the structure of the plateau changed as a consequence of changes in both the ridge-hot spot relative distance and in the strength of the hot spot source. The joint analysis of gravity-derived crust thickness and bathymetry reveals that the plateau started to form at similar to 10 Ma by an increase of the crustal production at the ridge axis, due to the nearby hot spot. This phase, which lasted 3-4 Myr, corresponds to a period of a strong hot spot source, maybe due to a high temperature or material flux, and decreasing ridge-hot spot distance. A second phase, between similar to 6 and...
Tipo: Text
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00047/15865/13284.pdf

Le programme d’EXTension RAisonnée du PLAteau Continental (EXTRAPLAC). Enjeux pour les trois collectivités ultramarines du Pacifique (Nouvelle-Calédonie, Wallis &amp; Futuna, Polynésie française).
Provedor de dados: 5
Autores: Loubrieu, Benoit; Roest, Walter; Patriat, Martin; Loubersac, Lionel.
This article replaces the French program of legal extension of the continental shelf named EXTRAPLAC, interesting in particular the 3 overseas collectivities of the Pacific (New Caledonia, Wallis and Futuna and French Polynesia)” It considers this program in the context of the Convention of the United Nations on the Maritime law. It clarifies the governance system of this program set up by the authorities of the State. A specific chapter clarifies the constraints to be respected to build up the necessary file in respect of the international Committee requirements so said UNO Commission of the Limits of the Continental shelf. The article considers then scenarios presented by 3 territories and state of progress of the three cases, both regarding the...
Tipo: Text
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00217/32820/31254.pdf

Neogene-Quaternary architecture and sedimentary processes on an isolated carbonate-fed deep-water basin (Fairway Basin, Southwest Pacific)
Provedor de dados: 5
Autores: Pattier, France; Etienne, S.; Collot, J; Patriat, Martin; Tournadour, Elsa; Roest, Walter; Rouillard, P.
The Fairway Basin is an intracratonic deep-water basin inherited from cretaceous rifting, perched between the Lord Howe Rise and the New Caledonia Basin in the Southwest Pacific. Its originality lies in its atypical present-day physiography and its carbonate-dominated sedimentary setting since the Miocene. Although very limited well controls are available, its overall structure, seismic stratigraphy and architecture are relatively well known. However, little is known on the detailed sedimentary processes controlling its recent infill. Its remote location from any major clastic sediment sources provides a great setting to study deep-water carbonate sedimentary processes. In this paper, we propose a detailed analysis of surface morphologies based on existing...
Tipo: Text
Palavras-chave: Deep-water carbonates; Submarine landslides; Turbidites; Polygonal faulting; Fluid escape; Fairway Basin.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00488/60001/63237.pdf

Pleistocene Mass Transport Deposits Off Barbados Accretionary Prism (Lesser Antilles)
Provedor de dados: 5
Autores: Pichot, Thibaud; Lafuerza, Sara; Patriat, Martin; Roest, Walter.
Two Pleistocene mass transport deposits (MTDs), with volumes of thousands of km(3), have been identified from multi-channel seismic data in the abyssal plain at the front of the Barbados accretionary prism. Estimated sediment volumes for these MTDs are likely underestimated due to limited seismic coverage. In this work, we suggest that these MTDs are comparable in size to large submarine landslides as reported in the literature. These MTDs lie on the vicinity of two major oceanic ridges, the Barracuda Ridge and the Tiburon Rise. It is also suggested in this work that the MTDs come from seismicity associated with the formation of the Barracuda Ridge or the Barbados accretionary prism; however, triggering mechanisms involved in their formation remain...
Tipo: Text
Palavras-chave: Lesser Antilles subduction zone; Barbados accretionary prism; Mass transport deposits; Subducted oceanic ridges.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00349/46066/46199.pdf

How supercontinents and superoceans affect seafloor roughness
Provedor de dados: 5
Autores: Whittaker, Joanne M.; Muller, R. Dietmar; Roest, Walter; Wessel, Paul; Smith, Walter H. F.
Seafloor roughness varies considerably across the world's ocean basins and is fundamental to controlling the circulation and mixing of heat in the ocean(1) and dissipating eddy kinetic energy(2). Models derived from analyses of active mid- ocean ridges suggest that ocean floor roughness depends on seafloor spreading rates(3), with rougher basement forming below a half- spreading rate threshold of 30 - 35 mm yr(-1) ( refs 4, 5), as well as on the local interaction of mid- ocean ridges with mantle plumes or coldspots(6). Here we present a global analysis of marine gravity- derived roughness, sediment thickness, seafloor isochrons and palaeo-spreading rates(7) of Cretaceous to Cenozoic ridge flanks. Our analysis reveals that, after eliminating effects related...
Tipo: Text
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6219.pdf

An alternative early opening scenario for the Central Atlantic Ocean
Provedor de dados: 5
Autores: Labails, Cinthia; Olivet, Jean-louis; Aslanian, Daniel; Roest, Walter.
The opening of the Central Atlantic Ocean basin that separated North America from northwest Africa is well documented and assumed to have started during the Late Jurassic. However, the early evolution and the initial breakup history of Pangaea are still debated: most of the existing models are based on one or multiple ridge jumps at the Middle Jurassic leaving the oldest crust on the American side, between the East Coast Magnetic Anomaly (ECMA) and the Blake Spur Magnetic Anomaly (BSMA). According to these hypotheses, the BSMA represents the limit of the initial basin and the footprint subsequent to the ridge jump. Consequently, the evolution of the northwest African margin is widely different from the northeast American margin. However, this setting is in...
Tipo: Text
Palavras-chave: Central Atlantic Ocean; Mesozoic reversals; Volcanism; Fracture zones; Spreading asymmetry; Plate reconstructions.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00014/12533/17926.pdf

A synthesis of the sedimentary evolution of the Demerara Plateau (Central Atlantic Ocean) from the late Albian to the Holocene
Provedor de dados: 5
Autores: Fanget, Anne-sophie; Loncke, Lies; Pattier, France; Marsset, Tania; Roest, Walter; Tallobre, Cédric; Durrieu De Madron, Xavier; Hernandez Molina, F. Javier.
The Demerara Plateau, off the French Guiana and Surinam margin, corresponds to a prominent sub-horizontal marginal plateau. The interpretation of a large set of seismic data acquired along the Demerara Plateau and integration with previous seismic stratigraphy and drill studies enables a better understanding of the sedimentary evolution of the outer Demerara marginal plateau. Since the end of the transform activity (late Albian), three sedimentary evolutionary stages have been identified. 1) The Pre-contourite Stage (late Albian to early Miocene) is strongly controlled by the structure of the margin that influences the distribution pattern of post-transform deposits through differential thermal subsidence between transform and divergent segments. 2) The...
Tipo: Text
Palavras-chave: Marginal plateau; Demerara Plateau; Contourite; Bottom currents; Mass transport deposits; Atlantic Ocean.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00599/71125/69439.pdf

Haiti-Drill: an amphibious drilling project workshop
Provedor de dados: 5
Autores: Aiken, Chastity; Wessels, Richard; Cormier, Marie-hélène; Klingelhoefer, Frauke; Battani, Anne; Rolandone, Frédérique; Roest, Walter; Boisson, Dominique; Guerrier, Kelly; Momplaisir, Roberte; Ellouz-zimmerman, Nadine.
The Haiti region – bounded by two strike-slip faults expressed both onshore and offshore – offers a unique opportunity for an amphibious drilling project. The east–west (EW)-striking, left lateral strike-slip Oriente–Septentrional fault zone and Enriquillo–Plantain Garden fault zone bounding Haiti have similar slip rates and also define the northern and southern boundaries of the Gonâve Microplate. However, it remains unclear how these fault systems terminate at the eastern boundary of that microplate. From a plate tectonic perspective, the Enriquillo–Plantain Garden fault zone can be expected to act as an inactive fracture zone bounding the Cayman spreading system, but, surprisingly, this fault has been quite active during the last 500 years. Overall,...
Tipo: Text
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00662/77402/79042.pdf

Lithospheric structuration onshore-offshore of the Sergipe-Alagoas passive margin, NE Brazil, based on wide-angle seismic data
Provedor de dados: 5
Autores: Pinheiro, Joao Marcelo; Schnurle, Philippe; Evain, Mikael; Afilhado, A.; Gallais, Flora; Klingelhoefer, Frauke; Loureiro, Afonso; Fuck, R.; Soares, J.; Cupertino, J. A.; Viana, A.; Rabineau, Marina; Baltzer, Agnes; Benabdellouahed, Massinissa; Dias, N.; Moulin, Maryline; Aslanian, Daniel; Morvan, Laetitia; Maze, Jean-pierre; Pierre, Delphine; Pitel-roudaut, Mathilde; Rio, I; Alves, D.; Barros Junior, P.; Biari, Youssef; Corela, C.; Crozon, Jacques; Duarte, J. L.; Ducatel, Cecile; Falcao, C.; Fernagu, Philippe; Le Piver, David; Mokeddem, Zohra; Pelleau, Pascal; Rigoti, C.; Roest, Walter; Roudaut, Mickael.
The structure and nature of the crust underlying the Camamu-Almada-Jequitinhonha-Sergipe-Alagoas basins System, in the NE Brazilian margin, were investigated based on the interpretation of 12 wide-angle seismic profiles acquired during the SALSA (Sergipe ALagoas Seismic Acquisition) experiment in 2014. In this work, we present two 220-km-long NW-SE combined wide-angle and reflection seismic profiles, SL 01 and SL 02, that have been acquired using 15 ocean-bottom-seismometers along each profile, offshore the southern part of the Sergipe Alagoas Basin (SAB), north of the Vaza-Barris Transfer zone. The SL 02 has a 150-km long inland continuation with 20 land-seismic-stations until the Sergipano Fold Belt (SFB). Wide-angle seismic forward modeling allows us to...
Tipo: Text
Palavras-chave: South Atlantic ocean; NE Brazil; Sergipe-Alagoas basin; Passive margins; Wide-angle refraction seismics; Crustal structure; Tectonic inheritance.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00461/57263/59315.pdf

Age, spreading rates, and spreading asymmetry of the world's ocean crust
Provedor de dados: 5
Autores: Muller, R; Sdrolias, M; Gaina, C; Roest, Walter.
We present four companion digital models of the age, age uncertainty, spreading rates, and spreading asymmetries of the world's ocean basins as geographic and Mercator grids with 2 arc min resolution. The grids include data from all the major ocean basins as well as detailed reconstructions of back-arc basins. The age, spreading rate, and asymmetry at each grid node are determined by linear interpolation between adjacent seafloor isochrons in the direction of spreading. Ages for ocean floor between the oldest identified magnetic anomalies and continental crust are interpolated by geological estimates of the ages of passive continental margin segments. The age uncertainties for grid cells coinciding with marine magnetic anomaly identifications, observed or...
Tipo: Text
Palavras-chave: Seafloor spreading; Geodynamic; Plate kinematic; Ocean floor; Digital isochrons.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3900.pdf

Structure of the Demerara passive-transform margin and associated sedimentary processes. Initial results from the IGUANES cruise
Provedor de dados: 5
Autores: Loncke, L.; Maillard, A.; Basile, C.; Roest, Walter; Bayon, Germain; Gaullier, V.; Pattier, France; Mercier De Lépinay, Marion; Grall, Celine; Droz, L.; Marsset, Tania; Giresse, P.; Caprais, Jean-claude; Cathalot, Cecile; Graindorge, D.; Heuret, A.; Lebrun, J. F.; Bermell, Sylvain; Marcaillou, B.; Sotin, C.; Hebert, B.; Patriat, Martin; Bassetti, M. A.; Tallobre, Cedric; Buscail, R.; Durrieu De Madron, X.; Bourrin, F.
he IGUANES cruise took place in May 2013 on the R/V L'Atalante along the Demerara passive transform margin off French Guiana and Surinam. Seismic, multibeam and chirp acquisitions were made. Piston cores were collected for pore geochemistry and sedimentology. A mooring was deployed on the sea-bottom for 10 months (temperature, salinity, turbidity and current measurements). This new dataset highlights the lateral variability of the 350 km-long Guiana–Surinam transform margin due to the presence of a releasing bend between two transform segments. The adjacent Demerara Plateau is affected by a 350 km-long giant slide complex. This complex initiated in Cretaceous times and was regularly reactivated until recent times. Since the Miocene, contourite processes...
Tipo: Text
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00428/53942/55285.pdf

New Caledonia obducted Peridotite Nappe: offshore extent and implications for obduction and post-obduction processes
Provedor de dados: 5
Autores: Patriat, Martin; Collot, Julien; Etienne, Samuel; Poli, Sara; Clerc, Camille; Mortimer, Nick; Pattier, France; Juan, Caroline; Roest, Walter.
One of the largest ophiolitic peridotite masses in the world covers a quarter of the island of Grande Terre, New Caledonia. The Peridotite Nappe was obducted during the Eocene, is weakly deformed and corresponds to the highest of a structurally simple pile of thrust nappes. We present new marine seismic data that allows us to track the offshore continuation of the Peridotite Nappe along‐strike for a distance of more than 500 km south of New Caledonia, and to image its pre‐, syn‐ and post‐obduction sedimentary records. Offshore, the Peridotite Nappe underlies a c. 150‐km wide and 2 km‐deep basin. Flat‐topped horsts of peridotite are clearly bounded by major normal faults; in contrast faults are obscure onland. To the east, the Peridotite Nappe roots along...
Tipo: Text
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00431/54242/55568.pdf

Transform continental margins – Part 2: A worldwide review
Provedor de dados: 5
Autores: Mercier De Lepinay, Marion; Loncke, Lies; Basile, Christophe; Roest, Walter; Patriat, Martin; Maillard, Agnes; De Clarens, Philippe.
We present a global inventory of transform continental margins, based on both a worldwide comparison of continent-ocean boundary identifications with oceanic fracture zones traces, and a compilation of published regional studies. This inventory increases the number of identified transform margins from 29 to 78. These margins represent 16% of continental margins in cumulative length and 31% of non-convergent margins. We include morphological data, published upper crustal sections, continent to ocean transition locations and published Moho shape data in the new database. This review confirms that continent to ocean transitions are sharper at transform margins than at divergent margins. It also emphasizes the structural diversity of transform margins....
Tipo: Text
Palavras-chave: Transform margin; Continental margin physiography; Marginal ridge; Marginal plateau.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00343/45372/44868.pdf

Geodynamics of the SW Pacific: a brief review and relations with New Caledonian geology
Provedor de dados: 5
Autores: Collot, Julien; Patriat, Martin; Sutherland, R.; Williams, S.; Cluzel, D.; Seton, M.; Pelletier, B.; Roest, Walter; Etienne, S.; Bordenave, A.; Maurizot, P.
The SW Pacific region consists of a succession of ridges and basins that were created by the fragmentation of Gondwana and the evolution of subduction zones since Mesozoic times. This complex geodynamic evolution shaped the geology of New Caledonia, which lies in the northern part of the Zealandia continent. Alternative tectonic models have been postulated. Most models agree that New Caledonia was situated on an active plate margin of eastern Gondwana during the Mesozoic. Extension affected the region from the Late Cretaceous to the Paleocene and models for this period vary in the location and nature of the plate boundary between the Pacific and Australian plates. Eocene regional tectonic contraction included the obduction of a mantle-derived Peridotite...
Tipo: Text
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00643/75543/76565.pdf

Seamounts, plateaus and governance issues in the southwest Indian Ocean, with emphasis on fisheries management and marine conservation, using the Walters Shoal as a case study for implementing a protection framework
Provedor de dados: 5
Autores: Marsac, Francis; Galletti, Florence; Ternon, Jean-francois; Romanov, Evgeny V.; Demarcq, Herve; Corbari, Laure; Bouchet, Philippe; Roest, Walter; Jorry, Stephan; Olu, Karine; Loncke, Lies; Roberts, Michael J.; Ménard, Frédéric.
There is a growing interest in the management of seamounts of the South Western Indian Ocean (SWIO) both in waters under national jurisdictions and in the Areas Beyond National Jurisdiction (ABNJ). On the one hand, new scientific knowledge has been gathered through various oceanographic cruises during the past decade and, on the other hand, new agreements are under consideration globally to promote conservation and sustainable use of the biodiversity in the ABNJ, where the deep sea ecosystems associated to seamounts are a growing matter of concern. SWIO seamounts have attracted interests from fishing operators since the 1960s, while mining exploration contracts have been recently granted. Seamounts are known to shelter rich, fragile and poorly resilient...
Tipo: Text
Palavras-chave: International Law of the Sea; Vulnerable Marine Ecosystems; Deep-sea fisheries; Deep-sea mining; Benthic biodiversity; Saya de Malha Bank; South Indian Ocean Fisheries Agreement; Areas Beyond National Jurisdiction; Amended Nairobi Convention; Marine protected areas.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00598/71049/69362.pdf

Slope instabilities from echo-character mapping along the French Guiana transform margin and Demerara abyssal plain
Provedor de dados: 5
Autores: 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

Oligocene-Miocene spreading history of the northern South Fiji Basin and implications for the evolution of the New Zealand plate boundary
Provedor de dados: 5
Autores: Herzer, R. H.; Barker, D. H. N.; Roest, Walter; Mortimer, N.
A tectonic model of the evolution of the northern half of the South Fiji Basin, including the Minerva Triple Junction and Cook Fracture Zone, is developed from regional gravity, multibeam bathymetry, and a new interpretation of magnetic anomalies pinned to radiometric dates of oceanic crust in the basin. The geometry and age of a portion of the Minerva Triple Junction and the Cook-Minerva spreading center (the connection from the triple junction to the Cook Fracture Zone, which accommodated coeval opening of the Norfolk Basin), are resolved with multibeam bathymetry and magnetics. The South Fiji Basin opened from about 34 to 15 Ma in an anticlockwise sweep about an Euler pole located at the northern end of the present Lau Ridge. This rotation and a rigidly...
Tipo: Text
Palavras-chave: South Fiji Basin; Back-arc basin evolution; Multibeam bathymetry; Magnetic anomalies; Gravity model; New Zealand plate boundary.
Ano: 2011
URL: http://archimer.ifremer.fr/doc/00030/14112/11362.pdf

Origin of an enigmatic regional Mio-Pliocene unconformity on the Demerara plateau
Provedor de dados: 5
Autores: Pattier, France; Loncke, L.; Imbert, Patrice; Gaullier, V.; Basile, C.; Maillard, Alexandre; Roest, Walter; Patriat, Martin; Vendeville, B. C.; Marsset, Tania; Bayon, Germain; Cathalot, Cecile; Caprais, Jean-claude; Bermell, Sylvain; Sotin, Christine; Hebert, Bertil; Mercier De Lepinay, Marion; Lebrun, J. F.; Marcaillou, B.; Heuret, A.; Droz, Laurence; Graindorge, David; Poetisi, E.; Berrenstein, H.
The Demerara plateau, located offshore French Guiana and Suriname, is part of a passive transform continental margin particularly prone to develop slope instabilities, probably in relation to the presence of a free distal border along its steep continental slope. Slope failure occurred at different periods (Cretaceous to Neogene) and shows an overall retrogressive evolution through time. Upslope these failure headscarp, an enigmatic regional MioPliocene unconformity has been discovered through the interpretation of new academic and industrial datasets. The aim of this work is to describe and understand the origin of this surface. Our analysis shows that this unconformity is made of a series of valleys that cross-cut sedimentary strata. Each one of these...
Tipo: Text
Palavras-chave: Unconformity; Hydrate pockmark; Slide; Contourite; Valley; Canyon; Demerara plateau.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00271/38193/36735.pdf

Mass-transport deposits and fluid venting in a transform margin setting, the eastern Demerara Plateau (French Guiana)
Provedor de dados: 5
Autores: Pattier, France; Loncke, L.; Gaullier, V.; Basile, C.; Maillard, Alexandre; Imbert, Patrice; Roest, Walter; Vendeville, B. C.; Patriat, Martin; Loubrieu, Benoit.
The eastern Demerara Plateau offshore French Guiana was surveyed in 2003 during the GUYAPLAC cruise (multibeam bathymetry and acoustic imagery, 6-channel seismic reflection and 3.5 kHz echo-sounding). The data show the "post-transform" Cenozoic that the series located on the outer part of the plateau (below c. 2000 m) contain at least twelve stacked mass transport deposits (MTDs) that have recorded a history of large-scale slope failure, as well as two main normal fault sets that provide possible pathways for upward fluid migration through the series, reaching at high as the uppermost MTDs. Seabed data show that the area above the failures is characterized by circular-to-elongate (slope-parallel) depressions interpreted as fluid seeps (pockmarks), some of...
Tipo: Text
Palavras-chave: Fluid ascent; Pockmarks; MTDs; Transform margin; Demerara Plateau.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00157/26850/25316.pdf

Transform Marginal Plateaus
Provedor de dados: 5
Autores: Loncke, L.; Roest, Walter; Klingelhoefer, Frauke; Basile, C.; Graindorge, David; Heuret, A.; Marcaillou, B.; Museur, Thomas; Fanget, Anne-sophie; Mercier De Lépinay, M.
Numerous submarine plateaus form highstanding bathymetric highs at continent to ocean transitions. Due to their proximity to continents, they have been frequently labelled “marginal plateaus”, although this term has not been clearly defined or associated with a specific geology or geodynamic process. Until now, these elevations have been interpreted as submerged thinned continental fragments detached from continents, basaltic buildups formed by hotspots, volcanic margins or oceanic plateaus. Many of these plateaus formed at transform margins connecting oceanic basins of contrasted ages. We propose for the first time to define and review a class of marginal plateaus related to a specific tectonic setting: “Transform Marginal Plateaus” (TMPs). Based on a...
Tipo: Text
Palavras-chave: Transform marginal plateau; Transform margin; Volcanic margin; Large Igneous Province; Continental breakup; Paleoceanography; Land bridge; Gateway.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00512/62407/66663.pdf