|
|
|
|
|
| Mascle, J; Guiraud, M; Benkhelil, J; Basile, C; Bouillin, Jp; Mascle, G; Cousin, M; Durand, M; Dejax, J; Moullade, M. |
| During the Equanaute survey (June 1992), fourteen submersible dives were performed between 4950 and 2250 m water depths across the southern slope of the Cote d'Ivoire-Ghana Marginal Ridge (CIGMR), in the eastern Equatorial Atlantic. The CIGMR, a high-standing topographic marginal ridge along the Cote d'Ivoire-Ghana transform margin, is believed to result from a complex structural evolution due to the specific wrench-related rifting between Western Equatorial Africa and Northeastern Brazil, in Early Cretaceous times. In this paper we report and discuss geological observations made during dives, and sample analyses to resolve the lithology, paleoenvironmental conditions, age and origin of the CIGMR. The data help in better characterizing the different... |
| Tipo: Text |
Palavras-chave: Marge transformante; Géologie; Côte d’lvoire-Ghana; Atlantique Equatorial; Transform margin; Geology; Côte d’Ivoire-Ghana; Equatorial Atlantic. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00326/43694/43118.pdf |
| |
|
|
| Funck, T; Jackson, H; Louden, K; Klingelhoefer, Frauke. |
| [ 1] The Davis Strait transform margin was studied using a 630-km-long wide-angle reflection/ refraction seismic transect extending from SE Baffin Island to Greenland. Dense airgun shots were recorded by 28 ocean bottom seismometers deployed along the line. A P wave velocity model was developed from forward and inverse modeling of the wide-angle data and incorporation of coincident deep multichannel reflection seismic data. Off Baffin Island in the Saglek Basin, 7 to 11-km-thick two-layered continental crust (5.8 - 6.6 km/s) is observed. Off Greenland, continental crust is divided into three layers (5.4 - 6.8 km/s) with a maximum thickness of 20 km. Farther offshore Greenland the crust thins to 7 - 12 km and the lower crust disappears. Between the... |
| Tipo: Text |
Palavras-chave: Magmatic underplating; Refraction seismics; Transform margin. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-4393.pdf |
| |
|
|
| 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 |
| |
|
|
| 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 |
| |
|
|
| 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 |
| |
|
|
| 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 |
| |
|
|
|
