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| Registros recuperados: 50 | |
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| Feraud, Gilbert; Gastaud, Janine; Auzende, Jean-marie; Olivet, Jean-louis; Cornen, Guy. |
| Gorringe Bank is situated on the Europe-Africa plate boundary at the eastern end of the Azores-Gibraltar fracture zone. It has two summits. Gettysburg Bank to the southwest and Ormonde Bank to the northeast. We applied the 40Ar/39AR stepwise heating method to date six samples of the alkaline volcanic rocks. Two gabbros from the Ormonde Bank and a dolerite from the Gettysburg Bank. The results suggest that the alkaline volcanism lasted probably for less than 6 Ma(66-60 Ma). Although the nature of this volcanism precludes any subduction feature during its setting. the alkaline volcanism of Ormonde is probably linked to Upper Cretaceous/Eocene compressive tectonic events. The basement rocks of Gorringe Bank reveal disturbed 40Ar/39Ar age spectra. One... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1981 |
URL: http://archimer.ifremer.fr/doc/1981/publication-5365.pdf |
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| Bache, Francois; Popescu, Speranta-maria; Rabineau, Marina; Gorini, Christian; Suc, Jean-pierre; Clauzon, Georges; Olivet, Jean-louis; Rubino, Jean-loup; Melinte-dobrinescu, Mihaela Carmen; Estrada, Ferran; Londeix, Laurent; Armijo, Rolando; Meyer, Bertrand; Jolivet, Laurent; Jouannic, Gwenael; Leroux, Estelle; Aslanian, Daniel; Dos Reis, Antonio Tadeu; Mocochain, Ludovic; Dumurdzanov, Nikola; Zagorchev, Ivan; Lesic, Vesna; Tomic, Dragana; Cagatay, M. Namik; Brun, Jean_pierre; Sokoutis, Dimitrios; Csato, Istvan; Ucarkus, Gulsen; Cakir, Ziyadin. |
| The Messinian Salinity Crisis is well known to have resulted from a significant drop of the Mediterranean sea level. Considering both onshore and offshore observations, the subsequent reflooding is generally thought to have been very sudden. We present here offshore seismic evidence from the Gulf of Lions and re-visited onshore data from Italy and Turkey that lead to a new concept of a two-step reflooding of the Mediterranean Basin after the Messinian Salinity Crisis. The refilling was first moderate and relatively slow accompanied by transgressive ravinement, and later on very rapid, preserving the subaerial Messinian Erosional Surface. The amplitude of these two successive rises of sea level has been estimated at =500 similar to m for the first rise and... |
| Tipo: Text |
Palavras-chave: Paleo environmental changes; Miocene pliocene boundary; Section marche province; Earliest zanclean age; Desiccated deep basin; Di tetto formations; Northern apennines; Southern France; Decic basin; Depositional environments. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00076/18774/16490.pdf |
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| Baztan, Juan; Berne, Serge; Olivet, Jean-louis; Rabineau, Marina; Aslanian, Daniel; Gaudin, Mathieu; Rehault, Jean Pierre; Canals, M. |
| A detailed morphological analysis of the outer shelf and continental slope of the Western Gulf of Lion is presented, based on swath bathymetry data together with sub-bottom profiles and high resolution seismic reflection profiles. These data reveal two main erosive features, of very different dimensions: the axial incision and the canyon's major valley. The height of axial incisions' flanks with respect to the canyon deepest point (the thalweg) ranges from 40 to 150 m. It creates a small axial erosive path within the canyon's major valley, which is typically bounded by flanks of more than 700 m in height. We interpret the axial incision observed in the sea floor as the imprint of turbidity currents that eroded the floor of canyons during phases of... |
| Tipo: Text |
Palavras-chave: Submarine canyon; Axial incision; Gulf of Lion. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-353.pdf |
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| Le Lann, Alain; Auzende, Jean-marie; Olivet, Jean-louis. |
| We present in this paper raw data and preliminary results of CYAGOR dives (July-August 1977) on Gorringe bank (SW Portugal). A series of eight dives with submersible SP 3000 Cyana, from 2 600 to 40 m depth, enabled us to observe the outcrop of the bank flanks, a nearly complete cross-section of oceanic crust and upper mantle. The structure seems to be little affected by fracturing and is slightly rocked to the NE. Cross-sections made during the dives show characteristics similar to those of an ophiolitic complex. |
| Tipo: Text |
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| Ano: 1979 |
URL: https://archimer.ifremer.fr/doc/00418/52940/53880.pdf |
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| Klingelhoefer, Frauke; Labails, Cinthia; Cosquer, Emmanuel; Rouzo, Stephane; Geli, Louis; Aslanian, Daniel; Olivet, Jean-louis; Sahabi, M.; Nouze, Herve; Unternehr, P.. |
| A total 1500 km of seismic reflection and wide-angle profiles were acquired off the southern Moroccan margin during the DAKHLA cruise, a joint project of Ifremer, the Universities of Brest, El Jadida and Lisbon and Total. The shots along two profiles parallel to the margin and two profiles perpendicular to the margin were also recorded by ocean bottom seismometers (OBS). The profiles perpendicular to the margin were additionally extended on land using 14 stations on the northern profile and 11 stations on the southern profile. Modelling of the reflection and wide-angle seismic data reveals a 10 km deep sedimentary basin including two high velocity carbonate layers. Lateral crustal thinning is observed from a 27 km thick crystalline continental crust to a 7... |
| Tipo: Text |
Palavras-chave: Ocean continent transition; Keyword wide angle seismic; Southern Moroccan margin. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6410.pdf |
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| Olivet, Jean-louis; Auzende, Jean-marie; Mascle, Jean; Monti, S.; Pastouret, Léo; Pautot, Guy. |
| Recent data on the western Mediterranean basin (Joides cruise, Montadert et al., 1970, Auzende et al., 1971, Le Borgne et al., 1971) and its connection with the evolution of the Atlantic area (Le Pichon et al., 1970, Talwani et al., 1971, Le Pichon et al. in writing) lead us, like other authors (Dubourdieu, 1962, Stanley and Mutti, 1968, Ryan, 1969 amongst others) to admit the theory of an opening of the Algero-provencal basin during the Cenozoic era. A series of arguments drove us to formulate the hypothesis of an Oligocene age (in process). This work is in line with this perspective. [...] |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1971 |
URL: http://archimer.ifremer.fr/doc/1971/publication-4907.pdf |
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| Moulin, Maryline; Aslanian, Daniel; Olivet, Jean-louis; Contrucci, Isabelle; Matias, Luis; Geli, Louis; Klingelhoefer, Frauke; Nouze, Herve; Rehault, Jean Pierre; Unternehr, Patrick. |
| Deep penetration multichannel reflection and Ocean Bottom Seismometer wide-angle seismic data from the CongoAngola margin were collected in 2000 during the ZaïAngo cruise. These data help constrain the deep structure of the continental margin, the geometry of the pre-salt sediment layers and the geometry of the Aptian salt layer. Dating the deposition of the salt relative to the chronology of the margin formation is an issue of fundamental importance for reconstructing the evolution of the margin and for the understanding of the crustal thinning processes. The data show that the crust thins abruptly, from a 3040 km thickness to less than 10 km, over a lateral distance of less than 50 km. The transitional domain is a 180-km-wide basin. The pre-salt sediment... |
| Tipo: Text |
Palavras-chave: Deep seismic reflection and refraction; Sub salt imaging; Transitional domain; Crustal structure; Non volcanic passive continental margin. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/2005/publication-349.pdf |
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| Bache, Francois; Gorini, C; Olivet, Jean-louis; Rabineau, Marina; Aslanian, Daniel; Baztan, Juan; Moulin, Maryline. |
| The Messinian erosional surface that can be observed on the Mediterranean margins is a good marker of the relative lowering of the sea level which happened during the Messinian salinity crisis. The estimate of the volume of Miocene sediments on the Gulf of Lion platform gives a minimum eroded volume of 5 300 Km . The eroded layer reaches one kilometre in numerous places (Figures 2 and 3). This volume demonstrates the erosion of the continental shelf in the Gulf of Lion and does not include the eroded volumes in the Rhone valley, the surroundings of the Gulf of Lion and on the slope. Thus, this minimum eroded volume is logically transferred towards the basin. |
| Tipo: Text |
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| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/acte-4680.pdf |
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| Olivet, Jean-louis; Sichler, Bertrand; Thonon, Pierre; Le Pichon, Xavier; Martinais, Guy; Pautot, Guy. |
| The Gibbs fracture moves the central Rift of the Mid-Atlantic Ridge 370 km to the left at latitude 53O north. It is the only fracture located between Europe and America that can be compared to the large equatorial fractures mapped by B.C. Heezen and M. Tharp between Africa and America. Its morphology is a major element in the understanding of the structural framework of the northern Atlantic Ocean. The identification of its extension to the west was one of the proposed focuses for the first Noratlante expedition of the R.V. Jean-Charcot (conducted in August 1969 under the authority of the C.N.E.X.O.). J.T. Wilson (2) suggested, in his hypothesis of sea-bed spreading from the dorsal axis, that such fractures are "transforming faults" that are active only... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1970 |
URL: http://archimer.ifremer.fr/doc/1970/publication-4875.pdf |
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| Olivet, Jean-louis; Le Pichon, Xavier; Laubier, Lucien. |
| The cold waters from the Norwegian Sea are the main source of the underflow system in the northern Atlantic Ocean (10) (pl. 1, fig. 1b). The role of these currents in the formation of large sediment ripples has been demonstrated in some recent studies [(2), (3)]. As in the southern Atlantic Ocean, the observations suggested that their influence had been of importance since the Eocene era (6). From a sedimentological point of view, it appears that the Gibbs fracture (4) represents a very important feature in this system; this structure both forms a deep opening through the Mid-Atlantic Ridge and a dam across the abyssal plain to the northeast of Newfoundland. This dam, which is still active today, though partly flooded, must have been continuous from the... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1970 |
URL: http://archimer.ifremer.fr/doc/1970/publication-4882.pdf |
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| Auzende, Jean-marie; Olivet, Jean-louis; Bonnin, Jean. |
| Some seismic and magnetic profiles carried out south of the Big Bank of Newfoundland during the Noratlante cruise show a fracture zone which collapses the continental margin and continues to the south-east towards the Azores. This fracture zone proves evidence of the drift movement of Africa towards the east during the Jurassic or Trias opening of the Atlantic. From the south-east corner of the Big Bank, the fracture zone supports a sediment ridge formed by the underflows and which continues to the meridian 430 West. |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1970 |
URL: http://archimer.ifremer.fr/doc/1970/publication-4877.pdf |
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| Auzende, Jean-marie; Bonnin, Jean; Olivet, Jean-louis. |
| Based on the study of some seismic-reflection profiles, we demonstrate that the identified sedimentary units show a structural anomaly at the bottom of the North-African continental margin compared to the situation observed on the other margins of the western Mediterranean basin: all the deep Messinian and infra-Messinian deposits are subjected to a flexure when reaching the North-African margin; the created depression is filled by the plio-quaternary deposits. This observation, set back in the geodynamic context of the western Mediterranean, leads to the following interpretation: the North-African margin is a very active margin at a very early evolutional stage. The abnormal structure of the gravity field in the considered region confirms this... |
| Tipo: Text |
Palavras-chave: Histoire Ifremer. |
| Ano: 1975 |
URL: http://archimer.ifremer.fr/doc/1975/publication-5473.pdf |
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| Registros recuperados: 50 | |
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