|
|
|
|
|
| Mazuel, Aude; Sisavath, Emmanuelle; Babonneau, Nathalie; Jorry, Stephan; Bachelery, Patrick; Delacourt, Christophe. |
| Recent marine geophysical surveys reveal the existence of well-developed volcaniclastic deep-sea fans around La Réunion Island, Indian Ocean. The Mafate turbidite complex, located in the northwestern part of the island, is a large sedimentary system formed by two coalescent-like volcaniclastic deep-sea fans: the Mafate fan and the Saint-Denis fan. They are both connected to terrestrial rivers supplying sediment produced by erosion on the island, particularly during austral summer cyclonic floods. Through the integration of marine geophysical data (including bathymetry, backscatter multibeam sounder images, TOBI side-scan sonar images and seismic reflection profiles) and piston cores, a submarine morpho-sedimentary map of the surface architecture of the... |
| Tipo: Text |
Palavras-chave: Deep-sea fan; Turbidite; Volcaniclastic; Land-to-sea transfer; La Reunion Island; Late Quaternary. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00312/42273/41597.pdf |
| |
|
|
| Bachelery, Patrick; Babonneau, Nathalie; Jorry, Stephan; Mazuel, Aude. |
| The discovery in 2006, during the oceanographic survey FOREVER, of large volcaniclastic sedimentary systems off La Réunion Island (western Indian ocean) revealed a new image of the evolution of oceanic shield volcanoes and their dismantling. Marine data obtained from 2006 to 2011 during the oceanographic surveys ERODER 1 to ERODER 4 included bathymetry, acoustic imagery, echosounding profiles, dredging and coring. Six major turbidite systems were mapped and described on the submarine flanks of La Reunion volcanic edifice and the surrounding oceanic plate. The interpretation of sediment cores enable us to characterise the processes of gravity-driven sediment transfer from land to deep sea and also to revisit the history of the volcanoes of La Réunion... |
| Tipo: Text |
|
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00200/31118/29529.pdf |
| |
|
|
| Babonneau, Nathalie; Delacourt, Christophe; Cancouet, R.; Sisavath, Emmanuelle; Bachelery, Patrick; Mazuel, Aude; Jorry, Stephan; Deschamps, Anne; Ammann, Jerome; Villeneuve, N.. |
| Submarine canyon heads are key areas for understanding the triggering factors of gravity currents responsible for the transfer of detrital sediment to the deep basins. This contribution offers a detailed picture of canyon heads off La Réunion Island, with high-resolution multibeam bathymetry in the water depth range of 4–220 m. The present feeding of the Cilaos turbidite system, one of the largest modern volcaniclastic systems in the world, is deduced from morphological and sedimentological interpretations of newly acquired data. The study highlights small-scale sedimentary features indicating hydrodynamic and sedimentary processes. A direct connexion between the Saint-Etienne river mouth and submarine canyons is evidenced by the complete incision of the... |
| Tipo: Text |
Palavras-chave: Submarine canyon; Canyon head; Turbidity current; Hyperpycnal flow; Coastal instability. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26697/24790.pdf |
| |
|
|
| Courgeon, Simon; Bachelery, Patrick; Jouet, Gwenael; Jorry, Stephan; Bou, Esther; Boudagher-fadel, Marcelle K.; Revillon, Sidonie; Camoin, Gilbert; Poli, Emmanuelle. |
| The offshore branch of the East African Rift System (EARS) has developed during late Cenozoic time along the eastern Africa continental margin. While Neogene–Pleistocene extensional tectonic deformation has been evidenced along the northern segment of the Davie Ridge, the spatial extent of deformation further south remains poorly documented. Based on recent and various oceanographic data sets (bathymetric surveys, dredge samples and seismic profiles), our study highlights active normal faulting, modern east–west extensional tectonic deformation and Late Cenozoic alkaline volcanism at the Sakalaves Seamounts (18°S, Davie Ridge) that seem tightly linked to the offshore EARS development. In parallel, rift‐related tectonic subsidence appears responsible for... |
| Tipo: Text |
|
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00452/56344/57934.pdf |
| |
|
|
| Sisavath, Emmanuelle; Mazuel, Aude; Jorry, Stephan; Babonneau, Nathalie; Bachelery, Patrick; De Voogd, Beatrice; Salpin, Marie; Emmanuel, Laurent; Beaufort, Luc; Toucanne, Samuel. |
| The present study focused on turbidite sedimentation in the Cilaos turbidite system, a volcaniclastic deep-sea fan recently recognized offshore La Réunion Island. A set of piston cores was collected in order to establish the stratigraphy of this fan and to examine the processes controlling the turbidite sedimentation off the Cilaos cirque (Piton des Neiges volcanic massif) over the last climatic cycle. Two main phases of turbidite activity were identified, during the ca 140–127 ka and 30–0 ka periods, coinciding with the two last glacial–interglacial transitions (i.e., Terminations II and I). In addition to changes in climate and eustatic sea-level, these periods coincide with a low effusive volcanic activity of the Piton des Neiges volcano. The high... |
| Tipo: Text |
Palavras-chave: Turbidites; La Reunion Island; Indian Ocean; Late Quaternary; Volcaniclastic system. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00105/21659/19383.pdf |
| |
|
|
| Sisavath, Emmanuelle; Babonneau, Nathalie; Saint-ange, Francky; Bachelery, Patrick; Jorry, Stephan; Deplus, Christine; De Voogd, Beatrice; Savoye, Bruno. |
| Recent oceanographic surveys revealed the existence of five volcaniclastic deep-sea fans off La Reunion Island. The Cilaos fan is a large volcaniclastic submarine fan, connected to rivers that episodically experience torrential floods through a narrow and steep shelf-slope system. New piston cores presented in this study together with echosounder profiles give new insight into the evolution, of this extensive and sand-rich turbidite system. The Cilaos fan extends over 15,000 km(2) on an abyssal plain and is compartmentalized by topographic highs. Located southwest of the island, the sedimentary system consists of a canyon area and a deep sea fan divided into a proximal and a distal fan. The proximal fan is characterized by its wide extent and... |
| Tipo: Text |
Palavras-chave: Turbidite; Deep-sea fan; Volcaniclastic; La Reunion Island. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00056/16704/14203.pdf |
| |
|
|
| Kong, Eleonore; Zaragosi, Sebastien; Schneider, Jean-luc; Garlan, Thierry; Bachelery, Patrick; Sabine, Marjolaine; San Pedro, Laurine. |
| In the Ionian Sea, the subduction of the Nubia plate underneath the Eurasia plate leads to an important sediment remobilization on the Calabrian Arc and the Mediterranean Ridge. These events are often associated with earthquakes and tsunamis. In this study, we analyze gravity-driven deposits in order to establish their recurrence time on the Calabrian Arc and the western Mediterranean Ridge. Four gravity cores collected on ridges and slope basins of accretionary prisms record turbidites, megaturbidites, slumping and micro-faults over the last 330,000 years. These turbidites were dated by correlation with a hemipelagic core with a multi-proxy approach: radiometric dating, 18O, b* colour curve, sapropels and tephrochronology. The origin of the gravity-driven... |
| Tipo: Text |
Palavras-chave: Ionian Sea; Accretionary wedges; Palaeoearthquakes; Etna volcanism; Natural hazard; Turbidites. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00638/75012/75691.pdf |
| |
|
| |
|
|
|
