Éditeur(s) : Elsevier Science Bv
Résumé : 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 erosional rates identified in the Cilaos cirque during these intervals of both low effusive volcanic activity and enhanced rainfall level are probably the main driver of sediment supply to the deep‐sea depositional system. These new findings also highlight the important capacity of volcaniclastic turbidite systems to record rapid paleoenvironmental changes.
Sedimentary Geology (0037-0738) (Elsevier Science Bv), 2012-12 , Vol. 281 , P. 180-193

Droits : 2012 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/00105/21659/19383.pdf
DOI:10.1016/j.sedgeo.2012.09.010
http://archimer.ifremer.fr/doc/00105/21659/

Éditeur(s) : HAL CCSD
Résumé : International audience
Le but de cette étude était d'une part de déterminer si le recours à une stratégie d'envoi de « Short Message System » (SMS) pouvait augmenter l'Activité Physique Aérobie (APA) chez vingt-deux élèves de seconde afin qu'ils atteignent les recommandations de l'Organisation Mondiale de la Santé qui est de 60 minutes par jour d'activité ; d'autre part si cette stratégie avait une influence positive sur les performances dans une activité de course de durée en Education Physique et Sportive (EPS). Les résultats de cette étude mettent en évidence que recevoir un SMS le matin (6 fois par semaine pendant 3 semaines), invitant à réaliser une APA, augmente de façon significative la durée moyenne hebdomadaire d'APA (de loisir). De plus, une amélioration des temps de réalisation des 3 x 400 mètres (réalisés en début, milieu et fin d'un cycle de course de durée en EPS) est observée tout en étant supérieure lorsque les élèves reçoivent le SMS du matin que quand ils n'en ont pas reçu. L'utilisation des SMS est donc une stratégie efficace permettant de rendre les élèves plus actifs. Cette technique pourrait pleinement trouver sa place au sein d'un lycée dans le cadre d'un projet faisant un lien entre l'EPS, l'éducation à la santé et les Techniques de l'Information et de la Communication pour l'Enseignement. Mots clés : activité physique aérobie, éducation physique sportive, message électronique
Le Journal de la recherche sur l'intervention en éducation physique et sport (eJRIEPS)

Droits : info:eu-repo/semantics/OpenAccess
hal-01677451
https://hal.archives-ouvertes.fr/hal-01677451
https://hal.archives-ouvertes.fr/hal-01677451/document
https://hal.archives-ouvertes.fr/hal-01677451/file/Robin%2C%20laurent%2C%20ruart%2C%202018%20Influence%20des%20messages%20%C3%A9lectroniques%20sur%20l%E2%80%99activit%C3%A9%20physique%20a%C3%A9robie%20personnelle%20et%20les%20performances%20en%20%C3%A9ducation%20physique%20et%20sportive.pdf

Éditeur(s) : Elsevier Science Bv
Résumé : The Var turbiditic system located in the Ligurian Sea (SE France) is an intermediate mud/sand-rich system. The particularity of the Var deep-sea fan is its single channel with abrupt bends and its asymmetric and hyper-developed levee on the right hand side: the Var Sedimentary Ridge. Long-term sediment accumulation on the Var Sedimentary Ridge makes this an ideal target for studying the link between onshore climate change and deep-sea turbidite stratigraphy. This paper focuses on the establishment of the first detailed stratigraphy of the levee, which is used to analyze the timing of overbank deposition throughout the last deglaciation. Main results indicate that high variability in turbidite frequencies and deposition rates along the Var Sedimentary Ridge are determined by two main parameters: 1) the progressive decrease of the levee height controlling the ability of turbidity currents to spill out from the channel onto the levee, and 2) climatic variations affecting the drainage basin, in particular changes in glacial condition since late Last Glacial Maximum to early Holocene. Compared to other deep-water areas, this study confirms the ability of turbiditic systems to record past climatic events on millennial timescales, and underlines the influence of European deglaciation on the observed decrease in turbidite activity in the Var canyon. The presence of a very narrow continental shelf and a single, large channel-levee system makes the Var Sedimentary Ridge a unique example of climate-controlled turbiditic accumulations. (C) 2010 Elsevier B.V. All rights reserved.
Marine Geology (0025-3227) (Elsevier Science Bv), 2011-01 , Vol. 279 , N. 1-4 , P. 148-161

Droits : 2010 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/00030/14104/11370.pdf
DOI:10.1016/j.margeo.2010.10.021
http://archimer.ifremer.fr/doc/00030/14104/

Éditeur(s) : Elsevier Science Bv
Résumé : Volcaniclastic successions are well-described in volcanic arc setting but rare in hotspot environments. The present work proposes a facies model of volcaniclastic sedimentation related to basaltic hotspot volcanoes as exemplified by the Piton de la Fournaise volcano (La Réunion Island). The facies model is based on a multi-scale approach combining high-resolution multibeam and backscatter data, deep-water photographs, side scan imagery and Kullenberg piston cores. Data show that a wide range of gravity flows and erosional features develop in the active volcaniclastic sedimentary system. Coastal and submarine instabilities are the main processes shaping the volcano's submarine morphology. Meanwhile, the evolution and dynamics of the sedimentary system are strongly linked with the morpho-structural evolution of the subaerial part of the volcano. The proposed model is characterized by a cyclic succession of stages: (1) a growing stage during which sedimentary activity is mainly restricted to proximal and mid-slope areas; (2) a collapse stage that entirely reshapes the morphology of the submarine slopes; and (3) an erosional stage related to a slow down of volcanic activity, enabling the development of large deep-sea fans.
Marine Geology (0025-3227) (Elsevier Science Bv), 2013-03 , Vol. 337 , P. 35-52

Droits : 2013 Published by Elsevier B.V. All rights reserved
http://archimer.ifremer.fr/doc/00137/24798/22939.pdf
DOI:10.1016/j.margeo.2013.01.004
http://archimer.ifremer.fr/doc/00137/24798/