L’interculturalisme en revue : L’expérience de vice Versa

L’auteure de cet article s’intéresse à la notion de revue « interculturelle » à partir de l’exemple de vice Versa, un magazine transculturel publié entre les années 1983 et 1996. Comment ce type de revue, parfois créé par des groupes de migrants, s’inscrit-il dans les débats culturels et politiques d’une société ? C’est ce qui est abordé dans le contexte du Québec des années 1980 et 1990.The author uses the example of vice Versa, a transcultural magazine published between 1983 and 1996, to focus on the idea of the «intercultural» magazine. How does this kind of periodical, which is sometimes created by groups of migrants, fit into society’s cultural and political debates? This issue is analyzed in the context of 1980s and 1990s Québec

Dynamics of a laminar plume in a cavity: The influence of boundaries on the steady state stem structure

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96724/1/ggge20016.pd

« Ces belles voix à la dérive » : Jules Supervielle et le désir de théâtre

Florence Davaille étudie ici certains aspects de la genèse d’une pièce de théâtre de Jules Supervielle, Bolivar, jouée en 1936 à la Comédie-Française et reprise sous la forme d’un opéra en 1950. L’objectif est de montrer ce qui est au cœur des ré-écritures successives : incarner des voix dans des personnages, geste de création fondateur dans l’ontologie développée par Supervielle dès l’écriture de sa poésie. Au-delà du passage d’un genre à un autre, le choix d’écrire du théâtre chez Supervielle se révèle être l’étape ultime d’une « poétique de l’incarnation », ce qui rend cet aspect de son œuvre important, même s’il s’agit d’un théâtre très peu connu aujourd’hui.Florence Davaille studies some features of the genesis of Bolivar : one of pieces by Jules Supervielle, played in Comédie-Française in 1936 and reproduced as an opera in 1950. The paper aims to expose the core of the following play re-writings : personification of the characters’ voice – founding gesture of creation in the ontology developed by Supervielle starting from his poetical writings. Beyond passing from one literary genre to another, Supervielle’s choice of drama writing reveals to be an ultimate stage of the "poetics of incarnation" which makes this aspect of his works important, even if it is about a theatre which is quite unknown today

The evolution of mantle plumes in East Africa

Global tomography models show a large low‐velocity anomaly extending from the core‐mantle boundary (CMB) beneath South Africa to the upper mantle in East Africa. Although it is believed that this anomaly is linked to mantle upwellings that control key surface features of the African continent, its origin and evolution are still debated. Here we assemble geochemical and seismological constraints along with information from new seismic analyses and geodynamic laboratory experiments to propose that presently there are at least two different plume heads beneath Afar and Kenya that originated at the CMB. A third plume between Kenya and Afar may have caused the Ethiopia‐Yemen traps 30 Ma, now merging with the Afar plume. We infer that the Afar plume is presently detached from the CMB probably because of an interaction with the subducted Tethyan slab and that it is likely a dying plume. This may imply that rifts along the Main Ethiopian Rift would fail by the loss of thermal sources, which consequently hampers continental breakup

Wavelet-based directional analysis of the gravity field: evidence for large-scale undulations

International audienceIn the eighties, the analysis of satellite altimetry data leads to the major discovery of gravity lineations in the oceans, with wavelengths between 200 and 1400 km. While the existence of the 200 km scale undulations is widely accepted, undulations at scales larger than 400 km are still a matter of debate. In this paper, we revisit the topic of the large-scale geoid undulations over the oceans in the light of the satellite gravity data provided by the GRACE mission, considerably more precise than the altimetry data at wavelengths larger than 400 km. First, we develop a dedicated method of directional Poisson wavelet analysis on the sphere with significance testing, in order to detect and characterize directional structures in geophys-ical data on the sphere at different spatial scales. This method is particularly well suited for potential field analysis. We validate it on a series of synthetic tests, and then apply it to analyze recent gravity models, as well as a bathymetry data set independent from gravity. Our analysis confirms the existence of gravity undulations at large scale in the oceans, with characteristic scales between 600 and 2000 km. Their direction correlates well with present-day plate motion over the Pacific ocean, where they are particularly clear, and associated with a conjugate direction at 1500 km scale. A major finding is that the 2000 km scale geoid undulations dominate and had never been so clearly observed previously. This is due to the great precision of GRACE data at those wavelengths. Given the large scale of these undulations, they are most likely related to mantle processes. Taking into account observations and models from other geophysical information, as seismological tomography, convection and geochemical models and electrical conductivity in the mantle, we conceive that all these inputs indicate a directional fabric of the mantle flows at depth, reflecting how the history of subduction influences the organization of lower mantle upwellings

Small-scale convection in a plume-fed low-viscosity layer beneath a moving plate

Two-dimensional simulations using a thermomechanical model based on a finite-difference method on a staggered grid and a marker in cell method are performed to study the plume-lithosphere interaction beneath moving plates. The plate and the convective mantle are modelled as a homogeneous peridotite with a Newtonian temperature- and pressure-dependent viscosity. A constant velocity, ranging from 5 to 12.5 cm yr−1, is imposed at the top of the plate. Plumes are generated by imposing a thermal anomaly of 150 to 350 K on a 50 km wide domain at the base of the model (700 km depth); the plate atop this thermal anomaly is 40 Myr old. We analyse (1) the kinematics of the plume as it impacts the moving plate, (2) the dynamics of time-dependent small-scale convection (SSC) instabilities developing in the low-viscosity layer formed by spreading of hot plume material at the base of the lithosphere and (3) the resulting thermal rejuvenation of the lithosphere. The spreading of the plume material at the base of the lithosphere, characterized by the ratio between the maximum down- and upstream horizontal (dimensionless) velocities in the plume-fed sublithospheric layer, Peup/Pedown depends on the ratio between the maximum plume upwelling velocity and the plate velocity, Peplume/Peplate. For fast plate velocities and sluggish plumes (low Peplume/Peplate), plate motion drags most plume material and downstream flow is dominant. As Peplume/Peplate increases, an increasing part of the plume material flows upstream. SSC systematically develops in the plume-fed sublithospheric layer, downstream from the plume. Onset time of SSC decreases with the Rayleigh number. For vigorous plumes, it does not depend on plate velocity. For more sluggish plumes, however, variations in the plume spreading behaviour at the base of the lithosphere result in a decrease in the onset time of SSCs with increasing plate velocity. In any case, SSC results in uplift of the isotherm 1573 K by up to 20 km relative to its initial equilibrium depth at the impact poin

A noninvasive method for measuring the velocity of diffuse hydrothermal flow by tracking moving refractive index anomalies

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95358/1/ggge1802.pd

Starting laminar plumes: Comparison of laboratory and numerical modeling

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94953/1/ggge1631.pd

Mythes et réalités de l’écriture

Depuis quelques années, l’étude des interactions entre les langues et des divers phénomènes linguistiques repérables dans le champ de l’écriture multilingue constitue un axe d’investigation récurrent dans les recherches universitaires. En prenant en compte ces travaux et les résultats déjà capitalisés, nous nous proposons d’interroger ici la problématique suivante : dans le rapport à une norme linguistique, que signifie, en littérature, le fait de « bien écrire » et conjointement celui de « m..

Mythes et réalités de l’écriture

Depuis quelques années, l’étude des interactions entre les langues et des divers phénomènes linguistiques repérables dans le champ de l’écriture multilingue constitue un axe d’investigation récurrent dans les recherches universitaires. En prenant en compte ces travaux et les résultats déjà capitalisés, nous nous proposons d’interroger ici la problématique suivante : dans le rapport à une norme linguistique, que signifie, en littérature, le fait de « bien écrire » et conjointement celui de « m..