Éditeur(s) : HAL CCSD
Résumé : Different applications of linear elasticity in structural geology are presented in this thesis through the development of three types of numerical computer codes. The first one uses forward modeling to study displacement and perturbed stress fields around complexly faulted regions. We show that incorporating inequality constraints, such as static Coulomb friction, enables one to explain the angle of initiation of jogs in extensional relays. Adding heterogeneous material properties and optimizations, such as parallelization on multicore architectures and complexity reduction, admits more complex models. The second type deals with inverse modeling, also called parameter estimation. Linear slip inversion on faults with complex geometry, as well as paleo-stress inversion using a geomechanical approach, are developed. The last type of numerical computer code is dedicated to restoration of complexly folded and faulted structures. It is shown that this technique enables one to check balanced cross-sections, and also to retrieve fault chronology. Finally, we show that this code allows one to smooth noisy 3D interpreted faulted and folded horizons using geomechanics.
Différentes applications de l'élasticité linéaire en géologie structurale sont présentées dans cette thèse à travers le développement de trois types de codes numériques. Le premier utilise la modélisation directe pour étudier les déplacements et champs de contraintes autour de zones faillées complexes. On montre que l'ajout de contraintes inégalitaires, telles que la friction de Coulomb, permet d'expliquer l'angle d'initiation des dominos dans les relais extensifs. L'ajout de matériaux hétérogènes et d'optimisations, telles la parallélisation sur processeurs multi-coeurs ainsi que la réduction de complexité des modèles, permettent l'étude de modèles beaucoup plus complexes. Le second type de code numérique utilise la modélisation inverse, aussi appelée estimation de paramètres. L'inversion linéaire de déplacements sur les failles ainsi que la détermination de paléo-contraintes utilisant une approche géomécanique sont développées. Le dernier type de code numérique concerne la restauration de structures complexes plissées et faillées. Il est notamment montré qu'une telle méthode permet de vérifier l'équilibre de coupes géologiques, ainsi que de retrouver la chronologie des failles. Finalement, nous montrons que ce même code permet de lisser des horizons 3D faillés, plissés et bruités en utilisant la géomécanique.
https://tel.archives-ouvertes.fr/tel-00537899

tel-00537899
https://tel.archives-ouvertes.fr/tel-00537899
https://tel.archives-ouvertes.fr/tel-00537899/document
https://tel.archives-ouvertes.fr/tel-00537899/file/thesemaerten.pdf

Éditeur(s) : Acte du Conseil International pour l'Exploration de la mer, CM 1987/K:52
Résumé : La numération des larves d'huître dans le plancton renseigne les ostréiculteurs sur la date de pose des collecteurs. La technique utilisée est très ancienne (BOURY, 1928) ; pour chaque station trois prélèvements par traits de filets pendant 10 minutes sont effectués : deux en surface (filet 200 et filet 130) et un à 1 mètre de profondeur (filet 130). Une méthode par pompage avec mesure instantanée du volume d'eau filtrée a été mise au point (prélèvements en surface et à 1 mètre de profondeur, et rétention des véligères sur filets 200). La comparaison des deux techniques met en évidence l'inadaptation de l'ancienne méthode. Le choix de la porosité (70 µm pour les filets 200) est mal adapté à la récolte des larves D (stade 1) dont le nombre peut être sous estimé par un facteur 10 (distension des mailles par la traction sur les filets) ; à l'inverse l'utilisation des filets 130 (porosité 130 µm) lorsque la taille des véligères augmente, s' accompagne d'une surestimation du nombre de larves par mètre cube, (facteur de 1.6 à 2 4). La technique des traits de filets ne permet donc pas de ramener le nombre de larves prélevées à un volume d'eau déterminé. Les observations par pompage volumétrique montrent que les différents stades larvaires sont plus abondants à 1 m de profondeur de jour (68 % à 90 %), avec une légère tendance à la migration vers la surface la nuit (46 % à 64 %). La numération des larves dans le plancton pourrait donc être effectuée par pompage à l'aide d'un seul prélèvement par station, à 1 m de profondeur, avec rétention sur un filet de porosité 70 µm.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1987/acte-6444.PDF
http://archimer.ifremer.fr/doc/00000/6444/

Éditeur(s) : IEEE
Résumé : This paper aims at studying the quality of the sea surface salinity (SSS) retrieved from soil moisture and ocean salinity (SMOS) data in coastal areas. These areas are characterized by strong and variable SSS gradients [several practical salinity units (psu) on relatively small scales: the extent of river plumes is highly variable, typically at kilometric and daily scales. Monitoring this variability from SMOS measurements is particularly challenging because of their resolution (typically 30-100 km) and because of the contamination by the nearby land. A set of academic tests was conducted with a linear coastline and constant geophysical parameters, and more realistic tests were conducted over the Bay of Biscay. The bias of the retrieved SSS has been analyzed, as well as the root mean square (rms) of the bias, and the retrieved SSS compared to a numerical hydrodynamic model in the semirealistic case. The academic study showed that the Blackman apodization window provides the best compromise in terms of magnitude and fluctuations of the bias of the retrieved SSS. Whatever the type of vegetation cover, a strong negative bias, greater than 1 psu, was found when nearer than 36 km from the coast. Between 44 and 80 km, the type of vegetation cover has an impact of less than a factor 2 on the bias, and no influence further than 80 km from the coast. The semirealistic study conducted in the Bay of Biscay showed a bias over ten days lower than 0.2 psu for distances greater than 47 km, due to an averaging over various geometries (coastline orientation, swath orientation, etc.). The bias showed a weak dependence on the location of the grid point within the swath. Despite the noise on the retrieved SSS, contrasts due to the plume of the Loire River and the Gironde estuary remained detectable on ten-day averaged maps with an rms of 0.57 psu. Finally, imposing thresholds on the major axis of the measurements brought little improvement to the bias, whereas it increased the rms and- could lead to strong swath restriction: a 49-km threshold on the major axis resulted in an effective swath of 800-900 km instead of 1200 km. NOT CONTROLLED OCR
Transactions on geoscience an remote sensing IEEE (0196-2892) (IEEE), 2007-07 , Vol. 45 , N. 7 , P. 2061-2072

Droits : 2007 IEEE
http://archimer.ifremer.fr/doc/2007/publication-3643.pdf
DOI:10.1109/TGRS.2007.894934
http://archimer.ifremer.fr/doc/00000/3643/

Éditeur(s) : E.J. BRILL Leiden.
Résumé : Genus Janirella Bonnier, 1885, has numerous members in the North Atlantic Ocean (J. nanseni Bonnier, 1885; J. abyssicola Richardson, 1911; J. glabra Richardson, 1911; J. spongicola Hansen, 1916; J. lobata Richardson, 1908; J. laevis Hansen, 1916; J. vemae Menzies, 1962; J. priseri Chardy, 1972) as well as in the adjoining seas (J. bonnieri Stephensen, 1915 in the Mediterranean Sea and J. carribica Menzies, 1956 in the Caribbean Sea). Two new species have been added to this list, J. bocqueti sp. n. and J. laubieri sp. n., collected during the Noratlante cruise of the R.S. "Jean Charcot".
Le genre Janirella Bonnier, 1885, compte de nombreux représentants en Atlantique Nord (J. nanseni Bonnier, 1885 ; J. abyssicola Richardson, 1911 ; J. glabra Richardson, 1911 ; J. spongicola Hansen, 1916 ; J. lobata Richardson, 1908 ; J. laevis Hansen, 1916 ; J. vemae Menzies, 1962 ; J. priseri Chardy, 1972) ainsi que dans les mers adjacentes (J. bonnieri Stephensen, 1915 en Méditerranée et J. carribica Menzies, 1956 en mer des Caraïbes). A cette liste viennent s'ajouter deux espèces nouvelles, J. bocqueti sp. n. et J. laubieri sp. n., récoltées au cours de la campagne Noratlante du N.O. ,,Jean Charcot". [OCR NON CONTRÔLE]
Crustaceana (E.J. BRILL Leiden.), 1974 , Vol. 26 , N. 2 , P. 129-135

Droits : E.J. BRILL Leiden.
http://archimer.ifremer.fr/doc/1974/publication-5118.pdf
http://archimer.ifremer.fr/doc/00000/5118/

Éditeur(s) : HAL CCSD E Schweizerbart Science Publishers
Résumé : International audience
We present an electron tomography study of dislocations in deformed olivine single crystals, at ca. 0.5 T m, along two distinct orientations. The easiest slip systems are [001](100) and [001]{110}. Disorientating a single crystal away from easy glide conditions leads to massive cross-slip, which generates three-dimensional dislocations, and thus contributes to hardening. Fast motion of curved non-screw dislocation in those planes leaves long straight screw dislocations which bear lattice friction and control plastic strain. We have identified several hardening mechanisms. Non-screw [001] dislocations interact elastically to form dipoles. Recovery mechanisms leading to dipole annihilation are observed, but they are slow at those temperatures and produce numerous sessile loops. These loops represent obstacles for gliding dislocations. Interactions between dislocations and sessile loops produce sessile segments (super jogs), which efficiently impede dislocation motions.
ISSN: 0935-1221

hal-01277821
https://hal.archives-ouvertes.fr/hal-01277821
DOI : 10.1127/ejm/2015/0027-2481

Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
The outstanding exposure of deformation bands in a multilayer sequence of the Orange quarry, Provence, France, motivates a study investigating the development and controls of deformation band geometries by field mapping combined with finite element modeling. Field mapping yields new insights into angular relations between, and evolution of, the deformation bands as well as provides input parameters for the setup and boundary conditions of the numerical simulations using ADELI 2D. In particular, reverse-sense deformation bands are found to have developed within three of the four exposed layers of the multilayer stack with similar orientations to bedding, indicating layer-parallel contraction. Numerical simulations, carried out as a parametric study to investigate the influence on deformation band development and geometry, successfully reproduce the sequential development of deformation bands in the three layers as seen in the field as well as recreate the observed angular geometries of similar to 39 degrees to the maximum compression. This angular relationship is put into context with observations from other field studies and theoretical values to explore controls of deformation band orientations. Furthermore, band localization is impeded in the model by increased layer cohesive strength, demonstrating the importance of host-rock property variations on where localization of bands within the multilayer sequence. Results from both field investigation and numerical simulations are consistent with regional tectonics, where the strata underwent gentle folding due to thrust faulting at depth, and bring further insight into the development and geometry of deformation bands in both extensional and contractional tectonic regimes.
ISSN: 0148-0227

hal-00639452
https://hal.archives-ouvertes.fr/hal-00639452
DOI : 10.1029/2011JB008365

Éditeur(s) : Wiley-blackwell
Résumé : The reef fauna connectivity of the West Indian Ocean (WIO) is one of the least studied globally. Here we use genetic analyses of the grouper Epinephelus merra (Bloch 1793) to determine patterns of connectivity and to identify barriers to dispersal in this WIO marine area. Phylogeographic and population-level analyses were conducted on cytochrome b sequences and microsatellites (13 loci) from 557 individuals sampled in 15 localities distributed across the West Indian Ocean. Additional samples from the Pacific Ocean were used to benchmark the WIO population structure. The high level of divergence revealed between Indian and Pacific localities (of about 4.5% in sequences) might be the signature of the major tectonic and climatic changes operating at the Plio-Pleistocene transition, congruently with numerous examples of Indo-Pacific speciation. In comparison, the E. merra sequences from the Indian Ocean constitute a monophyletic clade with a low average genetic distance (d < 0.5%). However both genetic markers indicated some structure within this ocean. The main structure revealed was the isolation of the Maldives from the WIO localities (a different group signature identified by clustering analysis, great values of differentiation). Both marker types reveal further significant structure within the WIO, mainly the isolation of the Mascarene Islands (significant AMOVA and isolation-by-distance patterns) and some patchy structure between the northernmost localities and within the Mozambique Channel. The WIO genetic structure of E. merra appeared congruent with main biogeographic boundaries and oceanographic currents.
Marine Ecology-an Evolutionary Perspective (0173-9565) (Wiley-blackwell), 2015-09 , Vol. 36 , N. 3 , P. 447-461

Droits : 2014 Blackwell Verlag GmbH
http://archimer.ifremer.fr/doc/00189/30046/28566.pdf
DOI:10.1111/maec.12153
http://archimer.ifremer.fr/doc/00189/30046/

Éditeur(s) : HAL CCSD AGU and the Geochemical Society
Résumé : International audience
We propose a new thermomechanical numerical model of mid-ocean ridge accretion aimed at investigating asymmetric spreading rates, diverse configurations of lens and sill magma injections, crystallization and depth, and on- and off-axis patterns of hydrothermal cooling. The numerical algorithm iteratively resolves temperature and motion equations until it reaches a stationary solution. The motion equation was written in a vorticity-stream function formalism, with boundary and internal conditions applied to the stream function to impose the style of magma injection. Unlike in previous models, our model does not assume an a priori shape for the temperature field, which is initiated by an initial half-space cooling according to the left and right spreading rates. Complex patterns of hydrothermal cooling are simulated by enhanced thermal diffusivity. The model succeeds in describing the dynamic and thermal effects of spreading rates, the style of magma intrusion, and the hydrothermal cooling. Accurate descriptions of these are essential to study the cooling histories of crustal rocks and geophysical observables.
ISSN: 1525-2027

hal-00413118
https://hal.archives-ouvertes.fr/hal-00413118
DOI : 10.1029/2008GC002270

Éditeur(s) : HAL CCSD Ocean Drilling Programm
Résumé : This paper provides a summary of postcruise scientific results from Ocean Drilling Program (ODP) Leg 209 available to date, building upon shipboard observations and syntheses summarized in the Leg 209 Initial Results volume. During Leg 209, 19 holes were drilled at 8 sites along the Mid-Atlantic Ridge from 14°43´ to 15°44´N, mainly in residual mantle peridotite intruded by gabbroic rocks, in order to understand the tectonic and structural processes responsible for formation of oceanic lithosphere with abundant residual peridotite exposed on the seafloor coupled with a relatively low proportion of volcanic rocks. Based on proportions of recovered lithologies, the entire area may be underlain by mantle peridotite with ~20%–40% gabbroic intrusions and impregnations. Impregnated peridotites with olivine + two pyroxenes + plagioclase + spinel that apparently formed in equilibrium probably record crystallization from primitive mid-ocean-ridge basalt at pressures of 0.5–0.6 GPa. Metamorphic equilibria record isobaric cooling to ~1100°C at this pressure. Thus, the conductively cooled thermal boundary layer beneath the Mid-Atlantic Ridge in this region is >15 km thick. Combined crystallization and reaction with residual peridotite formed a series of impregnated peridotites recording increasing Na content at nearly constant Mg#; this process could explain some of the variation in fractionation-corrected Na (e.g., Na = 8.0) observed in mid-ocean-ridge basalts. Clinopyroxene textures and compositions record such impregnation processes, and they are particularly well documented for Site 1274. Other Leg 209 gabbroic rocks formed from extensive crystallization of highly evolved melts, indicating that a substantial proportion of melt entering the thermal boundary layer crystallizes entirely beneath the seafloor, with no volcanic equivalent. Alteration of peridotites occurred over a range of temperatures and is the result of three distinct processes: rock-dominated serpentinization with formation of brucite in olivine-rich lithologies, fluid-dominated serpentinization with formation of magnetite and no brucite, and fluid-dominated talc alteration with addition of SiO2 as well as H2O and oxygen. The latter two processes also exhibit detectable trace element metasomatism that is distinct in its character from the igneous impregnation described in the previous paragraph. Microstructures show that most residual peridotites were not ductilely deformed at temperatures less than ~1200°C. Structural and paleomagnetic data require tectonic rotations of relatively undeformed blocks; some rotations probably exceeded 60° around nearly horizontal axes parallel to the rift axis. Rotations occurred along several generations of high-temperature mylonitic shear zones extending deeper than 15 km depth and numerous faults at lower temperature. Early formed shear zones and faults were passively rotated around later features; such a process could have produced low-angle fault surfaces without slip on low-angle faults. This region provides end-member examples of processes that are common at many or most slow-spreading ridges. Osmium isotope ratios indicate an ancient history of depletion for residual peridotites from the 14°–16°N region along the Mid-Atlantic Ridge. Though depleted Os isotope ratios in peridotite have been reported elsewhere along the global ridge system, the values from this region are among the most depleted. In general, Os isotope ratios from mid-ocean-ridge basalts are systematically more radiogenic than Os isotope ratios from ridge peridotite samples, suggesting a polygenetic heterogeneous source for mid-ocean-ridge basalts. Geochemical studies of zircons from Leg 209 gabbroic rocks and impregnated peridotites, together with other ridge and arc-related zircons, indicate that ridge zircons have systematically lower fractionation-corrected U and Th concentrations compared to arc zircons. This observation provides a tool for interpreting the tectonic provenance of ancient detrital zircons and indicates an arclike provenance for Hadean detrital zircons. Geobiological studies and aerobiological studies were also undertaken during Leg 209. The geobiological work found no measurable microbial enhancement of olivine dissolution rate, possibly because the samples from Leg 209 were sterile. The aerobiological study determined that dust from North Africa, collected from the derrick of the JOIDES Resolution during Leg 209, contains a variety of abundant microorganisms.
Proceedings ODP, scientific results, 209

hal-00407966
https://hal.archives-ouvertes.fr/hal-00407966
DOI : 10.2973/odp.proc.sr.209.001.2007

Éditeur(s) : Springer
Résumé : The distribution of summer phytoplankton across the Straits of Magellan (SOM) was studied with the aims of tracing differences among the distinct subregions of the area and contributing to the knowledge of its biodiversity. Samples collected at 25 stations were observed and counted in light microscopy. Selected samples were observed with transmission electron microscopy. The main unifying feature of the phytoplankton in the SOM was the high abundance and numerical dominance of small-sized (<10 μm) eukaryotic species, among which coccoid cells of <3 μm size were predominant (56.2 ± 30.6 of the total phytoplankton abundance). They mostly belonged to the prasinophyte Pycnococcus provasolii, which was abundant (0.8–6,834 cells × 103 ml−1) at all stations with the exception of those in proximity to the Atlantic entrances, where it was not recorded. Small-sized (<3 and 3–5 μm) diatoms (Minidiscus trioculatus, Lennoxia faveolata and other undetermined centric species) attained high densities (<3,757 cells 103 ml−1) especially at stations of the Patagonian sectors, whereas microplanktonic diatoms were only found at the two entrances of the Straits. Dinoflagellates were constituted mainly by >10 μm forms in the Andean subregion and <10 μm naked species in the Patagonian subregion, contributing up to 75.9 and 41.8% of the total carbon in these two areas, respectively. In the Patagonian subregion, flagellates mainly constituted by <5 μm forms and by cryptomonads <10 μm comprised up to 53.9% of the total biomass. Several species identified in this study have never been reported in other investigations in the SOM, while others, including Pycnococcus provasolii and Lennoxia faveolata, have rarely been recorded elsewhere. Overall, the summer phytoplankton of the Straits does not resemble that of any other region of the world’s seas. Although some of the predominant species might have been overlooked elsewhere, their abundance and relative importance apparently constitute a distinctive feature of the SOM.
Polar Biology (0722-4060) (Springer), 2011 , Vol. 34 , N. 9 , P. 1269-1284

Droits : The Author(s) 2010. This article is published with open access at Springerlink.com
http://archimer.ifremer.fr/doc/00026/13722/10828.pdf
DOI:10.1007/s00300-010-0937-2
http://archimer.ifremer.fr/doc/00026/13722/

Éditeur(s) : HAL CCSD Global Science Press
Résumé : International audience
In this paper, the authors present two different time-discretization schemes combined with a finite-volume space discretization for the incompressible Navier-Stokes equations. They show that the collocated space discretization, usually used with a projection method, can also be extended to other time discretizations over previous projection methods, like the splitting methods. The main advantage of this splitting method is that the pressure approximation is truly of second order. In the first and second parts of this article, two different time-discretization schemes are considered with a collocated space discretization and it is explained how the unknown can be correctly coupled. Numerical simulations are presented in the last part. Tests of spatial and time accuracies are made. The numerical results when the Navier-Stokes problem is solved are shown, in the model problem of the driven cavity.
ISSN: 1815-2406

hal-00730191
https://hal.archives-ouvertes.fr/hal-00730191

Éditeur(s) : Gauthier-Villars
Résumé : A fish community was studied in Terminos Lagoon, Mexico over a one year period. Diurnal (24-h) and seasonal variations of several diversity indices - density, biomass, frequency and numerical abundance - were statistically related to changes in salinity, temperature, tide, and light periods. There were seasonal variations in all parameters of the community. The ecological parameters of the fish community remained high, reflecting a daily and seasonal succession of dominant fish species. The similarity in nichthemeral and seasonal changes exhibited by certain assemblages of species indicates that some dominant groups are influenced more by light period than by tidal stage. Community inhabitants and consumers of different trophic categories were seasonally quantified. Cyclical visitors (49%) and second-order consumers (49%) were dominant throughout the entire year. Twenty species were quantitatively important in terms of frequency, biomass and numerical abundance.
Oceanologica Acta, Special issue (0399-1784) (Gauthier-Villars), 1982

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00246/35702/34211.pdf
http://archimer.ifremer.fr/doc/00246/35702/

Résumé : Hierba bulbífera escamosa, bulbos divididos de hasta 10 cm de diámetro, tunicados. Hojas basales, de hasta 40 cm, huecas, semicirculares en sección transversal. Escapo de hasta 60 cm de altura. Abundantes flores moradas o casi blancas, agrupadas en una umbela grande, esférica, con 2 a 3 brácteas. Fruto capsular. Raras veces llega a producir semillas.
Herbe bulbeuse à écailles, bulbes divisés pouvant atteindre 10 cm de diamètre, tuniqués. Feuilles basales, pouvant atteindre 40 cm, creuses, semi-circulaires en section transversale. Hampe florale pouvant atteindre 60 cm de haut. Fleurs abondantes, violettes ou presque blanches, groupées en une grande ombelle sphérique, de 2 à 3 bractées. Fruit capsulaire. Produit rarement des graines.
Bulbous and scaly herb; bulbs up to 10 cm in diameter, tunicated.  Leaves basal, up to 40 cm in length, hollow, semi-circular or in cross-section.  Scape up to 60 long.  Flowers numerous, purple or almost white, grouped in large, spherical umbel, with 2 to 3 bracts.  Fruit capsular.
Oriunda de Asia occidental es extensamente cultivada en el mundo entero.
Originaire d&rsquo;Asie occidentale; sa culture est très répandue dans le monde entier.
Native to western Asia, widely cultivated around the world.

http://www.tramil.net/fototeca/plant408

Éditeur(s) : HAL CCSD EDP Sciences
Résumé : International audience
In this work, we point out and apply some ideas for the numerical simulation by multi- level schemes of several wave equations including dispersive (Korteweg de Vries) and dissipative ones (Kuramoto-Sivashinski). We start from the approach developed for dissipative equations decomposing the solution into large (Y) and small (Z) scales, and we show that it is necessary to have a regularization in time to allow stable numerical treatment of Y and Z which are here generated using hierarchical processes such as Wavelets, Incremental Unknowns or Fourier.
ISSN: 1270-900X

hal-00768332
https://hal.archives-ouvertes.fr/hal-00768332
https://hal.archives-ouvertes.fr/hal-00768332/document
https://hal.archives-ouvertes.fr/hal-00768332/file/esaim_proc_2009_v27.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
This paper aims to present an overview on the influence of rheological heterogeneity and mechanical anisotropy on the deformation of continents. After briefly recapping the concept of rheological stratification of the lithosphere, we discuss two specific issues: (1) as supported by a growing body of geophysical and geological observations, crust=mantle mechanical coupling is usually efficient, especially beneath major transcurrent faults which probably crosscut the lithosphere and root within the sublithospheric mantle; and (2) in most geodynamic environments, mechanical properties of the mantle govern the tectonic behaviour of the lithosphere. Lateral rheological heterogeneity of the continental lithosphere may result from various sources, with variations in geothermal gradient being the principal one. The oldest domains of continents, the cratonic nuclei, are characterized by a relatively cold, thick, and consequently stiff lithosphere. On the other hand, rifting may also modify the thermal structure of the lithosphere. Depending on the relative stretching of the crust and upper mantle, a stiff or a weak heterogeneity may develop. Observations from rift domains suggest that rifting usually results in a larger thinning of the lithospheric mantle than of the crust, and therefore tends to generate a weak heterogeneity. Numerical models show that during continental collision, the presence of both stiff and weak rheological heterogeneities significantly influences the large-scale deformation of the continental lithosphere. They especially favour the development of lithospheric-scale strike-slip faults, which allow strain to be transferred between the heterogeneities. An heterogeneous strain partition occurs: cratons largely escape deformation, and strain tends to localize within or at the boundary of the rift basins provided compressional deformation starts before the thermal heterogeneity induced by rifting are compensated. Seismic and electrical conductivity anisotropies consistently point towards the existence of a coherent fabric in the lithospheric mantle beneath continental domains. Analysis of naturally deformed peridotites, experimental deformations and numerical simulations suggest that this fabric is developed during orogenic events and subsequently frozen in the lithospheric mantle. Because the mechanical properties of single-crystal olivine are anisotropic, i.e. dependent on the orientation of the applied forces relative to the dominant slip systems, a pervasive fabric frozen in the mantle may induce a significant mechanical anisotropy of the whole lithospheric mantle. It is suggested that this mechanical anisotropy is the source of the so-called tectonic inheritance, i.e. the systematic reactivation of ancient tectonic directions; it may especially explain preferential rift propagation and continental break-up along pre-existing orogenic belts. Thus, the deformation of continents during orogenic events results from a trade-off between tectonic forces applied at plate boundaries, plate geometry, and the intrinsic properties (rheological heterogeneity and mechanical anisotropy) of the continental plates.
ISSN: 0040-1951

hal-01389719
http://hal.univ-reunion.fr/hal-01389719
http://hal.univ-reunion.fr/hal-01389719/document
http://hal.univ-reunion.fr/hal-01389719/file/vauchez_etal_rheology_1998_hal.pdf
DOI : 10.1016/S0040-1951(98)00137-1

Éditeur(s) : Pergamon-elsevier Science Ltd
Résumé : The south-west lagoon of New Caledonia is a wide semi-open coral reef lagoon bounded by an intertidal barrier reef and bisected by numerous deep inlets. This paper synthesizes findings from the 2000-2008 French National Program EC2CO-PNEC relative to the circulation and the transport of suspended particles in this lagoon. Numerical model development (hydrodynamic, fine suspended sediment transport, wind-wave, small-scale atmospheric circulation) allowed the determination of circulation patterns in the lagoon and the charting of residence time, the later of which has been recently used in a series of ecological studies. Topical studies based on field measurements permitted the parameterisation of wave set-up induced by the swell breaking on the reef barrier and the validation of a wind-wave model in a fetch-limited environment. The analysis of spatial and temporal variability of suspended matter concentration over short and long time-scales, the measurement of grain size distribution and the density of suspended matter (1.27 kg 1(-1)), and the estimation of erodibility of heterogeneous (sand/mud, terrigenous/biogenic) soft bottoms was also conducted. Aggregates were shown to be more abundant near or around reefs and a possible biological influence on this aggregation is discussed. Optical measurements enabled the quantification of suspended matter either in situ (monochromatic measurements) or remotely (surface spectral measurements and satellite observations) and provided indirect calibration and validation of a suspended sediment transport model. The processes that warrant further investigation in order to improve our knowledge of circulation and suspended sediment transport in the New Caledonia lagoon as well as in other coral reef areas are discussed, as are the relevance and reliability of the numerical models for this endeavour.
Marine Pollution Bulletin (0025-326X) (Pergamon-elsevier Science Ltd), 2010 , Vol. 61 , N. 7-12 , P. 269-296

Droits : 2010 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/00014/12526/9401.pdf
DOI:10.1016/j.marpolbul.2010.06.023
http://archimer.ifremer.fr/doc/00014/12526/

Éditeur(s) : HAL CCSD
Résumé : International audience
Workshop Satellite Meetings ICIAM'2011
Vancouver, Canada

hal-00770279
https://hal.univ-antilles.fr/hal-00770279

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : L’objectif de ce numéro de la Revue Etudes Caribéennes est d’ouvrir une réflexion sur le concept de luxe, d’investir le luxe dans tous ses états. Il s’agit d’interroger les fondements du luxe, de la théorie à la matérialité, de la fabrication à la consommation, entre distinction provocante et esthétisation des genres de vie. Dans le cadre de ce numéro thématique, le luxe est envisagé dans une approche pluridisciplinaire, de la philosophie à la sociologie, de l’économie à l’aménagement du territoire … Les contributions pourront aborder le luxe sous un angle spécifique (économie du luxe, le luxe à travers l’histoire), traiter une dimension particulière du luxe, à travers un produit emblématique ou la construction de territoires singuliers (les territoires du luxe). Une attention particulière sera portée à l’industrie du luxe avec ses grandes marques et ses logiques de création et de production. Enfin, le luxe existe à travers la construction de ses légendes qui sont autant de signes distinctifs qui stimulent les consommateurs occasionnels et exclusifs. Les thématiques privilégiées seront : 1. Le concept du luxe à travers les différents champs disciplinaires (« consommation ostentatoire », « distinction provocante », « esthétisation des comportements », « marché-jugement ») 2. Le luxe dans le temps (entre sacré et ostentatoire, la signification du luxe, les mythes du luxe) 3. Le luxe et la création (les objets qui consacrent le luxe, de la création à la construction de la légende) 4. L’industrie du luxe (haute couture, joaillerie, spiritueux … griffes et grandes marques du luxe) 5. L’économie du luxe (le luxe en période de crise, l’économie des singularités) 6. Le luxe dans le champ du tourisme (l’hôtellerie de luxe, les destinations du tourisme de luxe) 7. La durabilité du luxe, entre renouvellement et éternité This issue of “Revues Etudes Caribéennes” aims to reflect upon the concept of luxury, to invest the luxury in all its states. It comes to question the foundations of luxury, from the theory to the materiality, from the manufacture to the consumption, between provocative distinction and aesthetization in all walk of life. Within the context of this thematic issue, luxury is envisaged a multidisciplinary approach, ranging from philosophy to sociology, from the economy to the development of the territory... Imputs may approach luxury a specific angle (economics of luxury, the luxury throughout history). They can treat a particular dimension of luxury, through an emblematic product or construction of luxury territories. Special attention will be paid to the luxury industry with its brands and its logic of creation and production. Finally, luxury exist through the construction of its legends which are formed from many distinctive indicators that stimulate both the casual and the exclusive consumers. The priorities themes will be: 1. The concept of luxury across the different disciplinary fields ('conspicuous consumption', 'provocative distinction", 'aestheticization of behaviour', and 'market-judgement') 2. Luxury in time (between the sacred and ostentatious, the meaning of luxury, the myths of luxury) 3. Luxury and Creation (objects dedicated to luxury, from the creation to the construction of the legend) 4. Luxury industry (haute couture, jewelry, spirits... claws and luxury brands) 5. The economy of luxury (luxury during economic crisis, and the economy of singularities) 6. Luxury in tourism (luxury hotels, luxury destinations) 7. The sustainability of luxury, between renewal and eternity El objetivo de este número de la Revista Estudios Caribeños es de abrir una reflexión sobre el concepto de lujo, de invertir el lujo en todos sus estados. Se trata de interrogar los fundamentos del lujo, de la teoría a la materialidad, de la fabricación a la consumición, entre distinción provocativa y formas de esteticismo de la vida. En este número temático, el lujo está considerado en un enfoque pluridisciplinar, de la filosofía a la sociología, de la economía a planificación del territorio…Las contribuciones podrán abordar el lujo sobre un ángulo específico (economía del lujo, el lujo a través de la historia), tratar una dimensión particular del lujo, a través de un producto emblemático o la construcción de territorios singulares (los territorios del lujo). Una atención particular será llevada a la industria del lujo con sus grandes marcas y lógicas de creación y de producción. En fin, el lujo existe a través de la construcción de sus leyendas que son tantos signos distintivos que estimulan los consumidores ocasionales y exclusivos. Los temas privilegiados serán: 1. El concepto del lujo a través de los diferentes campos disciplinarios (« consumación ostentosa », « distinción provocadora », « estetización de comportamientos, «juicio del mercado « ) 2. El lujo en el tiempo (entre sagrado y ostentatorio, el significado del lujo, los mitos del lujo) 3. El lujo y la creación (los objetos que consagran el lujo, de la creación a la construcción de la leyenda) 4. La industria del lujo (alta costura, joyería, espiritoso… uñas y grandes marcas del lujo) 5. La economía del lujo (el lujo en período de crisis, la economía de las singularidades) 6. El lujo en el campo del turismo (la hostelería de lujo, las destinaciones del turismo de lujo) 7. La duración del lujo, entre renovación y eternidad

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.7310
http://journals.openedition.org/etudescaribeennes/7310

Éditeur(s) : HAL CCSD Springer Optimization and Its Applications, Vol. 49
Résumé : International audience
Fixed-Point Algorithms for Inverse Problems in Science and Engineering

hal-00756766
https://hal.archives-ouvertes.fr/hal-00756766

Éditeur(s) : HAL CCSD
Résumé : International audience
This paper deals with variational inclusions of the form 0 2 f(x) + g(x) K where f is smooth function from a re exive Banach space X into a Banach space Y , g is a Lipschitz function from X into Y and K is a nonempty closed convex cone in the space Y . We show that the previous problem can be solved by an extension of the Zincenko's method which can be seen as a perturbed Newton's method. Numerical results are given at the end of the paper.
Revista Investigacion Operacional

hal-00924143
https://hal.archives-ouvertes.fr/hal-00924143