Éditeur(s) : Université des Antilles. Service commun de la documentation University of West Indies, Barbados
Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS
Description : Mulch application of Sargassum seaweed (Sargassum spp.) to soil can help to reduce beach contamination in the Caribbean Region while providing beneficial horticultural effects. This study investigated the effects of fresh Sargassum mulch on soil properties and plant growth in a test crop of tomato (Solanum lycopersicum L. â? ? HA 3019â? TM). Fresh Sargassum material (washed and unwashed) was applied as mulches (0, 5 and 8cm thick) to small field plots one week after transplanting of 3-week-old seedlings. The mulch material was raked away from the plots after three weeks exposure. Observations on soil moisture, electrical conductivity, pH and biological activity, and plant growth were made at 1 to 2-week intervals over a 6-week period with additional soil measurements after 10 weeks. Soil biological activity (respiration) was increased by the Sargassum mulch with values being similar for the 5cm and 8cm mulch layers. Soil moisture content, pH and electrical conductivity (EC) were increased as the mulch layer increased and EC values were only marginally reduced by Sargassum washing. An increase in plant growth compared to the control treatment was noted only in the washed Sargassum treatments. Potential benefits of Sargassum seaweed mulches on soil properties and plant growth can be nullified due to soil salinization effects.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V16269
V16269

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.
D20-007

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.
D29-009

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa
Lafayette Street

Droits : All rights reserved. 2005.
D20-008

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.
D29-014

Éditeur(s) : HAL CCSD Integrated Ocean Drilling Program
Résumé : In this report we present the results of laboratory measurements carried out to explore the electrical properties of gabbroic and troctolitic samples from Integrated Ocean Drilling Program (IODP) Hole U1309D in the Atlantis Massif, an oceanic core complex located at 30°N on the Mid-Atlantic Ridge. Oceanic core complexes are presumably localized in portions of heterogeneous oceanic crust that are relatively rich in igneous rocks and are the locus of significant hydrothermal activity. Electrical properties of igneous rocks are used to discuss the rocks' porosity structure as a function of mineralogy, alteration processes, and deformation. Electrical properties of the gabbroic suites sampled during IODP Expedition 304/305 can contribute to the understanding of these processes in the Atlantis Massif. We present the full suite of electrical data together with density and porosity measurements on the same suite of samples.
ISSN: 1930-1014

hal-00464179
https://hal.archives-ouvertes.fr/hal-00464179
DOI : 10.2204/iodp.proc.304305.204.2009

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.
D29-0015

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Previous work has demonstrated that geoelectrical measurements, acquired either along the Earth’s surface or in boreholes, can be sensitive to the presence of fractures. However, a lack of numerical approaches that are well suited to modelling electric current flow in fractured media prevents us from systematically exploring the links between geoelectrical measurements and fractured rock properties. To address this issue, we present a highly computationally efficient methodology for the numerical simulation of geoelectrical data in 2.5-D in complex fractured domains. Our approach is based upon a discrete-dual-porosity formulation, whereby the fractures and rock matrix are treated separately and coupled through the exchange of electric current between them. We first validate our methodology against standard analytical and finite-element solutions. Subsequent use of the approach to simulate geoelectrical data for a variety of different fracture configurations demonstrates the sensitivity of these data to important parameters such as the fracture density, depth, and orientation.
ISSN: 0956-540X

hal-01622151
https://hal.archives-ouvertes.fr/hal-01622151
https://hal.archives-ouvertes.fr/hal-01622151/document
https://hal.archives-ouvertes.fr/hal-01622151/file/sanzGJI2017.pdf
DOI : 10.1093/gji/ggx080

Éditeur(s) : HAL CCSD
Résumé : The presence of biological matter (biofilms) in deep geological sites for storage of, for instance, toxic elements or groundwater in aquifers was clearly proved. That biomass triggers physical and chemical processes which greatly modify the durability and the sustainability of the sites. These processes, mainly from oxidative/reductive reactions, are poorly understood. This is mainly due to the fact that former studies were done at the macroscopic level far away from the micrometric scale where relevant processes induced by bacteria take place. Investigations at microscopic level are needed. Thus, we developed an experimental set-up based on the combined use of optical microscopy (transmission), atomic force microscopy (AFM) and electrical and electro-chemical AFM microscopy (EC_AFM) in order to get simultaneous information on topographic and electro-chemical processes. The first highly sensitive step was to use AFM with biological samples in liquid environment: wepresent here a study about AFM imaging of living, moving or self-immobilized bacteria, in their genuine physiological liquid medium and in true in vivo conditions. No external immobilization protocol, neither chemical nor mechanical was needed. For the first time, the native gliding movements of Gram negative Nostoc cyanobacteria upon the surface were studied by AFM. AFM height and mechanical stiffness data were simultaneously acquired. From these, mechanical parameters, inner turgor pressure and Young modulus, were derived for different bacterial species (Anabaenopsis circularis, Rhodococcus wratislaviensis). Our study revealed that AFM imaging is thus possible on moving living species. These results open a large window on new studies of both dynamical phenomena of practical and fundamental interests such as the formation of biofilms and dynamic properties of bacteria in real physiological conditions. The second delicate step was to combine AFM and optical measurements with electrical ones. We mounted a new experimental set-up coupling real-time (i) monitoring of optical properties as the optical density (OD) evolution related to bulk bacterial growth in liquid or as the counting of number of bacteria adhering on the surface of the sample as well and (ii) electrical and electrochemical measurements. Furthermore, these results will shortly be applied to the optimized monitoring of the in-situ activity of bacteria consuming oil pollutants, following this way, in real-time, the bioremediation of an oilcontaminated soil (ANR ECOTECH_BIOPHY program).
La présence de matière biologique (biofilms) dans les sites de stockage géologique profond, d'éléments toxiques ou encore de l'eau potable des aquifères est maintenant clairement démontrée. Cette biomasse est à l'origine de processus physiques et chimiques qui modifient considérablement la durabilité et la pérennité des sites concernés. Ces processus, principalement de type oxydo-réductif, sont encore mal compris. Ceci est principalement dû aux méthodes d'investigation, principalement macroscopiques, loin de l'échelle micrométrique caractéristique des bactéries. Seules des études, basées sur des méthodes d'investigation locale, peuvent apporter les informations requises. Ainsi, nous avons développé un dispositif expérimental basé sur l'utilisation combinée de la microscopie optique (en transmission), la microscopie à force atomique (AFM) et la microscopie AFM en mode électrique et électrochimique (EC_AFM) afin d'obtenir des informations simultanées sur la topographie de l'échantillon et sur les processus électrochimiques à l'échelle des bactéries. La première étape sensible consistait à utiliser l'AFM sur des échantillons biologiques en milieu liquide: nous présentons ici les résultats de l'imagerie AFM en milieu liquide de plusieurs types de bactéries dans leurs conditions physiologiques naturelles (conditions in vivo). Aucun protocole d'immobilisation, ni chimique ni mécanique, n'a été nécessaire; et pour la première fois, les mouvements de reptation de cyanobactéries Nostoc ont été étudiés par l'AFM. Les études AFM ont permis d'acquérir des données topographiques mais aussi mécaniques : nous avons pu ainsi mesurer le module d'Young, la pression de turgescence de différentes souches bactériennes (Anabaenopsis circularis, Rhodococcus wratislaviensis). Cette étude complète, a révélé que l'imagerie AFM est donc possible sur des espèces vivantes en mouvement. Ces résultats ouvrent une grande fenêtre sur de nouvelles études d'intérêts tels que la formation de biofilms et les propriétés dynamiques de bactéries dans des conditions physiologiques réelles. La deuxième étape délicate était de combiner l'AFM aux mesures optiques et électriques. Nous avons développé un nouveau dispositif expérimental permettant (i) le suivi de l'évolution de la croissance bactérienne par la mesure des propriétés optiques comme la densité optique DO (pour le développement bactérien en volume - milieu planctonique) , ou l'analyse de l'image du substrat par comptage du nombre de bactéries sur la surface de l'échantillon (biofilm), et (ii) les mesures électriques et électrochimiques. L'ensemble de ces résultats sera prochainement appliqué au développement de nouveaux outils de surveillance d'une biodépollution de terrain contaminé par les hydrocarbures, par le suivi in situ et en temps réel de l'activité de bactéries dépolluantes (ECOTECH_BIOPHY ANR).
https://tel.archives-ouvertes.fr/tel-01044714

tel-01044714
https://tel.archives-ouvertes.fr/tel-01044714
https://tel.archives-ouvertes.fr/tel-01044714/document
https://tel.archives-ouvertes.fr/tel-01044714/file/theseDhahri2013.pdf

Éditeur(s) : HAL CCSD
Résumé : Geothermal energy is considered as a green and infinite energy source at human scale. Currently, the yield of geothermal power plants is limited to temperatures of the operating fluid which 350 °C. From tectonic and volcanic activity at mid-ocean ridges, Iceland is a location where supercritical fluid extraction (T> 375 °C) can considered for the near future. Exploiting such fluids could theoretically multiply by a factor of ten the electrical power delivered by geothermal wells. Can such fluids circulate at the base of brittle oceanic crust? This work investigates the petrophysical properties of basalts in order to constrain geophysical observations in Iceland and predict the behavior of very high temperature geo-hydrothermal reservoirs. The first approach consisted in studying the physical properties of rocks that have hosted deep hydrothermal circulations at oceanic ridges. The study of these rocks at ODP Site 1256 shows that the porosity measured both in the field and in the lab is associated with amphibolite facies alteration minerals (T> 500 ° C). The second approach was to recreate in the laboratory the conditions of pressure, temperature and pore fluid pressure of high temperature to supercritical hydrothermal systems to predict the mechanical and electrical properties of basalts under these conditions. The mechanical results indicate that the brittle/ductile transition occurs at a temperature of about 550° C, where a strong permeability decrease is expected. The implementation and calibration of a new cell for measuring electrical conductivity at high temperature provide the first results for the interpretation of geophysical data. When applied to basaltic crustal conditions in Iceland, these results indicate that hydrothermal fluids could circulate, at least temporarily, in a supercritical state up to 5 km depth.
La géothermie est considérée comme une source d'énergie propre et inépuisable à échelle humaine. Actuellement, le rendement des centrales géothermiques est limité à l'exploitation de fluides de températures inférieures à 350 °C. L'association de l'activité tectonique et volcanique aux dorsales océaniques fait de l'Islande un lieu où l'extraction de fluides supercritiques (T> 375 °C) peut être envisagée. Cette exploitation pourrait multiplier par dix la puissance électrique délivrée par le système géothermal. Ces fluides peuvent-ils circuler dans la croûte océanique ? Ce travail propose de contraindre les observations géophysiques et de prédire le fonctionnement des réservoirs géo-hydrothermaux de très haute température par l'étude des propriétés physiques des basaltes. La première approche est focalisée sur l'étude de roches ayant accueilli une circulation hydrothermale par le passé. L'étude de ces roches au site ODP 1256, montre que leur porosité est associée à la présence de minéraux d'altération hydrothermale du facies amphibolite (T> 500 °C). La seconde approche a consisté à recréer, en laboratoire, les conditions des systèmes hydrothermaux, à très haute température, afin de prédire les propriétés mécaniques et électriques des basaltes dans ces conditions. Les résultats mécaniques indiquent que la transition fragile/ductile, souvent associée à une forte décroissance de perméabilité, intervient à une température d'environ 550 °C. La mise en place d'une cellule de mesure de la conductivité électrique de haute température a fourni les premiers résultats utiles à l'analyse des données géophysiques. Appliqués aux conditions de la croûte basaltique Islandaise, ces résultats indiquent que des fluides hydrothermaux pourraient circuler au moins transitoirement à l'état supercritique jusqu'à ~ 5 km de profondeur.
https://tel.archives-ouvertes.fr/tel-00591798

tel-00591798
https://tel.archives-ouvertes.fr/tel-00591798
https://tel.archives-ouvertes.fr/tel-00591798/document
https://tel.archives-ouvertes.fr/tel-00591798/file/THESE_MV_pro.pdf

Éditeur(s) : HAL CCSD American Association of Petroleum Geologists
Résumé : In reservoir engineering, hydrodynamic properties can be estimated from downhole electrical data using heuristic models (e.g., Archie and Kozeny-Carman's equations) relating electrical conductivity to porosity and permeability. Although proven to be predictive for many sandstone reservoirs, the models mostly fail when applied to carbonate reservoirs that generally display extremely complex pore network structures. In this article, we investigate the control of the three-dimensional (3-D) geometry and morphology of the pore network on the electrical and flow properties, comparing core-scale laboratory measurements and 3-D x-ray microtomography image analysis of samples from a Miocene reefal carbonate platform located in Mallorca (Spain). The results show that micrometer- to centimeter-scale heterogeneities strongly influence the measured macroscopic physical parameters that are then used to evaluate the hydrodynamic properties of the rock, and therefore, existing models might not provide accurate descriptions because these heterogeneities occur at scales smaller than those of the integration volume of the borehole geophysical methods. However, associated with specific data processing, 3-D imagery techniques are a useful and probably unique mean to characterize the rock heterogeneity and, thus, the properties variability.
ISSN: 0149-1423

hal-00950066
https://hal.archives-ouvertes.fr/hal-00950066
DOI : 10.1306/05221312134

Éditeur(s) : HAL CCSD
Résumé : International audience
This paper presents a microfluidic system, characterizing the red blood cell (RBC) deformability through its transit time in a microchannel, which dimensions reproducing blood microcirculation capillary. Electrodes are integrated within the microchannel for electrical measurements. The transit time is measured with the electrical blockade produced when the RBC squeezes in the microchannel (d = 5 μm diameter, while the cell diameter is 8 μm). In order todetermine most suitable electrical frequency range for the voltage applied to excitation electrodes, FEM numerical simulation of the bioimpedance is achieved and presented in this paper. We investigated the frequency response of the bioimpedance taking into account the electrode polarization, the dielectric properties of the medium, a single shell model for RBC and finally the RBC position within the microchannel.
Eurosensors
Paris, France

hal-01592142
https://hal.archives-ouvertes.fr/hal-01592142
DOI : 10.3390/proceedings1040517

Éditeur(s) : HAL CCSD
Résumé : National audience
New experimental data on electrical and anelastic properties of oceanic rocks at high pressures and temperatures are compared with the field data of seismic and electrical anomalies observed at oceanic spreading centers. The laboratory results of electrical conductivity and internal friction on gabbro and peridotites permit to estimate a degree of partial melting and maximum temperature in axial magma chambers (12-15% of melting at 1155-1165°C) and at the upper boundary of a source zone at the depth of 40-90 km (less than 5% of melting in the absence of pyroxene crystals and up to 11-14% in the pyroxene reach rocks at 1360-1370°C) at mid-oceanic ridges.
ISSN: 0934-6554

hal-01322920
http://hal.univ-reunion.fr/hal-01322920

Résumé : When Henry B. Plant brought the railroad to Tampa in 1884, he opened the door for many businesses to locate and flourish here. The railroad was at the center of the city's economy. From downtown it went to Port Tampa where one could board a Plant steamship to Jamaica, Cuba, New Orleans, Bermuda or other destinations. A spur of the rail line brought the train up to the west front of the hotel so guests could depart the train and walk directly into the lobby. The Tampa Bay Hotel cost approximately 2.5 million dollars to build and $500,000 to furnish. Consisting of 511 rooms, some of which were suites of 3-7 rooms, it provided a degree of luxury never before seen in Tampa. Most of the rooms had their own baths and all had electricity and telephones. In addition, guests were surrounded by a varied collection of furniture, porcelains, Venetian-style mirrors, and sculptures gathered by Mr. and Mrs. Plant in their travels in Europe. The Tampa Bay Hotel opened in 1891 amid wide fanfare and celebration. Henry Plant's dream was now a reality. The newspapers of the day described it as "brightly illuminated, filled with sumptuous decorations, thrilling music and graced with turrets, domes and minarets towering heavenward and glistening in the sun." It was a Victorian palace. The hotel was a lively place with balls, tea parties, and organized hunts during the winter social season. It was open seasonally from December to April in the 1890's. Once a guest arrived at the hotel, he needed to be entertained. Guests went wild game hunting as well as fresh and salt-water fishing. Water sports were also included like sailing, rowing, and canoeing. For the less adventuresome, there were bicycles, carriages, and rickshaws to ride you around the property. The hotel also offered golf, tennis, shuffleboard, billiards, and even a racetrack.
(Funding) Funded in part by the Institute for Museum and Library Services (IMLS), Ephemeral Cities Project.
Tampa |z 1271000 |2 ceeus
Hillsborough County |z 12057 |2 ceeus
United States of America -- Florida -- Hillsborough County -- Tampa

Droits : All rights reserved. 2005.
D29-013

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Wind energy production is very sensitive to turbulent wind speed. Thus rapid variation of wind speed due to changes in the local meteorological conditions can lead to electrical power variations of the order of the nominal power output, in particular when wind power variations on very short time scales, range at few seconds to 1 h, are considered. In small grid as they exist on islands (Guadeloupean Archipelago: French West Indies) such fluctuations can cause instabilities in case of intermediate power shortages. The developed analysis in [14] reveals three main classes of time series for the wind speed fluctuations. In this work, Probability Density Functions (PDFs) are proposed to fit the wind speed fluctuations distributions in each class. After, to simulate wind speed fluctuations sequences, we use a stochastic differential equation, the Langevin equation considering Gaussian turbulence PDF (class I), Gram–Charlier PDF (class II) and a mixture of gaussian PDF (class III). The statistical and dynamical properties of simulated wind sequences are close to those of measured wind sequences, for each class
ISSN: 0306-2619

hal-01527885
https://hal.archives-ouvertes.fr/hal-01527885
DOI : 10.1016/j.apenergy.2012.05.007

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) : HAL CCSD American Geophysical Union
Résumé : International audience
The hydraulic and electrical properties of pyroclastic rocks have been investigated in laboratory on a representative sampling of Montagne Pelée (Martinique, France) deposits with renewed interest in geophysical applications. This sampling covers all the lithologic units of this volcano: lava dome and lava flows, pumices from ash-and-pumice fall and flow deposits, lava blocks from block-and-ash flow and Peléean “nuées ardentes” deposits, scoriae from scoria flow deposits. The connected porosity varies over a wide range from 3 to 62%. The unconnected porosity is important only on pumices where it can reach 15%. The permeability covers more than 5 orders of magnitude, ranging from 10−16 to 35 × 10−12 m2. The higher values are obtained on lava blocks and the scoriae, even if these rocks are less porous than the pumices. The formation factor ranges from 7 to 1139. The transport properties of these rocks are slightly correlated with porosity. This indicates that these properties are not only controlled by the connected porosity. To connect the transport properties to the textural characteristics of the pore network of pyroclastic rocks, different models, based on geometrical considerations or percolation theory, were tested. The pore access radius distribution and the tortuosity control the transport properties of pyroclastic rocks. Consequently, the models (electric and hydraulic) based on the concept of percolation (e.g., the models of Katz and Thompson), apply better than the equivalent channel model of Kozeny-Carman. In addition, the difference in transport properties observed on lava blocks and pumices confirms that the mechanisms of degassing and vesiculation are different for these two types of rock.
ISSN: 2169-9313

hal-00310237
https://hal.archives-ouvertes.fr/hal-00310237
DOI : 10.1029/2006JB004385, 2007

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ODP (Ocean Drilling Program)/IODP (Integrated Ocean Drilling Program) Site 1256 is located on the Cocos Plate in the Eastern Equatorial Pacific Ocean, in a 15 Ma old oceanic lithosphere formed at the EPR during a period of superfast spreading (>200 mm/yr). ODP/IODP Hole 1256D reached for the first time the contact between sheeted dikes and underlying gabbros. It consequently offers a unique opportunity to study in situ, in present-day oceanic crust, the root zone of the sheeted dike complex. This root zone is a thin, 100 m thick boundary layer between the magmatic system (i.e., the axial melt lens, similar to 1100 degrees C), and the overlying high temperature hydrothermal system (<= 450 degrees C). The understanding of interactions within this boundary layer is critical to that of crustal processes along mid-ocean ridges.;This work focuses on the petrophysical characterization of the root zone of the sheeted dike complex in order to further constrain the hydrothermal circulation system in the vicinity of the axial melt lens, as recorded in non-granoblastic dikes, granoblastic dikes, and varitextured gabbros. The petrophysical properties were determined from sample measurements in the laboratory and were compared to in situ downhole geophysical probing. The porosity structure is bipolar, depending on lithology, resulting in a layered system. Non-granoblastic dikes are generally altered in the greenschist fades (similar to>250 degrees C) with relatively high and interconnected (cementation index m similar to 1.72, electrical tortuosity tau similar to 28.3) porosity (1.5%). In contrast, gabbros are retrogressively metamorphosed in the amphibolite (similar to>450 degrees C) and greenschist facies, with lower porosity (1.3%) that involves numerous fissures and cracks, resulting in a more connected medium (m similar to 1.58, tau similar to 11.8) than non-granoblastic dikes. These cracks are more abundant but also tend to close with increasing depth as indicated in downhole geophysical data. Porosity and alteration, as viewed from surface electrical conductivity, appear to be directly correlated.
ISSN: 0040-1951

hal-00544556
https://hal.archives-ouvertes.fr/hal-00544556
DOI : 10.1016/j.tecto.2010.07.013