La Quarantaine de Le Clézio et le vertige intertextuel

Le terme de vertige employé par M. Schneider convient particulièrement pour qualifier les jeux de l’intertextualité dans La Quarantaine de Le Clézio, même en la limitant aux textes effectivement cités. Intertexte essentiel, et trop évident, Robinson n’est nommé qu’une fois. L’épigraphe, la chanson du voleur et les références aux textes sacrés hindous rattachent le roman à l’Inde et à ses valeurs, qui constituent l’un des pôles signifiants, le côté des parias que Léon (le Disparu), narrateur second, épousera en même temps que Suryavati. Un autre aspect de l’intertexte se rattache aux deux figures de Rimbaud, le jeune voyou de Paris et l’homme malade d’Aden. Le renvoi implicite à la formule « Je est un autre » accentue les complexités de l’énonciation et les glissements de l’identité. Les très nombreuses citations de poèmes soulignent la tendance poétique plus que narrative de l’écriture de Le Clézio. Tandis que les citations du « journal d’un botaniste » révèlent la nostalgie d’un discours descriptif savant et neutre. Ainsi, le vertige intertextuel manifeste et multiplie les contradictions dynamiques qui animent l’écriture de Le Clézio et contribuent à la production du sens

Duras : Les voix du silence

« Duras, les voix du silence ». Formule d'emprunt, déviée, déplacée, pour servir de titre. Mais faut-il le prendre « pour argent comptant » ce paradoxe à la Duras, détour par « une voix comme greffée, la voix d'un autre... » ? Marguerite Duras le dit en d'autres mots dans Écrire (1993) : « Écrire c'est aussi ne pas parler. C'est se taire. C'est hurler sans bruit » (É34). Et pourtant, derrière cette écriture « du silence », quel bruissement de voix ! Au cinéma, d'abord. Car les « voix » duras-..

Development patterns of an isolated oligo-mesophotic carbonate buildup, early Miocene, Yadana field, offshore Myanmar

The development history of an oligo-mesophotic, early Miocene, isolated carbonate system (>160 m in thickness), forming the uppermost part of the Oligo-Miocene Yadana buildup (northern Andaman Sea), has been evidenced from the integration of sedimentological core studies from 4 wells (cumulated core length: 343 m), well correlations, seismic interpretation and analysis of the ecological requirements of the main skeletal components. Three types of carbonate factory operated on the top of the platform, depending on water-depth, turbidity and nutrient level: (1) a scleractinian factory developing under mesophotic conditions during periods of high particulate organic matter supplies, (2) an echinodermal factory occupying dysphotic to aphotic area of the platform coevally with the scleractinian factory, (3) a large benthic foraminiferal-coralline algal factories prevailing under oligo-mesophotic and oligo-mesotrophic conditions. The limited lateral changes in facies between wells, together with the seismic expression of the Yadana buildup, suggest deposition on a flat-topped shelf. Carbonate production and accumulation on the Yadana platform was mainly controlled by light penetration, nutrient content and hydrodynamic conditions. Scleractinian-rich facies resulted from transport of coral pieces derived from mesophotic environments (mounds?) and deposited in deeper, low light, mud-rich environments in which lived abundant communities of suspension feeders such as ophiuroids. Changes in monsoonal intensity, terrestrial runoff from the Irrawaddy River, upwelling currents and internal waves activity during the early Miocene are likely responsible for significant variations in water turbidity and nutrient concentration in the Andaman Sea, thus promoting the development of an oligo-mesophotic, incipiently drowned platform

Laboratory NMR Study to Quantify the Water Saturation of Partially Saturated Porous Rocks

The low-field nuclear magnetic resonance (NMR) technique is widely used as a noninvasive method to characterize the water content of subsurface porous media, such as aquifers and hydrocarbon reservoirs, but the quantitative correlation between the water saturation and the NMR relaxation signal has not been fully addressed. We conducted a laboratory study to measure the NMR signals of sandstone samples with different water saturations and to develop an empirical model for estimating the water saturation. The partially saturatinthe irreducible water saturationg states were derived by a high-speed centrifuge. The result shows that the water saturation is proportional to the geometric mean of the transverse relaxation time and can be fitted through a power function. Moreover, it has been found that the fitting parameters vary with the porosity and exhibit similar behaviors with the parameters of the classical Archie equation. The water saturation as well as its mobility state can be estimated with the NMR signals and porosity data. The proposed method has the potential to be applied to detect and quantify the water content in vadose zones, phreatic aquifers, permafrost regions, and gas hydrate reservoirs

Full Scale of Pore-Throat Size Distribution and Its Control on Petrophysical Properties of the Shanxi Formation Tight Sandstone Reservoir in the North Ordos Basin, China

Pore-throat size distribution is a key factor controlling the storage capacity and percolation potential of the tight sandstone reservoirs. However, the complexity and strong heterogeneity make it difficult to investigate the pore structure of tight sandstone reservoirs by using conventional methods. In this study, integrated methods of casting thin section, scanning electron microscopy, high-pressure mercury intrusion (HPMI), and constant-pressure mercury intrusion (CPMI) were conducted to study the pore-throat size distribution and its effect on petrophysical properties of the Shanxi Formation tight sandstones in the northern Ordos Basin (China). Results show that pore types of the Shanxi tight sandstone reservoirs include intergranular pores, dissolution pores, intercrystalline micropores, and microfracture, while the throats are dominated by sheet-like and tube-shaped throats. The HPMI-derived pore-throat size ranges from 0.006 to 10 μm, and the pore-throats with a radius larger than 10 μm were less frequent. The pore body size obtained from CPMI shows similar characteristics with radii ranging from 100 to 525 μm, while the throat size varies greatly with radii ranging from 0.5 to 11.5 µm, resulting in a wide range of pore-throat radius ratio. The full range of pore size distribution curves obtained from the combination of HPMI and CPMI displays multimodal with radii ranging from 0.006 to 525 µm. Permeability of the tight sandstone reservoirs is primarily controlled by relatively larger pore throats with small proportions, and the permeability decreases as the proportions of smaller pore-throats increase. The pervading nanopores in the tight gas sandstone reservoirs contribute little to the permeability but play an important role in the reservoir storage capacity. A new empirical equation obtained by multiple regression indicates that r 15 (pore-throat size corresponding to 15% mercury saturation) is the best permeability estimator for tight gas sandstone reservoirs, which yields the highest correlation coefficient of 0.9629 with permeability and porosity

The Jurassic–Cretaceous depositional and tectonic evolution of the southernwestern margin of the Neotethys Ocean, Northern Oman and United Arab Emirates

The concept that the autochthonous, parautochthonous and allochthonous Permian–Cretaceous sequences in the United Arab Emirates (UAE) and Oman record the transition from platform, slope to basin sedimentation within the southern part of Neotethys has been fundamental to the interpretation of the geological history of the region. The results of a major geological mapping programme of the UAE, carried out by the British Geological Survey for the Federal Government of the UAE, coupled with the detailed examination of key sections within northern Oman has led to a re-evaluation of the geological evolution of this region. This detailed study has led to a greater appreciation of the sedimentology and depositional setting of the sediments laid down along the northeastern Arabian continental margin during the Jurassic to Cretaceous, allowing a more refined model of Neotethys Ocean basin evolution to be established. The model charts the progressive breakup of the Arabian continental margin and closure of Neotethys during the mid to late Cretaceous and is divided into three main stages: Stage 1—Initial rifting and formation of the Neotethys Ocean, followed by a prolonged period of stable, passive margin sedimentation which extended from the Permian to Late Jurassic times; Stage 2—Uplift and erosion of the shelf margin during the Late Jurassic to Early Cretaceous, coincident with increased carbonate-clastic sedimentation in the outer ramp, distal slope and basinal areas; Stage 3—Increased instability during the Late Cretaceous leading to the breakup of the platform margin and foreland basin sedimentation accompanying the obduction of the Oman-UAE ophiolite. Data obtained for the upper part of the platform and platform margin to slope successions has revealed that the topography of the “shelf”-slope-basinal margin was more subdued than previously thought, with this more gentle ramp margin morphology persisting until early to mid-Cretaceous times when the platform margin started to become unstable during ophiolite obduction. The thrust-repeated allochthonous sedimentary rocks of the Hamrat Duru Group were deposited on the outer platform margin/lower slope rise to basinal plain of this basin margin and includes the dismembered remains of two turbidite fan systems which fed carbonate-rich detritus into deeper parts of the ocean. A re-evaluation of the chert-rich sequences, previously equated with deposition on the abyssal plain of Neotethys, has led to the conclusion that they may record sedimentation at a much shallower level within a starved ocean basin, possibly in a mid-ramp (above storm wave base) to outer ramp setting. A marked change in basin dynamics occurred during the mid-Cretaceous leading to the development of a shallow ramp basin margin in Oman with terrestrial to shallow marine sedimentary rocks interdigitating with red siliceous mudstones. By contrast, the contemporaneous succession in the Dibba Zone of the UAE indicates considerable instability on a steep shelf break. This instability is recorded by the presence of several major olistostrome deposits within the Aruma Group of the UAE which are thought to have been generated in advance of the rapidly obducting Oman-UAE ophiolite

Patent Foramen Ovale Closure or Anticoagulation vs. Antiplatelets after Stroke

BACKGROUND Trials of patent foramen ovale (PFO) closure to prevent recurrent stroke have been inconclusive. We investigated whether patients with cryptogenic stroke and echocardiographic features representing risk of stroke would benefit from PFO closure or anticoagulation, as compared with antiplatelet therapy. METHODS In a multicenter, randomized, open-label trial, we assigned, in a 1:1:1 ratio, patients 16 to 60 years of age who had had a recent stroke attributed to PFO, with an associated atrial septal aneurysm or large interatrial shunt, to transcatheter PFO closure plus long-term antiplatelet therapy (PFO closure group), antiplatelet therapy alone (antiplatelet-only group), or oral anticoagulation (anticoagulation group) (randomization group 1). Patients with contraindications to anticoagulants or to PFO closure were randomly assigned to the alternative noncontraindicated treatment or to antiplatelet therapy (randomization groups 2 and 3). The primary outcome was occurrence of stroke. The comparison of PFO closure plus antiplatelet therapy with antiplatelet therapy alone was performed with combined data from randomization groups 1 and 2, and the comparison of oral anticoagulation with antiplatelet therapy alone was performed with combined data from randomization groups 1 and 3. RESULTS A total of 663 patients underwent randomization and were followed for a mean (+/- SD) of 5.3 +/- 2.0 years. In the analysis of randomization groups 1 and 2, no stroke occurred among the 238 patients in the PFO closure group, whereas stroke occurred in 14 of the 235 patients in the antiplatelet-only group (hazard ratio, 0.03; 95% confidence interval, 0 to 0.26; P<0.001). Procedural complications from PFO closure occurred in 14 patients (5.9%). The rate of atrial fibrillation was higher in the PFO closure group than in the antiplatelet-only group (4.6% vs. 0.9%, P = 0.02). The number of serious adverse events did not differ significantly between the treatment groups (P = 0.56). In the analysis of randomization groups 1 and 3, stroke occurred in 3 of 187 patients assigned to oral anticoagulants and in 7 of 174 patients assigned to antiplatelet therapy alone. CONCLUSIONS Among patients who had had a recent cryptogenic stroke attributed to PFO with an associated atrial septal aneurysm or large interatrial shunt, the rate of stroke recurrence was lower among those assigned to PFO closure combined with antiplatelet therapy than among those assigned to antiplatelet therapy alone. PFO closure was associated with an increased risk of atrial fibrillation

High resolution seismic stratigraphic analysis: An integrated approach to the subsurface geology of the SE Persian Gulf

Papers included in this dissertation: Paper 1: Farzadi, P. 2006a. The development of Middle Cretaceous carbonate platforms, Persian Gulf, Iran: Constraints from seismic stratigraphy, well and biostratigraphy. Petroleum Geoscience, 12, 59-68. Paper 2: Farzadi, P. 2006b. Seismic facies analysis based on 3D multi-attribute volume classification, Dariyan Formation, SE Persian Gulf. Journal of Petroleum Geology,29/2, 159-174. Paper 3: Farzadi, P. & Hesthammer, J. (Submitted 2006). Diagnosis of the Upper Cretaceous paleokarst and turbidite systems from the Iranian Persian Gulf using volume-based multiple seismic attribute analysis and pattern recognition. N.B.: Originally accepted for publication in the AAPG Bulletin, later rejected because the US government prohibits the publication of papers using Iranian government datasets. The manuscript has been re-submitted to Petroleum Geoscience. Paper 4: Farzadi, P. & Alaei, B. (Submitted 2006). Stratigraphic architecture of the Zagros Basin: towards an objective comparison of the Fold-Thrust Belt and Foreland provinces. Submitted to the Journal of Petroleum Geology; under consideration for a thematic issue. Presentation (at international meeting and on web): Farzadi, P. 2005. Stratal geometries of the Cretaceous carbonate systems: application of multiple volumes attributes analysis to 3-D seismic data from the Persian Gulf. At: Middle to Far East Carbonate Reservoirs: Exploration, Development and Exploitation. PESGB Carbonate conference, 15th & 16th Nov. 2005 London