Éditeur(s) : HAL CCSD American Medical Association (AMA)
Résumé : International audience
IMPORTANCE Although frequently used in treating intensive care unit (ICU) patients with sepsis, empirical antifungal therapy, initiated for suspected fungal infection, has not been shown to improve outcome. OBJECTIVE To determine whether empirical micafungin reduces invasive fungal infection (IFI)-free survival at day 28. DESIGN, SETTING, AND PARTICIPANTS Multicenter double-blind placebo-controlled study of 260 nonneutropenic, nontransplanted, critically ill patients with ICU-acquired sepsis, multiple Candida colonization, multiple organ failure, exposed to broad-spectrum antibacterial agents, and enrolled between July 2012 and February 2015 in 19 French ICUs. INTERVENTIONS Empirical treatment with micafungin (100mg, once daily, for 14 days) (n = 131) vs placebo (n = 129). MAIN OUTCOMES AND MEASURES The primary end pointwas survival without proven IFI 28 days after randomization. Key secondary end points included new proven fungal infections, survival at day 28 and day 90, organ failure, serum (1-3)-beta-D-glucan level evolution, and incidence of ventilator-associated bacterial pneumonia. RESULTS Among 260 patients (mean age 63 years; 91 [35%] women), 251 (128, micafungin group; 123, placebo group) were included in the modified intent-to-treat analysis. Median values were 8 for Sequential Organ Failure Assessment (SOFA) score, 3 for number of Candida-colonized sites, and 99 pg/mL for level of (1-3)-beta-D-glucan. On day 28, there were 82 (68%) patients in the micafungin group vs 79 (60.2%) in the placebo group who were alive and IFI free (hazard ratio [HR], 1.35 [95% CI, 0.87-2.08]). Results were similar among patients with a (1-3)-beta-D-glucan level of greater than 80 pg/mL (n = 175; HR, 1.41 [95% CI, 0.85-2.33]). Day-28 IFI-free survival in patients with a high SOFA score (> 8) was not significantly different when compared between the micafungin vs placebo groups (HR, 1.69 [95% CI, 0.96-2.94]). Use of empirical micafungin decreased the rate of new invasive fungal infection in 4 of 128 patients (3%) in the micafungin group vs placebo (15/123 patients [12%]) (P =.008). CONCLUSIONS AND RELEVANCE Among nonneutropenic critically ill patients with ICU-acquired sepsis, Candida species colonization at multiple sites, and multiple organ failure, empirical treatment with micafungin, compared with placebo, did not increase fungal infection-free survival at day 28.
ISSN: 0098-7484

hal-01405822
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01405822
DOI : 10.1001/jama.2016.14655
PUBMED : 27706483

Éditeur(s) : HAL CCSD Elsevier
Résumé :  
absent
Ecology and management of a neotropical rainforest: lessons drawn from Paracou, a long-term experimental research site in French Guiana

ISBN : 2-84299-455-8
hal-01189214
https://hal.archives-ouvertes.fr/hal-01189214
PRODINRA : 16123

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Plio-Pleistocene diatomitic sequences in the Shamb paleo-lake (South Armenia, Lesser Caucasus) offer a rare opportunity to give new insights on the paleo-climate of Western Asia. We present an integrated palynological, 40Ar/39Ar geochronologic and magnetostratigraphic study for the most complete section in the sedimentary deposits of the Shamb paleo-lake. 40Ar/39Ar dating of two volcaniclastic layers provided ages of 1.24 ± 0.03 and 1.16 ± 0.02 Ma (2. Magnetostratigraphic data show that the entire Shamb section is of reversed polarity which, combined with 40Ar/39Ar dating, suggests that the entire section correlates with part of the Matuyama period (1.785-1.070 Ma). Pollen assemblages and macroremains diversity clearly show an alternation of glacial and interglacial phases. Age calibrations and accumulation rate extrapolation allow a direct correlation of climate changes with the global isotopic curve, and show that the Shamb section probably ranges from approximately 1.300 to 1.080 Ma (marine isotopic stages 40 to 31). The vegetation of the Lesser Caucasus developed in a mosaic pattern in a Pleistocene continental, mostly arid climate, comparable to the present-day climate. The observed vegetation changes record a dominant climate response to the obliquity orbital parameter, but the influence of precession could not be established from the Shamb data. Pollen and macroflora both indicate that glacial periods were cold and dry and that interglacials were warm with local humidity. The early Pleistocene climatic model for Western Asia is thus similar to the climatic model for the Mediterranean area.
ISSN: 0012-821X

hal-00470353
https://hal.archives-ouvertes.fr/hal-00470353
DOI : 10.1016/j.epsl.2010.01.007

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0168-583X

hal-01685822
https://hal.univ-antilles.fr/hal-01685822
DOI : 10.1016/0168-583X(90)90675-K

Éditeur(s) : HAL CCSD Oxford University Press (OUP): Policy B - Oxford Open Option A Oxford University Press (OUP)
Résumé : International audience
Peridotites exhumed in the footwall of axial detachment faults at slow-spreading ridges are highly serpentinized. Most mid-ocean ridge detachment settings are magmatically active and hydrous fluid circulation in and near the fault has been shown to be influenced by the presence of melt or magmatic lithologies. Our working area along the Southwest Indian Ridge (62–65°E) is nearly amagmatic and represents an end-member to study the hydrous alteration of exhumed peridotites without these magmatic influences. We use an integrated petrological approach combining microstructural, mineralogical and chemical observations to unravel the sequence of serpentinization in 272 dredged samples of variably serpentinized peridotites and to document the circulation of serpentinizing fluids in and near the exhumation faults. We find that serpentine recrystallization and veins overprint the initial serpentinite mesh texture in ∼25% of the samples. Oxygen isotope data suggest that this sequence developed at relatively high temperatures (271–336°C) and under increasing fluid–rock ratios, from near stoichiometry for mesh texture formation to >10 during recrystallization. Increasing fluid supersaturation relative to serpentine favors the replacement of mesh texture lizardite by chrysotile and polygonal or polyhedral serpentine. We attribute local recrystallization into antigorite to moderate Si-metasomatism, possibly following pyroxene serpentinization. We do not observe the more pronounced Si-metasomatism leading to talc replacing serpentine that is reported for the more magmatically active Mid-Atlantic Ridge detachment settings and is attributed to prior leaching of magmatic rocks. Scales of preferential fluid pathways in our samples evolved from pervasive and close-spaced (<500 µm) microfractures during the formation of the initial serpentine mesh texture, to centimeter-thick planar domains of enhanced fluid flux, spaced at ∼10 cm intervals and probably grouped in corridors that may be up to ∼100 m across. Serpentine minerals are enriched in some fluid-mobile elements (Cl, B, U) relative to the peridotite protolith, and several elements (Al, Fe, Si, Cu, As, Sb, REE) are redistributed at the millimeter to decimeter scale. Serpentinizing fluids were seawater-derived, probably mildly alkaline (small to no europium anomalies), reducing and H2-enriched (formation of magnetite). These fluids may have been similar to, though warmer than, those venting at the ultramafic-hosted Lost City hydrothermal fluid (30°N, Mid-Atlantic Ridge).
ISSN: 0022-3530

hal-01174047
https://hal.archives-ouvertes.fr/hal-01174047
DOI : 10.1093/petrology/egv014

Éditeur(s) : HAL CCSD
Résumé : International audience
1er Colloque de l’Association pour la Recherche sur l’Intervention en Sport, Université de Grenoble
Grenoble, France

hal-01613697
https://hal.univ-antilles.fr/hal-01613697

Éditeur(s) : HAL CCSD springer Link
Résumé : International audience
Experimental Astronomy

hal-01094521
https://hal.archives-ouvertes.fr/hal-01094521
BIBCODE : 2014ExA...tmp...41R
DOI : 10.1007/s10686-014-9383-4
ARXIV : 1310.0696

Éditeur(s) : HAL CCSD Wiley
Résumé : Diversified deep-water corals and associated communities occur in early Pleistocene (early Calabrian; ∼1.7–1.6 Ma) calcareous crusts discovered on the south-western coast of Karpathos Island (eastern Greece). Apart from abundant and conspicuous solitary and colonial corals (12 species), the accompanying fauna comprises mostly bivalves (10 species), serpulid worms (4 species), and bryozoans (40 species). The growth and deposition of the studied organisms occurred in an upper bathyal environment at water depths around 400–600 m. The calculated mean uplift rate after deposition of the crusts indicates that Karpathos was drowned during the earliest Calabrian and experienced severe uplifts by the late Calabrian. A comparison between these communities and those of the Pleistocene to Recent Mediterranean and north-east Atlantic shows that a common stock of taxa exist(ed); among them two azooxanthellate colonial scleractinians (Lophelia pertusa and Madrepora oculata) are predominant.
ISSN: 0267-8179

hal-01622744
https://hal.archives-ouvertes.fr/hal-01622744
DOI : 10.1002/jqs.2966

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
The etiology of congenital heart defect (CHD) combines environmental and genetic factors. So far, there were studies reporting on the screening of a single gene on unselected CHD or on familial cases selected for specific CHD types. Our goal was to systematically screen a proband of familial cases of CHD on a set of genetic tests to evaluate the prevalence of disease-causing variant identification. A systematic screening of GATA4, NKX2-5, ZIC3 and Multiplex ligation-dependent probe amplification (MLPA) P311 Kit was setup on the proband of 154 families with at least two cases of non-syndromic CHD. Additionally, ELN screening was performed on families with supravalvular arterial stenosis. Twenty-two variants were found, but segregation analysis confirmed unambiguously the causality of 16 variants: GATA4 (1 x), NKX2-5 (6 x), ZIC3 (3 x), MLPA (2 x) and ELN (4 x). Therefore, this approach was able to identify the causal variant in 10.4% of familial CHD cases. This study demonstrated the existence of a de novo variant even in familial CHD cases and the impact of CHD variants on adult cardiac condition even in the absence of CHD. This study showed that the systematic screening of genetic factors is useful in familial CHD cases with up to 10.4% elucidated cases. When successful, it drastically improved genetic counseling by discovering unaffected variant carriers who are at risk of transmitting their variant and are also exposed to develop cardiac complications during adulthood thus prompting long-term cardiac follow-up. This study provides an important baseline at dawning of the next-generation sequencing era.
ISSN: 1018-4813

hal-01404211
https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01404211
DOI : 10.1038/ejhg.2015.105
PUBMED : 26014430

Éditeur(s) : HAL CCSD BMJ Publishing Group
Résumé : For the ICARE Study Group
International audience
Objective Our objective was to investigate the association between head and neck cancer and occupational exposure to chlorinated, oxygenated and petroleum solvents in women.Methods Investigation of occupational and environmental CAuses of REspiratory cancers (ICARE), a French population-based case–control study, included 296 squamous cell carcinomas of the head and neck (HNSCC) in women and 775 female controls. Lifelong occupational history was collected. Job-exposure matrices allowed to assess exposure to 5 chlorinated solvents (carbon tetrachloride; chloroform; methylene chloride; perchloroethylene; trichloroethylene), 5 petroleum solvents (benzene; special petroleum product; gasoline; white spirits and other light aromatic mixtures; diesel, fuels and kerosene) and 5 oxygenated solvents (alcohols; ketones and esters; ethylene glycol; diethyl ether; tetrahydrofuran). OR and 95% CIs, adjusted for smoking, alcohol drinking, age and geographical area, were estimated with logistic models.Results Elevated ORs were observed among women ever exposed to perchloroethylene (OR=2.97, 95% CI 1.05 to 8.45) and trichloroethylene (OR=2.15, 95% CI 1.21 to 3.81). These ORs increased with exposure duration (OR=3.75, 95% CI 0.64 to 21.9 and OR=4.44, 95% CI 1.56 to 12.6 for 10 years or more, respectively). No significantly increased risk of HNSCC was found for occupational exposure to the other chlorinated, petroleum or oxygenated solvents.Conclusions These findings suggest that exposure to perchloroethylene or trichloroethylene may increase the risk of HNSCC in women. In our study, there is no clear evidence that the other studied solvents are risk factors for HNSCC.
ISSN: 2044-6055

Droits : http://creativecommons.org/licenses/by-nc/
hal-01438872
http://hal.upmc.fr/hal-01438872
http://hal.upmc.fr/hal-01438872/document
http://hal.upmc.fr/hal-01438872/file/e012833.full.pdf
DOI : 10.1136/bmjopen-2016-012833

Éditeur(s) : HAL CCSD Elsevier Elsevier Masson
Résumé : New field and micropalaeontological investigations have been conducted in four of the Pliocene rias of the internal zone of the Rif in Morocco, on the southern margin of the Alboran Sea. We found that marine sediments outcropping in these rias were deposited mainly during the Early Zanclean, between 5.04 and 3.8 Ma. After a transgressive episode that led to the deposition of terrestrial to marine conglomerates, dark clays deposited first at shallow palaeo-depths and then at bathyal palaeo-depths. The rias were then infilled with a shallowing upward succession comprising marine clays and sandstone and, locally, terrestrial sediments that indicate their final emersion. No Gilbert-deltas were observed in these rias. The presence of transgressive deposits at the bottom of the rias, also identified in other basins of the external zone of the Rif, and the absence of Gilbert deltas question a catastrophic reflooding after the Messinian Salinity Crisis in this area.
ISSN: 1631-0713

hal-01115243
https://hal.archives-ouvertes.fr/hal-01115243
DOI : 10.1016/j.crte.2014.03.002

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Properly assessing the extent and magnitude of fault ruptures associated with large earthquakes is critical for understanding fault behavior and associated hazard. Submarine faults can trigger tsunamis, whose characteristics are defined by the geometry of seafloor displacement, studied primarily through indirect observations (e.g., seismic event parameters, seismic profiles, shipboard bathymetry, coring) rather than direct ones. Using deep-sea vehicles, we identify for the first time a marker of coseismic slip on a submarine fault plane along the Roseau Fault (Lesser Antilles), and measure its vertical displacement of ∼0.9 m in situ. We also map recent fissuring and faulting of sediments on the hangingwall, along ∼3 km of rupture in close proximity to the fault's base, and document the reactivation of erosion and sedimentation within and downslope of the scarp. These deformation structures were caused by the 2004 M w 6.3 Les Saintes earthquake, which triggered a subsequent tsunami. Their characterization informs estimates of earthquake recurrence on this fault and provides new constraints on the geometry of fault rupture, which is both shorter and displays locally larger coseismic displacements than available model predictions that lack field constraints. This methodology of detailed field observations coupled with near-bottom geophysical surveying can be readily applied to numerous submarine fault systems, and should prove useful in evaluating seismic and tsunamigenic hazard in all geodynamic contexts.
ISSN: 0012-821X

insu-01557932
https://hal-insu.archives-ouvertes.fr/insu-01557932
https://hal-insu.archives-ouvertes.fr/insu-01557932/document
https://hal-insu.archives-ouvertes.fr/insu-01557932/file/EPSL-2006-escartin.pdf
DOI : 10.1016/j.epsl.2016.06.024

Éditeur(s) : HAL CCSD
Résumé : International audience
Journées internationalessur la communication, l'éducation et la culture scientifique et industrielle
Chamonix, France

hal-01620768
https://hal.univ-antilles.fr/hal-01620768
https://hal.univ-antilles.fr/hal-01620768/document
https://hal.univ-antilles.fr/hal-01620768/file/Atelier%20Forissier-ClementJIES2001.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
OBJECTIVES: We investigated the relationship between lung cancer and occupational exposure to welding activity in ICARE, a population-based case-control study. METHODS: Analyses were restricted to men (2276 cases, 2780 controls). Welding exposure was assessed through detailed questionnaires, including lifelong occupational history. ORs were computed using unconditional logistic regression, adjusted for lifelong cigarette smoking and occupational exposure to asbestos. RESULTS: Among the regular welders, welding was associated with a risk of lung cancer (OR=1.7, 95% CI 1.1 to 2.5), which increased with the duration (OR=2.0, 95% CI 1.0 to 3.9 when duration extgreater10 years), and was maximum 10-20 years since last welding. The risk was more pronounced in case of gas welding (OR=2.0, 95% CI 1.2 to 3.3), when the workpiece was covered by paint, grease, or other substances (OR=2.0, 95% CI 1.2 to 3.4) and when it was cleaned with chemical substances before welding. No statistically significant increase in lung cancer risk was observed among occasional welders. CONCLUSIONS: Although these results should be confirmed, we showed that type of welding and mode of workpiece preparation are important determinants of the lung cancer risk in regular welders
Occupational and Environmental Medicine

hal-01274887
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01274887
DOI : 10.1136/oemed-2015-102964
PUBMED : 26865654

Éditeur(s) : HAL CCSD AGU and the Geochemical Society
Résumé : International audience
Rainbow is a dome-shaped massif at the 36°14′N nontransform offset along the Mid-Atlantic Ridge. It hosts three ultramafic-hosted hydrothermal sites: Rainbow is active and high temperature; Clamstone and Ghost City are fossil and low temperature. The MoMARDREAM cruises (2007, 2008) presented here provided extensive rock sampling throughout the massif that constrains the geological setting of hydrothermal activity. The lithology is heterogeneous with abundant serpentinites surrounding gabbros, troctolites, chromitites, plagiogranites, and basalts. We propose that a W dipping detachment fault, now inactive, uplifted the massif and exhumed these deep-seated rocks. Present-day deformation is accommodated by SSW-NNE faults and fissures, consistent with oblique teleseismic focal mechanisms and stress rotation across the discontinuity. Faults localize fluid flow and control the location of fossil and active hydrothermal fields that appear to be ephemeral and lacking in spatiotemporal progression. Markers of high-temperature hydrothermal activity (∼350°C) are restricted to some samples from the active field while a more diffuse, lower temperature hydrothermal activity (<220°C) is inferred at various locations through anomalously high As, Sb, and Pb contents, attributed to element incorporation in serpentines or microscale-sulfide precipitation. Petrographic and geochemical analyses show that the dominant basement alteration is pervasive peridotite serpentinization at ∼160–260°C, attributed to fluids chemically similar to those venting at Rainbow, and controlled by concomitant alteration of mafic-ultramafic units at depth. Rainbow provides a model for fluid circulation, possibly applicable to hydrothermalism at oceanic detachments elsewhere, where both low-temperature serpentinization and magmatic-driven high-temperature outflow develop contemporaneously, channeled by faults in the footwall and not along the detachment fault.
ISSN: 1525-2027

hal-01115281
https://hal.archives-ouvertes.fr/hal-01115281
https://hal.archives-ouvertes.fr/hal-01115281/document
https://hal.archives-ouvertes.fr/hal-01115281/file/Andreani_et_al-2014-Geochemistry%2C_Geophysics%2C_Geosystems.pdf
DOI : 10.1002/2014GC005269

Éditeur(s) : HAL CCSD Société géologique de France
Résumé : International audience
In this paper we present and discuss new investigations performed on both the magmatic basement and the sedimentary formations of La Désirade. We report structural and sedimentary evidences for several episodes of deformation and displacement occurring prior to the present day tectonics. The main faults, respectively N130 ± 10°, N040 ± 10° and N090 ± 10°, previously considered as marker of the current tectonic regime corresponds to reactivated tectonic structures developed first during late Cretaceous compression and second during Pliocene to early Pleistocene extension. We demonstrate also the importance of late Pliocene-early Pleistocene and middle-late Pleistocene vertical movements in this part of the Lesser Antilles fore-arc as well as the role of compressive tectonics in the over thickened character of the arc basement in the Guadeloupe archipelago
EISSN: 1777-5817

hal-00830329
https://hal.archives-ouvertes.fr/hal-00830329
DOI : 10.2113/gssgfbull.184.1-2.21

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: The potential interest of antifungal treatment of non-immunocompromized patients with sepsis, extra-digestive Candida colonization and multiple organ failure is unknown. It represents three-quarters of antifungals prescribed in Intensive Care Units. It may allow early treatment of invasive fungal infection in the incubation phase but expose patients to unnecessary antifungal treatments with subsequent cost and fungal selection pressure. As early diagnostic tests for invasive candidiasis are still considered to be insufficient, the potential interest in this strategy needs to be demonstrated. METHODS: This prospective multicenter, double blind, randomized-controlled trial is conducted in 23 French Intensive Care Units. All adult patients, mechanically ventilated for more than four days with sepsis of unknown origin and with at least one extradigestive fungal colonization site and multiple organ failure are eligible for randomization. Patients with proven invasive candidiasis are not included. After a complete mycological screening, patients are allocated to receive micafungin 100 mg intravenously once a day or placebo for 14 days. We plan to enroll 260 patients. The main objective is to demonstrate that micafungin increases survival of patients without invasive candidiasis at day 28 as compared to placebo. Other outcomes include day 28 and 90 survival and organ failure evolution. Additionally, pharmacokinetics of micafungin in enrolled patients will be measured and evolution of fungal biomarkers and susceptibility profiles of infecting fungi will also be followed. DISCUSSION: This study will help to provide guidelines for treating non-immunocompromized patients with fungal colonization multiple organ failure and sepsis of unknown origin.Trial registration: Clinicaltrials.gov number NCT01773876.
ISSN: 1745-6215

inserm-00913515
http://www.hal.inserm.fr/inserm-00913515
http://www.hal.inserm.fr/inserm-00913515/document
http://www.hal.inserm.fr/inserm-00913515/file/1745-6215-14-399.pdf
PUBMED : 24261608

Éditeur(s) : HAL CCSD Elsevier
Résumé : Field isolates of Toxoplasma gondii in Europe and North America have been grouped into three clonal lineages that display different virulence in mice. Whether the genetic structure of the parasite is related to clinical expression in humans has not yet been demonstrated. We developed an enzyme-linked immunosorbent assay which uses lineage-specific, polymorphic polypeptides derived from the dense granule antigens, GRA5 and GRA6. Our goal was to compare serotypical patterns observed in asymptomatic versus symptomatic (ocular disease and severe infection in human immunodeficiency virus (HIV)-positive patients) infections among patients from Europe and South America. Independent of the clinical presentation of the disease, serotypes differed according to geographical origin, with a homogeneous distribution of serotype II in Europe and of serotypes I and III in South America. We conclude that GRA5-GRA6 serotyping is an interesting tool to study serotype prevalence in populations but it is not an accurate marker of pathogenicity of Toxoplasma infection in humans.
ISSN: 1286-4579

hal-00306841
https://hal.archives-ouvertes.fr/hal-00306841
DOI : 10.1016/j.micinf.2008.04.001
PUBMED : 18539501

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Located on the margin of the west Alboran basin, the Gibraltar Arc (Betic-Rif mountain belt) displays post-Pliocene vertical movements evidenced by uplifted marine sedimentary basins and marine terraces. Quantification of vertical movements is an important clue to understand the origin of present-day relief generation in the Betic-Rif mountain chain together with the causes of the Messinian Salinity Crisis. In this paper, we present the results of a pluridisciplinary study combining an analysis of low temperature thermochronology and Pliocene basins evolution to constrain the exhumation history and surface uplift of internals units of the Rif belt (Northern Morocco). The mean (U-Th)/He apatite ages obtained from 11 samples are comprised between 14.1 and 17.8 Ma and display a wide dispersion, which could be explained by a great variability of apatite chemistries in the analyzed samples. No correlations between altitude and age have been found along altitudinal profile suggesting a rapid exhumation during this period. Thermal modeling using our (U-Th)/He apatite ages and geochronological data previously obtained in the same area (40Ar/39Ar and K/Ar data on biotite, zircon and apatite fission track) allow us to propose a cooling history. The rocks suffered a rapid cooling at 60-100 °C/Ma between 22.5 and 19 Ma, then cooled to temperatures around 40 °C between 19 and 18 Ma. They were re-heated at around 110 °C between 18 and 15 Ma then rapidly cooled and exhumed to reach the surface temperature at around 13 Ma. The re-heating could be related to a renewal in thrusting and burying of the inner zones. Between 15 and 13 Ma the cooling resumed at a rate of 50 °C/Ma indicating an exhumation rate of 0.8 mm/y considering an average 40 °C/km geothermal gradient. This exhumation may be linked to the extension in the Alboran Sea. Otherwise biostratigraphic and sedimentological analysis of Pliocene basins of the internal Rif provided informations on the more recent events and vertical movements. Pliocene deposits of the Rifian coast represent the passive infilling of palaeo-rias between 5.33 and 3.8 Ma. The whole coastal area was uplifted at slow average rates (0.01-0.03 mm/y) in relation with a northeastward tilting of 0.2-0.3° since the Lower-Pliocene. A late Pliocene to present extensional tectonics associated to uplift has been identified all along the coastal ranges of the Internal Zone of the Rif chain. This extension was coeval with the major late Pliocene to Pleistocene extensional episode of the Alboran Sea and appears to be still active nowadays. No significant late Messinian uplift was evidenced, thus calling into question the geodynamic models relating the closure of the marine gateways and the MSC to slab roll back.
ISSN: 0264-3707

hal-01053531
https://hal.archives-ouvertes.fr/hal-01053531
DOI : 10.1016/j.jog.2014.01.006

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The Karukéra spur is an easternmost submerged rise of the Lesser Antilles fore-arc in the Guadeloupe archipelago, culminating about 4000 m above the fore-arc basin 150 km west of the deformation front. The analysis of 3500 km 2D high-resolution multichannel seismic reflection and multibeam bathymetric data, and the study of 14 core samples, allow for the first time to reconstruct its sedimentary anatomy and tectonic evolution. Seven seismic units (US1 to US7) are evidenced, organised into four major depositional sequences separated by erosional surfaces. Units US1 to US4 thicken to the south-southeast on the spur. The sedimentary deposits rest upon a deeply eroded metamorphic basement of the Caribbean Plate as in La Désirade Island. Sequence 1 (units US1 and US2) remains unknown in its lower part because it does not outcrop. Its upper part comprises early Miocene shallow water carbonates. Sequence S2 (Unit US3) only comprises an upper Miocene transgressive systems tract deposited into basinal environment. It is bounded by major erosional surfaces SB2 and SB3. Sequence 3 (US4 to US6) is Zanclean to Pleistocene. It is dominantly composed of shallow water, reefal deposits. Sequence 4 corresponds to recent deposits. The Karukéra spur experienced three main extensional episodes with alternations between uplift and subsidence periods. Uplifts are responsible for emersions and erosions. Subsidence severely drowned shallow water deposits. The first extensional episode led to the formation of horsts and grabens in the basement, prior to early Miocene deposits. The second extensional episode occurred during upper Miocene, in accordance with data in surrounding islands. The third tectonic episode developed since Calabrian. Noticeable is the constant reactivation of N130°–N150°, N150°–N180° and N40° trending faults since early Miocene and the neoformation of E–W trending faults since Calabrian. Our results suggest that at the latitude of Guadeloupean archipelago the Lesser Antilles subduction zone is an erosional margin because of the successive sweepings of the Santa Lucia then Tiburon Ridges.
ISSN: 0025-3227

hal-01172231
https://hal.archives-ouvertes.fr/hal-01172231
DOI : 10.1016/j.margeo.2015.02.007