34 research outputs found

    Neogene uplift of the Tian Shan Mountains observed in the magnetic record of the Jingou River section (northwest China)

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    The Tian Shan Mountains constitute central Asia's longest and highest mountain range. Understanding their Cenozoic uplift history thus bears on mountain building processes in general, and on how deformation has occurred under the influence of the India-Asia collision in particular. In order to help decipher the uplift history of the Tian Shan, we collected 970 samples for magnetostratigraphic analysis along a 4571-m-thick section at the Jingou River (Xinjiang Province, China). Stepwise alternating field and thermal demagnetization isolate a linear magnetization component that is interpreted as primary. From this component, a magnetostratigraphic column composed of 67 polarity chrons are correlated with the reference geomagnetic polarity timescale between ∼1 Ma and ∼23.6 Ma, with some uncertainty below ∼21 Ma. This correlation places precise temporal control on the Neogene stratigraphy of the southern Junggar Basin and provides evidence for two significant stepwise increases in sediment accumulation rate at ∼16–15 Ma and ∼11–10 Ma. Rock magnetic parameters also undergo important changes at ∼16–15 Ma and ∼11–10 Ma that correlate with changes in sedimentary depositional environments. Together with previous work, we conclude that growth history of the modern Tian Shan Mountains includes two pulses of uplift and erosion at ∼16–15 Ma and ∼11–10 Ma. Middle to upper Tertiary rocks around the Tian Shan record very young (<∼5 Ma) counterclockwise paleomagnetic rotations, on the order of 15° to 20°, which are interpreted as because of strain partitioning with a component of sinistral shear that localized rotations in the piedmont

    Modélisation du chauffage de flan circulaire dans un dispositif d'expansion biaxiale à haute température

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    Ce travail porte sur l'intégration d'un moyen de chauffage par conduction électrique (effet Joule) de flan circulaire au sein d'un dispositif d'expansion biaxiale. Ce dispositif permettra la caractérisation thermomécanique de l'Usibor®1500dans un trajet de déformation équibiaxiale à très haute température (jusqu'à 1°C). Dans un premier temps, on s'intéresse au chauffage de flan rectangulaire avec une confrontation entre expérience et simulation, qui a permis de valider le modèle thermoélectrique réalisé sous COMSOL Multiphysics®. Dans un second temps, on aborde l'optimisation du champ électrique afin d'obtenir un chauffage rapide et homogène d'un flan circulaire.This work focuses on the integration of an electrical conduction heating of circular blank in a bulge-test device. This device will allow the thermomechanical characterization of Usibor®1500under biaxial deformation at very high temperature (to 1°C). First a thermoelectric model using COMSOL Multiphysics® was developed to study the heating of a rectangular blank. This model is validated by comparing the calculated temperatures with thermocouple measurements. Secondly electrical field optimization is approached to obtain a fast and uniform heating of a circular blank

    L'indemnisation des terrains agricoles en matière d'expropriation [Analyse de la jurisprudence des Cours d'appel de Rennes et d'Angers ]

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    Graveleau Philippe. L'indemnisation des terrains agricoles en matière d'expropriation [Analyse de la jurisprudence des Cours d'appel de Rennes et d'Angers ]. In: Revue Judiciaire de l'Ouest, 1981-1. pp. 1-28

    Sommaires de jurisprudence

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    Graveleau Philippe. Sommaires de jurisprudence. In: Revue juridique de l'Ouest, 1988-1. pp. 119-121

    Sommaires de jurisprudence en droit administratif

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    Graveleau Philippe. Sommaires de jurisprudence en droit administratif. In: Revue juridique de l'Ouest, 1990-3. pp. 467-473

    Sommaires de jurisprudence en droit administratif

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    Graveleau Philippe. Sommaires de jurisprudence en droit administratif. In: Revue juridique de l'Ouest, 1992-1. pp. 95-104

    Sommaires de jurisprudence en droit administratif

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    Graveleau Philippe. Sommaires de jurisprudence en droit administratif. In: Revue juridique de l'Ouest, 1990-1. pp. 97-107

    Sommaires de jurisprudence en droit administratif

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    Graveleau Philippe. Sommaires de jurisprudence en droit administratif. In: Revue juridique de l'Ouest, 1990-1. pp. 97-107

    Sommaires de jurisprudence

    No full text
    Graveleau Philippe. Sommaires de jurisprudence. In: Revue juridique de l'Ouest, 1988-1. pp. 119-121
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