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Thebault E, Chulliat A, Maus S, Hulot G, LANGLAIS Benoit, Chambodut A, Menvielle M,. (2010). IGRF candidate models at times of rapid changes in core field acceleration. Earth Planet and Space, 62, 753–763.
Abstract: We submit three candidate models following the call for IGRF-11. We apply a simple modeling approach in spherical harmonics based on a quadratic Taylor expansion for the internal field time variations. We use the Dst magnetic index as a proxy for the external field variations. In order to compensate for the limitations incurred by such a conventional approach, we focus on the optimal selection of satellite data in space and time. We also show that some a priori knowledge about the core field state helps us to avoid the pitfall encountered in the case of rapid changes of core field accelerations. Indeed, various acceleration events of relevance for the IGRF 11th occurred between 2003 and 2010, one of them being a geomagnetic jerk. They could entail disagreements between IGRF candidate models for the secular variation (SV) if data prior to 2008 are used. Our SV and main field (MF) candidate models have a root mean square uncertainty less than 6 nT/yr and 8nT, respectively, with respect to the modeled magnetic field contributions. These values correspond to the intrinsic error associated with truncating SV and MF models to spherical harmonic degree 8 and 13, respectively, as requested for IGRF models.
Programme: 139
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Cherel Y., Charrassin J.B. & Handrich Y. (1993). Comparison of Body Reserve Buildup in Prefasting Chicks and Adults of King penguins(Aptenodytes patagonicus). Physiological zoology, 66(5), 750–770.
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Geoffroy, L.; Aubourg, C.; Callot, J.-P.; Barrat, J.-A. (2007). Mechanisms of crustal growth in large igneous provinces: The north Atlantic province as a case study. Geological Society of America Special Papers, 430, 747–774.
Abstract: The mechanisms of magma crust accretion at large igneous provinces (LIPs) are questioned using arguments based on the north Atlantic case. Published and new data on the calculated flow vectors within dike swarms feeding the early traps and subsequent seaward-dipping reflector lavas suggest that most of the mafic magmas forming the north Atlantic LIP transited through a small number of igneous centers. The magma was injected centrifugally in dike swarms at some distance away from individual igneous centers along the trend of the maximum horizontal stress acting in the crust, feeding lava piles via dikes intersecting the ground surface. This mechanism is similar to that observed in present-day Iceland and, more generally, in mafic volcano-tectonic systems. The absence of generalized vertical magma transit in a LIP has major geodynamic consequences. We cannot link the surface extent of LIP magmas to the dimensions of the mantle melting zone as proposed in former plume head models. The distribution of LIP magmas at the surface is primarily controlled by the regional stress field acting within the upper crust, but is also affected by magma viscosity. The igneous centers feeding LIPs most likely represent the crustal expression of small-scale convective cells of the buoyant mantle naturally located beneath the mechanical lithosphere.
Keywords: traps; volcanic margin; dike swarm; small-scale convection; AMS
Programme: 290
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Krinner G. & Genthon C. (1998). GCM simulations of the Last Glacial Maximum surface climate of Greenland and Antarctica. Climate dynamics, 14(9), 741–758.
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Laurin B., Feral J.P., David B. & Derelle E. (1994). Phylogeny of the spatangoid echinoid Echinocardium: morphological versus molecular approach. Echinoderms through time, , 739–745.
Abstract: Echinoderms through time, Proc. 8th I.EC, Dijon
Programme: 195
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Rosnet E., Cazes G. & Bachelard C. (1998). Méthodes de sélection et de contrôle de l'adaptation dans une situation extrême: le cas des hivernages polaires. Bulletin de psychologie, 51(6), 737–763.
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Giret A., Gregoire M., Cottin J.Y. & Michon G. (1997). Kerguelen, a Third Type of Oceanic Islands. Recent progress in Antarctic Earth Sciences, , 735–741.
Abstract: Recent progress in Antarctic Earth Sciences, Terra Antarctica publi, Siena
Programme: 251
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Weimerskirch, H., Pinaud, D, Pawlowski, F. & Bost, CA. (2007). Does Prey Capture Induce Area-Restricted Search? A Fine-Scale Study Using GPS in a Marine Predator,the Wandering Albatross capture and GPS. Am. Nat., 170(5), 735–743.
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Van Den Broeke M.R. & Van Lipzig N P.M. (2003). Factors controlling the near-surface wind field in Antarctica. Monthly weather review, 131, 733–743.
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Berteaux D. (1993). Female-biased mortality in a sexually dimorphic ungulate:feral cattle of amsterdam Island. J. Mammal., 74(3), 732–737.
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