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Gounelle M., Engrand C., Bland P.A., Zolensky M.E., Russell S.S. & Duprat J. (2003). D/H measurements of fossil micrometeorites: implications for the origin of water on Earth. (Vol. #11668).
Abstract: Introduction: Although still debated, the origin of water on Earth is usually ascribed to a late veneer of hydrous primitive bodies [1]. The isotopic composition of water hydrogen (D/H ratio) in a diversity of primitive extraterrestrial materials can help to assess the nature of the late veneer agent. We present measurements of D/H ratios of hydrated silicates in carbonaceous chondritic microclasts (CCMs) recently identified within achondrite meteorites [2]. These CCMs have been interpreted to be fossil micrometeorites [2]. Results: Measurements of D/H ratios in the matrix of 6 CM2-like and 6 CR2-like CCMs were performed by Secondary Ion Mass Spectrometry following the procedure described in [3]. D/H ratios from CM2-like carbonaceous chondritic microclasts matrix range from 117.6 × 10-6 to 171.0 × 10-6, with an average value of 132.7 × 10-6. D/H ratios from CR2-like carbonaceous chondritic microclasts matrix range from 112.8 × 10-6 to 203.8 × 10-6, with an average value of 169.4 × 10-6. D/H ratios in CM2-like microclasts compare well to bulk CM2 carbonaceous chondrites [4]. D/H ratios in CR2-like microclasts are significantly lower than D/H measured in bulk CR2 chondrites [4]. This discrepancy probably arises from the fact that bulk measurement techniques on meteorites take into account D-enriched organics in addition to water. The average value of all the microclasts’ population is D/H = 152.0 ± 4.8 × 10-6. Discussion: The CCMs D/H average value compares favourably to the terrestrial value (149 ± 3 × 10-6). This match suggests that fossil micrometeorites could have endowed Earth with water, provided that the micrometeorite flux on early Earth was large enough. This possibility will be discussed at the conference, in the light of flux data, and other constraints to be met such as the PGE abundance. References: [1] F. Robert, Science 293, 1056--1058 (2001). [2] M. Gounelle et al., Geochim. Cosmochim. Acta In press (2002). [3] C. Engrand et al., Meteoritics Planet. Sci. 34, 773--787 (1999). [4] J. F. Kerridge, Geochim. Cosmochim. Acta 49, 1707--1714 (1985).
Programme: 1065
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Gilles Alphonse Durand; Vincent Minier; Pierre-Olivier Lagage; Emanuele Daddi; Samir El Khouloudi; Nicola Schneider-Bontemps; Michel Talvard; Christian Veyssière; Gilles André Durand; Christian Walter; Lucia Sabbatini; Zalpha Challita; John W. (2008). Toward a large telescope facility for submm/FIR astronomy at Dome C (Vol. 7012).
Abstract: Submillimetre astronomy is the prime technique to unveil the birth and early evolution of stars and galaxies in the local and distant Universe. Preliminary meteorological studies and atmospheric transmission models tend to demonstrate that Dome C might offer atmosphere conditions that open the 200-µm atmospheric windows, and could potentially be a site for a large ground-based telescope facility. However, Antarctic climate conditions might also severely impact and deform any telescope mirror and hardware. We present prerequisite conditions and their associate experiments for defining a large telescope facility for submillimetre astronomy at Dome C: (1) Whether the submm/THz atmospheric windows open from 200 µm during a large and stable fraction of time; (2) The knowledge of thermal gradient and (3) icing formation and their impact on a telescope mirror and hardware. This paper will present preliminary results on current experiments that measure icing, thermal gradient and sky opacity at Dome C. We finally discuss a possible roadmap toward the deployment of a large telescope facility at Dome C.
Programme: 1040
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Lenoir X., Feraud G. & Geoffroy L. (2003). High-rate flexure of the East Greenland volcanic margin : constraints from 40Ar/39Ar dating of basaltic dykeS. Earth Planet. Sci. Lett., 6773, 1–14.
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Roscoe H.K., Squires J.A.C., Oldham D.J., Pommereau J.P. & Goutail F. (1994). Year round measurements of Ozone at 66°S with a visible spectrometer. Proc. Quad. Ozone Symp., NASA Conf. Pub., 3266, 569–572.
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Goutail F., Pommereau J.P. & Sarkissian A. (1994). Four years of ground-based total ozone measurements by visible spectrometry in Antarctica. Proc. Quad Ozone Symp, 3266(2), 602–605.
Abstract: Proc. Quad Ozone Symp., 602, NASA Conf. Pub. 3266, Part 2, 602, 605
Programme: 209
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Pinglot J.F. & Pourchet M. (1994). Spectrométrie gamma à trés bas niveau avec anticompton Nal(TI) pour l'étude des glaciers et des sédiments. NotecCEA, 2756, 291–296.
Abstract: NotecCEA-N-2756-ISSn 0429-3460, Paris Cea-DAMRI
Programme: 265
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Maj Emilie, Vaté Virginie. (2009). Au-delà de l'Oural.., La recherche anthropologique en Sibérie. La revue pour l’histoire du CNRS, , 41.
Abstract: An article about the anthropological research about Siberia in France since the bigenning of the XX century. website of the journal: http://histoire-cnrs.revues.org/
Programme: 1024
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Halsey, L.G., Handrich, Y., Fahlman, A., Schmidt, A., Bost, C.-A, Holder, R.L., Woakes, A.J., Butler, P.J. (2007). A fine scale analysis of diving energetics in king penguins: How behaviour affects the cost of a foraging dive. Mar. Ecol. Prog. Ser., 2007, 299–309.
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Macelloni, G.; Brogioni, M.; Santi, E. (2007). Retrieval from AMSR-E data of the snow temperature profile at Dome-C Antarctica Giovanni Macelloni (Vol. Geoscience and Remote Sensing Symposium, 2007. IGA).
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Macelloni, G.; Brogioni, M.; Vey, S. (2007). Calibration of a ground based radiometer for a one-year experiment in antarctica : A contribution to SMOS calibration (Vol. Geoscience and Remote Sensing Symposium, 2007. IGA).
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