S and O chemical analysis of aqueously altered carbonaceous chondrites IOM

• Main Authors: Orthous-Daunay, François-Regis, Quirico, Eric, Lemelle, Laurence, Beck, Pierre, de Andrade, V., Simionovici, Alexandre, Derenne, S., Schmitt, Bernard
• Other Authors: Laboratoire de Planétologie de Grenoble (LPG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Sciences de la Terre (LST), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ID21 Beamline, European Synchrotron Radiation Facility (ESRF), Laboratoire de Géodynamique des Chaines Alpines (LGCA), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Biogéochimie et écologie des milieux continentaux (Bioemco), École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2009
• Subjects: [SDU]Sciences of the Universe [physics]; Tagish
• Online Access: https://insu.hal.science/insu-00367916

CI, CM, CR and ungrouped C2 carbonaceous chondrites contain a few percents of insoluble organic matter (IOM), which could have a presolar origin and provide clues on carbon chemistry in interstellar medium of protostellar environments. However, these chondrites have experienced complex hydrothermal processes in their parent bodies [1-3]. A major issue is the understanding of chemical changes in composition and structure of IOM due to aqueous alteration. Chemical variations have been reported among various chondrites, and so far interpreted as the consequence of oxidation processes by some authors [4; 5]. Variations among the precursors accreted can also be suspected [6]. We measured by micro-infrared spectroscopy (at LPG, Grenoble) and sulfur XANES at the K-edge (at ESRF, ID21, Grenoble) a series of IOMs extracted from CI1 (Ivuna, Orgueil, Alais), CM2 (Murchison, Cold Bokkeveld, QUE99355, QUE97990, Mighei and Murray), CR2 (Renazzo) and C2 ungrouped (Tagish Lake) chondrites. Only CIs and Cold Bokkeveld have strong carboxylic IR bands and oxidised organic sulfur XANES features. Neither XANES and IR show major variability within one group. These results evidence systematic differences between C1 and other C2 chondrites. Cold Bokkeveld appears as a peculiar object, and should be considered as an anomalous CM2. The lack of organic oxidation trend going with alteration gradient makes us say : i) hydrothermalism was very stronger on C1 parent body than on C2's and ii) oxidation of different precursors of C1 and C2 may have an effect on the IOM.