The Paris meteorite is the least altered CM carbonaceous
\nchondrite, as witnessed by the presence of unaltered metal
\ngrains and amorphous silicate, usually absent in CM
\nchondrites [1]. Its O-isotopes are intermediate between
\naltered CM and the thermally metamorphosed CO chondrites.
\nChondritic organics have most likely a multi-stage history
\nthat remains complex to disentangle, but Paris provides a
\nunique opportunity to assess the specific role of parent body
\nprocesses on their evolution. Therefore, we have studied the
\ninsoluble organic matter (IOM) of Paris and compared it to
\nIOM from Murchison and other CMs. By focusing on a single
\nchondrite group, we can rule out possible precursor influence
\nthat we encountered in a previous study of IOM in
\ncarbonaceous chondrites from different groups [2].
\nWe obtained a \u201cbulk\u201d IOM of Paris by HF\/HCl digestion
\nof a large sample (>10g) of matrix isolated by the freeze-thaw
\nmethod [1]. The bulk C, H and N-isotope compositions of
\nParis IOM fall among the heaviest CM chondrites.
\nNanoSIMS images of H and N-isotopes reveal numerous hot
\nspots. D-rich hot spots in Paris span the same range as in
\nMurchison, however 15 N-rich hot spots are significantly
\nheavier (mean value at 550\u2030, max at 1000\u2030), albeit lighter
\nthan in Bells [3]. The Raman signature points to a disordered
\nmaterial, similar to type 1 and 2 chondrites [4]. FTIR,
\nXANES and NMR reveal that Paris is intermediate between
\nCR2 and CM2 IOMs. In particular, they show that the
\naliphatic\/aromatic carbon ratio is larger in Paris than in
\nMurchison.
\nOverall, it appears that during aqueous alteration on the
\nCM parent body, IOM underwent some degree of
\naromatization in addition to slight D\/H decrease and a more
\nsignificant 15 N-rich hot spot depletion. Coupled hydrous and
\nthermal effects could explain this evolution. Paris IOM
\nappears primitive with respects to other CM and could
\nresemble to the organic matter that accreted on the CM parent
\nbody. <\/div><\/div>\n","protected":false},"excerpt":{"rendered":"
Remusat L, Vinogradoff V, Le Guillou C & Bernard S Goldschmidt 2015, Prague, 16-21 August 2015 PDF (abstract)<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,18,576],"tags":[106,105,743,1807,304],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/4793"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4793"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/4793\/revisions"}],"predecessor-version":[{"id":4794,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/4793\/revisions\/4794"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4793"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4793"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4793"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}