LINK<\/strong><\/a><\/p>\n“Bulk meteorite samples of various chemical classes and petrologic types (mainly carbonaceous chondrites) were systematically investigated by the stepped combustion method with the simultaneous isotopic analysis of carbon, nitrogen, and noble gases. A correlation was revealed between planetary noble gases associating with the Q phase and isotopically light nitrogen (\u03b415N up to \u2013150\u2030). The analysis of this correlation showed that the isotopically light nitrogen (ILN) is carried by Q. In most meteorites, isotopically heavy nitrogen (IHN) of organic compounds (macromolecular material) is dominant. The ILN of presolar grains (diamond and SiC) and Q can be detected after separation from dominant IHN. Such a separation of nitrogen from Q and macromolecular material occurs under natural conditions and during laboratory stepped combustion owing to Q shielding from direct contact with oxygen, which results in Q oxidation at temperatures higher than the temperatures of the release of most IHN. There are arguments that ILN released at high temperature cannot be related to nanodiamond and SiC. The separation effect allowed us to constrain the contents of noble gases in Q, assuming that this phase is carbon-dominated. The directly measured 36Ar\/C and 132Xe\/C ratios in ILN-rich temperature fractions are up to 0.1 and 1 \u00d7 10\u20134 cm3\/g, respectively. These are only lower constraints on the contents. The analysis of the obtained data on the three-isotope diagram \u03b415N\u201336Ar\/14N showed that Q noble gases were lost to a large extent from most meteorites during the metamorphism of their parent bodies. Hence, the initial contents of noble gases in Q could be more than an order of magnitude higher than those directly measured. Compared with other carbon phases, Q was predominantly transformed to diamond in ureilites affected by shock metamorphism. The analysis of their Ar\u2013N systematics showed that, similar to carbonaceous chondrites, noble gases were lost from Q probably before its transformation to diamond.”<\/p>\n","protected":false},"excerpt":{"rendered":"
A. B. Verchovsky Geochemistry International November 2017, Volume 55, Issue 11, pp 957\u2013970 Original Russian Text \u00a9 A.B. Verchovsky, 2017, published in Geokhimiya, 2017, No. 11, pp. 969\u2013983 LINK “Bulk meteorite samples of various chemical…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,506,39],"tags":[3273,654,4284],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/13899"}],"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=13899"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/13899\/revisions"}],"predecessor-version":[{"id":13900,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/13899\/revisions\/13900"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=13899"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=13899"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=13899"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}