{"id":16027,"date":"2018-08-01T09:04:18","date_gmt":"2018-08-01T07:04:18","guid":{"rendered":"http:\/\/karmaka.de\/?p=16027"},"modified":"2018-08-01T09:04:18","modified_gmt":"2018-08-01T07:04:18","slug":"evaluation-of-petrologic-evidence-for-high-partial-pressures-of-siog-in-the-solar-nebula","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=16027","title":{"rendered":"Evaluation of petrologic evidence for high partial pressures of SiO(g) in the solar nebula"},"content":{"rendered":"<p>Alan E. Rubin <\/p>\n<p><a href=\"https:\/\/onlinelibrary.wiley.com\/doi\/full\/10.1111\/maps.13180\" target=\"_blank\"><strong>LINK<\/strong><\/a><\/p>\n<p>Meteorit Planet Sci. . doi:10.1111\/maps.13180<\/p>\n<p>&#8220;Although they cannot be ruled out, high partial pressures of SiO(g) in the solar nebula are not required to produce various petrologic features of chondrules. These features include the low\u2010Ca\u2010pyroxene\u2010rich margins of type\u2010IAB chondrules, high concentrations of SiO2 and Na2O in mesostasis near the surface of some chondrules in LL3.0 Semarkona, and silica\u2010rich igneous rims around many type\u2010I chondrules in CR chondrites. It is a misconception that low\u2010Ca pyroxene phenocrysts are restricted mainly to the periphery of type\u2010IAB chondrules; instead, they are widely distributed in most of these chondrules. Type\u2010IAB chondrules can be modeled as having formed by remelting of type\u2010IB chondrules that contained relict olivine grains derived from disrupted type\u2010IA chondrules. Semarkona chondrule mesostases that show increased concentrations of SiO2 and Na2O from the core to the rim were probably affected by parent\u2010body aqueous alteration. The silica\u2010rich igneous rims around many type\u2010I chondrules in CR chondrites may have formed by melting of pyroxene\u2010rich dust aggregates that had been previously enriched in Na, K, and Mn derived from volatilized chondrules. &#8220;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Alan E. Rubin LINK Meteorit Planet Sci. . doi:10.1111\/maps.13180 &#8220;Although they cannot be ruled out, high partial pressures of SiO(g) in the solar nebula are not required to produce various petrologic features of chondrules. These&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[56,148,12],"tags":[1839,3616,4633,4630,158,2304,1219,4632,4631],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/16027"}],"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=16027"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/16027\/revisions"}],"predecessor-version":[{"id":16028,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/16027\/revisions\/16028"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16027"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16027"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16027"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}