LINK<\/strong><\/a><\/p>\n\n\n\n“We report new high-precision stable K isotope data for thirty achondrites, including three martian meteorites, one lunar meteorite, one ordinary chondrite, four terrestrial igneous United States Geological Survey (USGS) reference materials, and twenty howardite\u2013eucrite\u2013diogenite [HED] meteorites. The four martian samples define a relatively narrow \u03b441K range with an average of \u22120.36 \u00b1 0.12\u2030 (2 SD) that is slightly heavier than the Bulk Silicate Earth (BSE) K isotopic composition (\u22120.48 \u00b1 0.03\u2030). Except for the four Northwest Africa samples which were terrestrially contaminated, all HED meteorites reveal substantial 41K enrichment compared to BSE, lunar samples, martian meteorites, and chondrites. We propose that the average \u03b441K (+0.36 \u00b1 0.16\u2030) obtained from HED meteorites is representative of Bulk Silicate 4-Vesta. The coupled volatile depletion and heavy K isotope enrichment in 4-Vesta could be attributed to both nebula-scale processes and parent-body events. The asteroid 4-Vesta is likely to have accreted from planetary feedstocks that have been significantly volatile-depleted prior to the major phases of planetary accretion in the early Solar System, with secondary effects of K loss during accretionary growth and magma ocean degassing.”<\/p>\n","protected":false},"excerpt":{"rendered":"
Zhen Tian, Heng Chen, Bruce Fegley, Katharina Lodders, Jean-Alix Barrat, James M.D.Day, Kun Wang (\u738b\u6606) Geochimica et Cosmochimica Acta In Press, Journal Pre-proof, Available online 21 August 2019 LINK “We report new high-precision stable K…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36,35,33,34,41,42],"tags":[5146,1824,1823,212,1822,5103,3236,1872],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20316"}],"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=20316"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20316\/revisions"}],"predecessor-version":[{"id":20317,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/20316\/revisions\/20317"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=20316"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=20316"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=20316"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}