{"id":17324,"date":"2019-02-03T11:15:01","date_gmt":"2019-02-03T10:15:01","guid":{"rendered":"http:\/\/karmaka.de\/?p=17324"},"modified":"2019-02-03T11:17:08","modified_gmt":"2019-02-03T10:17:08","slug":"the-vanadium-isotopic-composition-of-lunar-basalts","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=17324","title":{"rendered":"The vanadium isotopic composition of lunar basalts<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>S.S. Hopkins, J. Prytulak, J. Barling, S.S. Russell, B.J. Coles, A.N. Halliday<\/p>\n\n\n\n<p>Earth and Planetary Science Letters<br>\nVolume 511, 1 April 2019, Pages 12-24<\/p>\n\n\n\n<p><a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0012821X19300184#ac0010\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK (OPEN ACCESS)<\/strong><\/a><br><\/p>\n\n\n\n<p>&#8220;Highlights<\/p>\n\n\n\n<p>\u2022    We present the first measurements of vanadium (V) isotopes ratios in lunar samples.<br>\n\u2022    Lunar basalts show an isotopic range larger than all terrestrial igneous rocks.<br>\n\u2022    Magmatic processes on the Moon do not control isotopic variability.<br>\n\u2022    Cosmogenic processes control the isotopic variability observed.<br>\n\u2022    Pre-exposure V isotope ratios are similar for BSE, Moon, chondrites, and Mars.&#8221;<\/p>\n\n\n\n<p class=\"justify-text\">&#8220;We present the first high-precision vanadium (V) isotope data for lunar basalts. Terrestrial magmatic rock measurements can display significant V isotopic fractionation (particularly during (Fe, Ti)oxide crystallisation), but the Earth displays heavy V (i.e. higher 51V\/50V) isotopic compositions compared to meteorites. This has been attributed to early irradiation of meteorite components or nucleosynthetic heterogeneity. The Moon is isotopically-indistinguishable from the silicate Earth for many refractory elements and is expected to be similar in its V isotopic composition.<\/p>\n\n\n\n<p>Vanadium isotope ratios and trace element concentrations were measured for 19 lunar basalt samples. Isotopic compositions are more variable (\u223c2.5\u2030) than has been found thus far for terrestrial igneous rocks and extend to lighter values. Magmatic processes do not appear to control the V isotopic composition, despite the large range in oxide proportions in the suite. Instead, the V isotopic compositions of the lunar samples are lighter with increasing exposure age (<br>\n). Modelling nuclear cross-sections for V production and burnout demonstrates that cosmogenic production may affect V isotope ratios via a number of channels but strong correlations between V isotope ratios and \u204e [Fe]\/[V] implicate Fe as the primary target element of importance. Similar correlations are found in the latest data for chondrites, providing evidence that most V isotope variation in chondrites is due to recent cosmogenic production via Fe spallation. Contrary to previous suggestions, there is no evidence for resolvable differences between the primary V isotopic compositions of the Earth, Moon, chondrites and Mars.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>S.S. Hopkins, J. Prytulak, J. Barling, S.S. Russell, B.J. Coles, A.N. Halliday Earth and Planetary Science Letters Volume 511, 1 April 2019, Pages 12-24 LINK (OPEN ACCESS) &#8220;Highlights \u2022 We present the first measurements of&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[41],"tags":[1827,3125,414],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17324"}],"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=17324"}],"version-history":[{"count":4,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17324\/revisions"}],"predecessor-version":[{"id":17328,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/17324\/revisions\/17328"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=17324"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17324"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17324"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}