{"id":38610,"date":"2025-06-19T08:31:13","date_gmt":"2025-06-19T06:31:13","guid":{"rendered":"https:\/\/karmaka.de\/?p=38610"},"modified":"2025-06-19T08:31:14","modified_gmt":"2025-06-19T06:31:14","slug":"chromium-isotopes-in-cr-chondrites-reveal-two-distinct-chondrule-reservoirs","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=38610","title":{"rendered":"Chromium isotopes in CR chondrites reveal two distinct chondrule reservoirs<span class=\"badge-status\" style=\"background:#787878\">OPEN ACCESS<\/span>&nbsp;"},"content":{"rendered":"\n<p>Aryavart Anand, Klaus Mezger<\/p>\n\n\n\n<p>Icarus, In Press, Journal Pre-proof, Available online 18 June 2025<\/p>\n\n\n\n<p><a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0019103525002623\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK + PDF (OPEN ACCESS)<\/strong><\/a><br>&#8220;Highlights<\/p>\n\n\n\n<ul>\n<li>Chondrules from CR chondrite show bimodal \u03b554Cr values.<\/li>\n\n\n\n<li>Low-\u03b554Cr chondrules match CV-CO-CM.<\/li>\n\n\n\n<li>Two isotopically distinct chondrule populations in CR imply disk-gap migration.<\/li>\n\n\n\n<li>53Mn-53Cr systematics date early precursor Mn-Cr fractionation to ~0.7\u202fMa after CAIs.&#8221;<\/li>\n<\/ul>\n\n\n\n<p class=\"justify-text\">&#8220;Chondrules, the dominant components of chondrites, provide crucial insights into early solar system formation and evolution. Due to the variability of Cr isotopes in the solar system, they can serve as powerful tracers of chondrule genealogy and the transport of precursor materials in the evolving solar disk. High-precision mass-independent Cr isotope data for individual chondrules from the CR chondrite Shi\u015fr 033 reveal a bimodal distribution of \u03b554Cr that defines two isotopically distinct chondrule populations. The major population exhibits \u03b554Cr values (~1.3) consistent with prior analyses of CR chondrules, while a minor population has significantly lower \u03b554Cr (~0.8), overlapping with CV-CO-CM chondrules. This suggests chondrule migration across spatial gaps in the protoplanetary disk, likely from the CV-CO-CM reservoir to the CR sub-reservoir. Further, 53Mn-53Cr systematics indicate that Mn-Cr fractionation in CR chondrule precursors occurred ~0.7\u202fMa after solar system formation, predating the primary CR chondrule formation event at ~3.8\u202fMa, inferred from 26Al-26Mg, and 182Hf-182W chronometry of individual chondrules. These findings support a model in which secondary disk substructures, likely linked to early Jupiter growth, facilitated isotopic heterogeneities and material transport in the outer solar system. The presence of CV-CO-CM chondrules in CR chondrites further suggests outward material transport in the protoplanetary disk before CR parent body accretion. This study provides new constraints on chondrule formation, precursor evolution, and planetary disk dynamics.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Aryavart Anand, Klaus Mezger Icarus, In Press, Journal Pre-proof, Available online 18 June 2025 LINK + PDF (OPEN ACCESS)&#8220;Highlights &#8220;Chondrules, the dominant components of chondrites, provide crucial insights into early solar system formation and evolution&#8230;.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,56,148,1607,12],"tags":[852,5830,4859,3273,1864,3614,1614,1611,2606,1564,1810,2268,458,683],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/38610"}],"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=38610"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/38610\/revisions"}],"predecessor-version":[{"id":38611,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/38610\/revisions\/38611"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=38610"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=38610"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=38610"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}