LINK<\/strong><\/a><\/p>\n\n\n\n“The LL5 chondrite Chelyabinsk has had numerous isotopic studies since its fall in 2013. These data have been used to suggest ~8 impact events recorded from multiple isotopic systems (e.g., Ar-Ar, U\u2013Pb, Sm-Nd, Rb-Sr, among others). We report details of Ar-Ar and U-Pb results and re-evaluate the geochronology of Chelyabinsk. Argon has the youngest Ar-Ar age recorded in meteorites, 25\u2009\u00b1\u200911\u2009Ma, and an older resetting event at ~2550\u2009Ma. The U-Pb analysis has an upper concordia age of 4456\u2009\u00b1\u200923\u2009Ma and a lower concordia age of 184\u2009\u00b1\u2009200\u2009Ma. The lower concordia intercept represents a later thermal event (e.g., an impact), the most recent time that lead loss occurred, and could represent resetting by the youngest event recorded by Ar-Ar. Combining our data with literature results, we find strong evidence of at least four impact events (~4450, 2550, 1700, 25\u2009Ma), with some evidence for two additional impacts (~3700, 1000\u2009Ma).”<\/p>\n","protected":false},"excerpt":{"rendered":"
Sky P. Beard, Timothy D. Swindle, Thomas J. Lapen, David A. Kring MAPS, Version of Record online: 01 December 2022 LINK “The LL5 chondrite Chelyabinsk has had numerous isotopic studies since its fall in 2013….<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48,24,7,68],"tags":[550,1833,2553,1816,1807,664,1832],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31644"}],"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=31644"}],"version-history":[{"count":2,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31644\/revisions"}],"predecessor-version":[{"id":31646,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/31644\/revisions\/31646"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=31644"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=31644"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=31644"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}