LINK<\/strong><\/a><\/p>\n“Highlights
\n\u2022 We dated the Clearwater Lake impact craters (Canada) via the (U\u2013Th)\/He zircon method.
\n\u2022 Results presented here indicate that the adjacent twin craters formed \u223c170 Ma apart.
\n\u2022 Suggesting Clearwater East and West impact craters do not comprise an impact doublet.”<\/p>\n
“The (U\u2013Th)\/He method has been applied to constrain the formation ages of the Clearwater West and East impact structures of Quebec, Canada. Zircons were separated from impact melt samples derived from a surface exposure at Clearwater West (32 km diameter), and from a drill core at Clearwater East (26 km diameter). The (U\u2013Th)\/He results indicate ages of 280\u00b127 Ma280\u00b127 Ma (2\u03c3 , n=7n=7) for Clearwater West, and 450\u00b156 Ma450\u00b156 Ma (2\u03c3 , n=8n=8) for Clearwater East. Our (U\u2013Th)\/He date for Clearwater West supports the findings of previous Rb\u2013Sr (266\u00b115 Ma266\u00b115 Ma; 2\u03c3) and 40Ar\/39Ar (280\u00b14 Ma280\u00b14 Ma and 283.8\u00b12.2 Ma283.8\u00b12.2 Ma, 2\u03c3) impact melt studies. Our (U\u2013Th)\/He date for Clearwater East also overlaps with previously published 40Ar\/39Ar dating results, which yielded U-shaped spectra, with \u2018maximum\u2019 and \u2018best-estimate\u2019 dates of \u223c 460\u2013470 Ma. Our results support the contention, previously based solely on 40Ar\/39Ar data, that the Clearwater West and East impact structures do not comprise an impact doublet that formed coevally from a binary asteroid pair.”<\/p>\n","protected":false},"excerpt":{"rendered":"
M.B. Biren, M.C. van Soest, J.-A. Wartho, K.V. Hodges, J.G. Spray Earth and Planetary Science Letters Volume 453, 1 November 2016, Pages 56\u201366 LINK “Highlights \u2022 We dated the Clearwater Lake impact craters (Canada) via…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[284,90,68],"tags":[3195,3192,91,3193,3194,3196,92,1848,2199],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/9652"}],"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=9652"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/9652\/revisions"}],"predecessor-version":[{"id":9653,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/9652\/revisions\/9653"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=9652"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=9652"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=9652"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}