LINK<\/strong><\/a><\/p>\n\n\n\n“Ordinary chondrites record shock metamorphism resulting from hypervelocity collisions on small bodies, and underpin the petrographic assessment of shock stage, a scale of progressive stages of shock metamorphism from S1 (unshocked) to S7 (shock melted). In this work, olivine grains in 11 L and LL chondrites (S1\u2013S5) were investigated in thin section and hand sample using in situ two\u2010dimensional X\u2010ray diffraction (2\u2010D XRD). Olivine grains were measured under a 300 \u00b5m X\u2010ray beam for multiple lattice reflections, by measuring diffracted streak length along the chi (\u03c7) dimension (Debye ring dimension), to examine their strain\u2010related mosaicity. Olivine strain\u2010related mosaicity was observed to increase with greater shock deformation, with more complex multi\u2010peak streaks apparent at higher shock levels. The full width at half maximum (FWHM\u03c7) of the simple peak shapes along \u03c7 was measured to quantify petrographic shock stage for comparison with that described optically. The average FWHM\u03c7 values for simple peaks in olivine show an increase with increasing shock stage: S1 (0.44\u00b0\u00b1 0.06\u00b0), S2 (0.58\u00b0\u00b1 0.11\u00b0), S3 (0.67\u00b0\u00b1 0.15\u00b0), S4 (0.76\u00b0\u00b1 0.13\u00b0), and S5 (0.86\u00b0\u00b1 0.12\u00b0). This method complements optical petrographic methods and offers a \u00b11 shock stage accuracy in determining shock stage. In particular, 2\u2010D XRD analysis of strain\u2010related mosaicity allows quantitative analysis of shock stage in shock\u2010darkened samples that are difficult to work with petrographically, and for hand samples without need for thin section preparation.”<\/p>\n","protected":false},"excerpt":{"rendered":"
Alexandra N. Rupert, Phil J.A. McCausland, Roberta L. Flemming Meteoritics & Planetary ScienceVersion of Record online:21 September 2020 LINK “Ordinary chondrites record shock metamorphism resulting from hypervelocity collisions on small bodies, and underpin the petrographic…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23,24,7,63],"tags":[3037,1844],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/23868"}],"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=23868"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/23868\/revisions"}],"predecessor-version":[{"id":23869,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/23868\/revisions\/23869"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=23868"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=23868"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=23868"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}