LINK<\/strong><\/a><\/p>\n\n\n\n“Hydrogen isotopes in apatite are widely used to constrain the origin and evolution of water in Martian magmas and crustal reservoirs. However, the extent to which shock metamorphism modifies hydrogen-isotope compositions in apatites is poorly understood. In this study, we combine scanning electron microscopy (SEM), cathodoluminescence (CL), transmission electron microscopy (TEM) observations, and secondary ion mass spectrometry (SIMS) measurements of hydrogen isotopes and water contents in apatites from the Martian meteorite Los Angeles. Panchromatic CL imaging reveals distinct bright and dark domains within individual apatite grains. These domains correlate with variations in hydrogen-isotope composition, chlorine abundance, and shock metamorphic microstructures (dislocations, planar fractures, and shock-induced melting) observed at the nanoscale. Bright CL regions show higher defect densities, more abundant melt pockets, lower chlorine contents, and elevated \u03b4D values relative to dark CL regions. Defect density correlates positively with \u03b4D and melt pocket abundance but shows no systematic relationship with bulk H2O content. These observations demonstrate that hydrogen-isotope modification can occur in heavily deformed apatite without requiring complete melting or recrystallization. Shock-induced defects therefore provide pathways for hydrogen redistribution and isotopic exchange at the micron scale. The results indicate that shock metamorphism can locally modify primary hydrogen isotope signatures in Martian meteorites while preserving bulk water contents within the typical Martian apatite range. Cathodoluminescence imaging provides a rapid and non-destructive method for identifying apatite domains that can correlate with deformation-enhanced and isotopically-modified regions. These findings have important implications for interpreting Martian volatile reservoirs and for future sample-return missions such as Martian Moons eXploration (MMX).”<\/p>\n","protected":false},"excerpt":{"rendered":"
E. Dobric\u0103, J.P. Greenwood, A.N. Krot, A.J. Brearley, E.P. Vicenzi, S. Itoh, N. Sakamoto, H. Yurimoto Geochimica et Cosmochimica Acta, In Press, Journal Pre-proof, Available online 11 August 2026 LINK “Hydrogen isotopes in apatite are…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[122,43,63,181],"tags":[658,1684,206,1006,3572,4113,4899,1844,1855],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/42420"}],"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=42420"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/42420\/revisions"}],"predecessor-version":[{"id":42421,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/42420\/revisions\/42421"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=42420"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=42420"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=42420"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}