{"id":39971,"date":"2025-12-28T22:40:38","date_gmt":"2025-12-28T21:40:38","guid":{"rendered":"https:\/\/karmaka.de\/?p=39971"},"modified":"2025-12-28T22:40:39","modified_gmt":"2025-12-28T21:40:39","slug":"late-aqueous-activity-on-vesta","status":"publish","type":"post","link":"https:\/\/karmaka.de\/?p=39971","title":{"rendered":"Late Aqueous Activity on Vesta"},"content":{"rendered":"\n<p>Tianjing Gao, Weibiao Hsu<\/p>\n\n\n\n<p>JGR Planets, First Published: 27 December 2025<\/p>\n\n\n\n<p><a href=\"https:\/\/agupubs.onlinelibrary.wiley.com\/doi\/10.1029\/2025JE009178\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>LINK<\/strong><\/a><\/p>\n\n\n\n<p>&#8220;Key Points<\/p>\n\n\n\n<ul>\n<li>Apatite veins in a plagioclase-rich clast indicate fluid-assisted metasomatism on Vesta with a Pb-Pb age of 4,169 \u00b1 85 Ma<\/li>\n\n\n\n<li>Isotopic compositions (87Sr\/86Sr and \u039417O) of the clast suggest fluids derived from primitive sources, likely carbonaceous chondrites<\/li>\n\n\n\n<li>Veneneia crater on Vesta was probably excavated by carbonaceous impactors during the late heavy bombardment&#8221;<\/li>\n<\/ul>\n\n\n\n<p class=\"justify-text\">&#8220;Fluid-assisted metasomatism was prevalent on Vesta, but the timing and source(s) of aqueous activities remain elusive. Here, we report an absolute 207Pb\/206Pb isochron age (4,169 \u00b1 85 Ma) of apatites from a plagioclase-rich eucrite clast within the Jikharra 001 eucrite. Petrographic, mineralogical, and geochemical characteristics demonstrate that apatite veins in the clast formed during fluid-assisted metasomatism on Vesta. The elevated 87Sr\/86Sr ratios observed in the bulk clast and plagioclase grains suggest the incorporation of fluid from primitive sources, probably carbonaceous chondrites. The slightly negative oxygen isotopic composition (\u039417O = \u22120.275 \u00b1 0.013\u2030) of the clast further indicates a largely carbonaceous chondrite source. Impacts from carbonaceous chondrites are the probable origin of Veneneia. Evidence from apatite veins in the Jikharra 001 is consistent with a carbonaceous fluid source and may constrain the age of Veneneia to the late heavy bombardment, approximately 4.1\u20134.2 Ga.&#8221;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tianjing Gao, Weibiao Hsu JGR Planets, First Published: 27 December 2025 LINK &#8220;Key Points &#8220;Fluid-assisted metasomatism was prevalent on Vesta, but the timing and source(s) of aqueous activities remain elusive. Here, we report an absolute&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,3249,3177,35,186],"tags":[5708,3270,2541,3389,658,3273,1823,3267,944,2343,7029,1866,1935],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39971"}],"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=39971"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39971\/revisions"}],"predecessor-version":[{"id":39972,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/39971\/revisions\/39972"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=39971"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=39971"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=39971"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}