{"id":3754,"date":"2020-02-11T15:30:30","date_gmt":"2020-02-11T15:30:30","guid":{"rendered":"http:\/\/caribbeanlithos.ub.edu\/?p=3754"},"modified":"2026-03-04T15:25:32","modified_gmt":"2026-03-04T15:25:32","slug":"2020-fe-ti-zr-metasomatism-in-the-oceanic-mantle-due-to-extreme-differentiation-of-tholeiitic-melts-moa-baracoa-ophiolite-cuba","status":"publish","type":"post","link":"https:\/\/caribbeanlithos.ub.edu\/?p=3754","title":{"rendered":"2020: Fe-Ti-Zr metasomatism in the oceanic mantle due to extreme differentiation of tholeiitic melts (Moa-Baracoa ophiolite, Cuba)"},"content":{"rendered":"\n

Fe-Ti-Zr metasomatism in the oceanic mantle due to extreme differentiation of tholeiitic melts (Moa-Baracoa ophiolite, Cuba) <\/strong><\/p>\n\n\n\n

Abstract<\/p>\n\n\n\n

Ti-rich amphibole, Mg-rich ilmenite, baddeleyite, zirconolite, srilankite, and zircon are important high-field-strength elements (HFSE) bearing phases in the Potos\u00ed chromitite bodies located in the Moho Transition Zone of the Cretaceous Moa-Baracoa suprasubduction zone ophiolite (eastern Cuba). Such HFSE-bearing phases were found in the interaction zone between gabbroic intrusions and chromitite pods. In addition to HFSE-bearing minerals, the studied samples are composed of Fe3+<\/sup> and Ti-rich chromite, olivine (Fo86-90<\/sub>), clinopyroxene (En44-49<\/sub>), plagioclase (An51-56<\/sub>), orthopyroxene (En84-94<\/sub>), F-rich apatite, and Fe-Cu-Ni sulfides. The studied ilmenite hosting Zr oxides (baddeleyite, zirconolite, and srilankite) contains up to 13 wt.% MgO. The Potos\u00ed zirconolite is the first record of this mineral in ophiolitic chromitites and non-metamorphic ophiolite units, and it has relatively high REE contents (up to 10 wt.% of REE2<\/sub>O3<\/sub>) and the highest concentrations in Y2<\/sub>O3<\/sub> (up to 11 wt.%) reported so far in zirconolite from terrestrial occurrences. Zircon is observed forming coronas surrounding ilmenite grains in contact with silicate minerals, and is characterized by very low U and Pb contents. The zircons formed after high temperature Zr diffusion in ilmenite (exsolution) and a subsequent reaction along grain boundaries following crystallization. Finally, U-Pb dating of baddeleyite exsolutions within ilmenite yielded an average age of 134.4 \u00b1 14 Ma, which provides the first ever dating for a metasomatic event in Potos\u00ed that matches well (within uncertainty) the formation age of the oceanic crust of the eastern Cuba ophiolite. We propose that the occurrence of HFSE- and REE-bearing minerals in the Potos\u00ed chromite deposit is the result of a two stage process: first, water-rich and HFSE-rich residual melts are produced by intercumulus crystal fractionation after an evolved MORB (BABB)-like melt; and secondly, these residual melt fractions escaped the solidifying mush and extensively reacted and metasomatized the surrounding chromitites, crystallizing HFSE- and REE_bearing minerals and Fe-Cu-Ni sulfides.<\/p>\n\n\n\n

Keywords:<\/strong> ophiolitic chromitite; zircon coronas; HFSE minerals; evolved MORB melt; modal metasomatism<\/p>\n\n\n

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To Cite this article:<\/strong> Pujol-Sol\u00e0, N.; Proenza, J.A.; Garcia-Casco, A.; Gonz\u00e1lez-Jim\u00e9nez, J.M.; Rom\u00e1n-Alpiste, M.J.; Garrido, C.J.; Melgarejo, J.C.; Gervilla, F., & Llovet, X. (2020). Fe-Ti-Zr metasomatism in the oceanic mantle due to extreme differentiation of tholeiitic melts (Moa-Baracoa ophiolite, Cuba). Lithos 358-359, 105420. https:\/\/doi.org\/10.1016\/j.lithos.2020.105420
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DOI<\/strong>: 10.1016\/j.lithos.2020.105420 
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<\/p>","protected":false},"excerpt":{"rendered":"Fe-Ti-Zr metasomatism in the oceanic mantle due to extreme differentiation of tholeiitic melts (Moa-Baracoa ophiolite, Cuba) Abstract Ti-rich amphibole, Mg-rich ilmenite, baddeleyite, zirconolite, srilankite, and zircon are important high-field-strength elements (HFSE) bearing phases in the Potos\u00ed chromitite bodies located in the Moho Transition Zone of the Cretaceous Moa-Baracoa suprasubduction zone ophiolite (eastern Cuba). Such HFSE-bearing phases were found in the Continue Reading<\/a>","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[130,40,44],"tags":[],"class_list":["post-3754","post","type-post","status-publish","format-standard","hentry","category-publications2020","category-cuba","category-publications","cat-130-id","cat-40-id","cat-44-id"],"_links":{"self":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3754","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3754"}],"version-history":[{"count":3,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3754\/revisions"}],"predecessor-version":[{"id":3764,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3754\/revisions\/3764"}],"wp:attachment":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3754"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3754"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3754"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}