{"id":3541,"date":"2017-03-01T09:56:05","date_gmt":"2017-03-01T09:56:05","guid":{"rendered":"http:\/\/webfe10.fe.cpd.local\/caribbeanlithos\/?p=3541"},"modified":"2026-03-04T15:32:17","modified_gmt":"2026-03-04T15:32:17","slug":"2017-petrogenesis-of-meta-volcanic-rocks-from-the-maimon-formation-dominican-republic-geochemical-record-of-the-nascent-greater-antilles-paleo-arc","status":"publish","type":"post","link":"https:\/\/caribbeanlithos.ub.edu\/?p=3541","title":{"rendered":"2017: Petrogenesis of meta-volcanic rocks from the Maim\u00f3n Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc"},"content":{"rendered":"<p><strong>Petrogenesis of meta-volcanic rocks from the Maim\u00f3n Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc<\/strong><\/p>\n<p><u>Abstract<\/u><\/p>\n<p>Metamorphosed basalts, basaltic andesites, andesites and plagiorhyolites of the Early Cretaceous, probably pre-Albian, Maim\u00f3n Formation, located in the Cordillera Central of the Dominican Republic, are some of the earliest products of the Greater Antilles arc magmatism. In this article, new whole-rock element and Nd\u2013Pb radiogenic isotope data are used to give new insights into the petrogenesis of the Maim\u00f3n meta-volcanic rocks and constrain the early evolution of the Greater Antilles paleo-arc system. Three different groups of mafic volcanic rocks are recognized on the basis of their immobile element contents. Group 1 comprises basalts with compositions similar to low-Ti island arc tholeiites (IAT), which are depleted in light rare earth elements (LREE) and resemble the forearc basalts (FAB) and transitional FAB-boninitic basalts of the Izu-Bonin-Mariana forearc. Group 2 rocks have boninite-like compositions relatively rich in Cr and poor in TiO2. Group 3 comprises low-Ti island arc tholeiitic basalts with near-flat chondrite-normalized REE patterns. Plagiorhyolites and rare andesites present near-flat to subtly LREE-depleted chondrite normalized patterns typical of tholeiitic affinity. Nd and Pb isotopic ratios of plagiorhyolites, which are similar to those of Groups 1 and 3 basalts, support that these felsic lavas formed by anatexis of the arc lower crust.<\/p>\n<p>&nbsp;<\/p>\n<p>Geochemical modelling points that the parental basic magmas of the Maim\u00f3n meta-volcanic rocks formed by hydrous melting of a heterogeneous spinel-facies mantle source, similar to depleted MORB mantle (DMM) or depleted DMM (D-DMM), fluxed by fluids from subducted oceanic crust and Atlantic Cretaceous pelagic sediments. Variations of subduction-sensitive element concentrations and ratios from Group 1 to the younger rocks of Groups 2 and 3 generally match the geochemical progression from FAB-like to boninite and IAT lavas described in subduction-initiation ophiolites. Group 1 basalts likely formed at magmatic stages transitional between FAB and first-island arc magmatism, whereas Group 2 boninitic lavas resulted from focused flux melting and higher degrees of melt extraction in a more mature stage of subduction. Group 3 basalts probably represent magmatism taking place immediately before the establishment of a steady-state subduction regime. The relatively high extents of flux melting and slab input recorded in the Maim\u00f3n lavas support a scenario of hot subduction beneath the nascent Greater Antilles paleo-arc. Paleotectonic reconstructions and the markedly depleted, though heterogeneous character of the mantle source, indicate the rise of shallow asthenosphere which had sourced mid-ocean ridge basalts (MORB) and\/or back-arc basin basalts (BABB) in the proto-Caribbean domain prior to the inception of SW-dipping subduction. Relative to the neighbouring Aptian-Albian Los Ranchos Formation, we suggest that Maim\u00f3n volcanic rocks extruded more proximal to the vertical projection of the subducting proto-Caribbean spreading ridge.<\/p>\n<p><strong>Keywords:<\/strong> Forearc; Subduction-initiation; Ophiolite; Greater Antilles paleo-arc; Slab fluids<\/p>\n<p>----------------------------------------------------------------------------------------------------------<\/p>\n<p><strong>To Cite this article:<\/strong> Torr\u00f3, L., Proenza, J.A., Marchesi, C., Garcia-Casco, A., Lewis, J.F. (2017): Petrogenesis of meta-volcanic rocks from the Maim\u00f3n Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc. <em>Lithos<\/em>, 278-281, 255-273.<\/p>\n<p><strong>DOI<\/strong>: <a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0024493717300531\">10.1016\/j.lithos.2017.01.031.<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Petrogenesis of meta-volcanic rocks from the Maim\u00f3n Formation (Dominican Republic): Geochemical record of the nascent Greater Antilles paleo-arc Abstract Metamorphosed basalts, basaltic andesites, andesites and plagiorhyolites of the Early Cretaceous, probably pre-Albian, Maim\u00f3n Formation, located in the Cordillera Central of the Dominican Republic, are some of the earliest products of the Greater Antilles arc magmatism. In this article, new whole-rock&nbsp;<a href=\"https:\/\/caribbeanlithos.ub.edu\/?p=3541\" class=\"read-more\">Continue Reading<\/a>","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[127,42,44],"tags":[],"class_list":["post-3541","post","type-post","status-publish","format-standard","hentry","category-publications2017","category-dominicanrepublic","category-publications","cat-127-id","cat-42-id","cat-44-id"],"_links":{"self":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3541","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=3541"}],"version-history":[{"count":1,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3541\/revisions"}],"predecessor-version":[{"id":3542,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3541\/revisions\/3542"}],"wp:attachment":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3541"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3541"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3541"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}