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Clement, Jean-philippe; Caroff, Martial; Dudoignon, Patrick; Launeau, Patrick; Bohn, Marcel; Cotten, Joseph; Blais, Sylvain; Guille, Gérard. |
This paper reports new field observations and new petrological, textural and geochemical data on two gabbroic intrusions and one pegmatoid dyke from the French Polynesian islands Maupiti and Bora Bora, respectively. Olivine crystals from the Faataufi and Barque de Hiro gabbros (Maupiti) include High Temperature Iddingsite (HTI), exhibiting three distinct morphological facies. Chemical and crystallographical data performed by electron microprobe, scanning microscope, X-ray diffractometry and Near InfraRed spectroscopy show that HTI results from modifications of olivine structure through intense hydroxylation and Fe-oxidation. The HTI-free 120 m-wide Cloche de Hiro dyke (Bora Bora) exhibits a textural zonation from heterogranular/intergranular gabbro... |
Tipo: Text |
Palavras-chave: Society Islands; French Polynesia; Pegmatoid; Vapor differentiation; Olivine; Gabbros. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2999.pdf |
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