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Lagabrielle, Yves; Asti, Riccardo; Fourcade, Serge; Corre, Benjamin; Poujol, Marc; Uzel, Jessica; Labaume, Pierre; Clerc, Camille; Lafay, Romain; Picazo, Suzanne; Maury, Rene. |
In two companion papers, we report the detailed geological and mineralogical study of two emblematic serpentinized ultramafic bodies of the western North Pyrenean Zone (NPZ), the Urdach massif (this paper) and the Saraille massif (paper 2). The peridotites have been exhumed to lower crustal levels during the Cretaceous rifting period in the future NPZ. They are associated with Mesozoic pre-rift metamorphic sediments and small units of thinned Paleozoic basement that were deformed during the mantle exhumation event. Based on detailed geological cross-sections and microprobe mineralogical analyses, we describe the lithology of the two major extensional fault zones that accommodated: (i) the progressive exhumation of the lherzolites along the Cretaceous basin... |
Tipo: Text |
Palavras-chave: North Pyrenean Zone; Urdach; Mantle exhumation; Fluid-rock interactions; Listvenites; Greenschist facies; Detachment faults; Late Cretaceous. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00637/74920/76106.pdf |
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Coltat, Rémi; Branquet, Yannick; Gautier, Pierre; Campos Rodriguez, Hector; Poujol, Marc; Pelleter, Ewan; Mcclenaghan, Sean; Manatschal, Gianreto; Boulvais, Philippe. |
Mid‐Ocean Ridges host various types of hydrothermal systems including high‐T black‐smokers found in ultramafic rocks exhumed along slow spreading ridges. These systems are mostly described in two dimensions as their exposure on the present‐day seafloor lacks the vertical dimension. One way to understand these systems at depth is to study their fossilized equivalents preserved on‐land. Such observation can be done in the Platta nappe, Switzerland, where a Jurassic‐aged mineralized system is exposed in 3D. Serpentinites host a Cu‐Fe‐Ni‐Co‐Zn‐rich mineralization made of sulphides, magnetite and Fe‐Ca‐silicates either replacing serpentinites or within stockwork. Fe‐Ca‐silicates, abundant at the deepest levels, vanish in the mineralization close to the... |
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Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00588/70028/68013.pdf |
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