FN Archimer Export Format
PT J
TI Tectonic structure, lithology, and hydrothermal signature of the Rainbow massif (Mid-Atlantic Ridge 36°14′N)
BT 
AF ANDREANI, Muriel
   ESCARTIN, Javier
   DELACOUR, Adelie
   ILDEFONSE, Benoit
   GODARD, Marguerite
   DYMENT, Jerome
   FALLICK, Anthony E.
   FOUQUET, Yves
AS 1:1;2:2;3:3;4:4;5:4;6:2;7:5;8:6;
FF 1:;2:;3:;4:;5:;6:;7:;8:PDG-REM-GM-LGM;
C1 Univ Lyon 1, ENS, Lab Geol Lyon, UMR 5672, F-69365 Lyon, France.
   CNRS, Inst Phys Globe Paris, UMR 7154, Paris, France.
   Univ St Etienne, CNRS, UMR 6524, Lab Magmas & Volcans, St Etienne, France.
   Univ Montpellier 2, CNRS, UMR 5243, Geosci Montpellier, Montpellier, France.
   Scottish Univ Environm Res Ctr, Glasgow, Lanark, Scotland.
   IFREMER, Ctr Brest, Plouzane, France.
C2 UNIV LYON, FRANCE
   CNRS, FRANCE
   UNIV ST ETIENNE, FRANCE
   UNIV MONTPELLIER, FRANCE
   UNIV SCOTTISH ENVIRONM RES CTR, UK
   IFREMER, FRANCE
SI BREST
SE PDG-REM-GM-LGM
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-europe
   copubli-univ-france
IF 2.923
TC 55
TU Centre national de la recherche scientifique
   Institut National de l'Information Géographique et Forestière
   Institut de physique du globe
   Institut de recherche pour le développement
   Université Blaise Pascal
   Université Claude Bernard - Lyon 1
   Université Jean Monnet Saint-Étienne
   Université Paris Diderot
   Université Pierre et Marie Curie
   Université de La Réunion
   Université de Montpellier
   Université des Antilles
   École normale supérieure de Lyon
UR https://archimer.ifremer.fr/doc/00210/32151/30609.pdf
   https://archimer.ifremer.fr/doc/00210/32151/30610.pdf
LA English
DT Article
CR FLORES
   IRIS
   MOMARDREAM-NAUT1-NAUT2
   SEAHMA 1
BO L'Atalante
   Pourquoi pas ?
DE ;rainbow;hydrothermal;serpentinization;Atlantic ridge
AB Rainbow is a dome-shaped massif at the 36°14′N nontransform offset along the Mid-Atlantic Ridge. It hosts three ultramafic-hosted hydrothermal sites: Rainbow is active and high temperature; Clamstone and Ghost City are fossil and low temperature. The MoMARDREAM cruises (2007, 2008) presented here provided extensive rock sampling throughout the massif that constrains the geological setting of hydrothermal activity. The lithology is heterogeneous with abundant serpentinites surrounding gabbros, troctolites, chromitites, plagiogranites, and basalts. We propose that a W dipping detachment fault, now inactive, uplifted the massif and exhumed these deep-seated rocks. Present-day deformation is accommodated by SSW-NNE faults and fissures, consistent with oblique teleseismic focal mechanisms and stress rotation across the discontinuity. Faults localize fluid flow and control the location of fossil and active hydrothermal fields that appear to be ephemeral and lacking in spatiotemporal progression. Markers of high-temperature hydrothermal activity (∼350°C) are restricted to some samples from the active field while a more diffuse, lower temperature hydrothermal activity (<220°C) is inferred at various locations through anomalously high As, Sb, and Pb contents, attributed to element incorporation in serpentines or microscale-sulfide precipitation. Petrographic and geochemical analyses show that the dominant basement alteration is pervasive peridotite serpentinization at ∼160–260°C, attributed to fluids chemically similar to those venting at Rainbow, and controlled by concomitant alteration of mafic-ultramafic units at depth. Rainbow provides a model for fluid circulation, possibly applicable to hydrothermalism at oceanic detachments elsewhere, where both low-temperature serpentinization and magmatic-driven high-temperature outflow develop contemporaneously, channeled by faults in the footwall and not along the detachment fault.
PY 2014
PD SEP
SO Geochemistry Geophysics Geosystems
SN 1525-2027
PU Amer Geophysical Union
VL 15
IS 9
UT 000343970900004
BP 3543
EP 3571
DI 10.1002/2014GC005269
ID 32151
ER

EF