FN Archimer Export Format
PT J
TI Element distribution in the root zone of ultramafic-hosted black smoker-like systems: Constraints from an Alpine analog
BT 
AF Coltat, R.
   Boulvais, P.
   Riegler, T.
   Pelleter, Ewan
   Branquet, Y.
AS 1:1;2:1;3:2;4:3;5:1,4;
FF 1:;2:;3:;4:PDG-REM-GM-LCG;5:;
C1 Géosciences Rennes, CNRS UMR 6118, Université Rennes, F-35000 Rennes, France
   Department of Geology, Trinity College Dublin, Dublin, Ireland
   IFREMER Centre de Brest, DRO/GM, Plouzané, France
   ISTO, UMR7327, Université d'Orléans, CNRS, BRGM, 4507ISTO1 Orléans, France
C2 UNIV RENNES, FRANCE
   TRINITY COLL DUBLIN, IRELAND
   IFREMER, FRANCE
   UNIV ORLEANS, FRANCE
SI BREST
SE PDG-REM-GM-LCG
IN WOS Ifremer UPR
   copubli-france
   copubli-europe
   copubli-univ-france
IF 4.685
TC 7
UR https://archimer.ifremer.fr/doc/00653/76559/77681.pdf
LA English
DT Article
DE ;Ultramafic-hosted black smokers;Root zones;Element distribution;Mid-oceanic ridges;Extensional detachment;Alps
AB Fluid-rock interactions at Mid-Oceanic Ridges lead to metal deposition in the so-called seafloor massive sulfides at ultramafic-hosted systems. Due to restricted access to the seafloor and scarcity of 3D exposures, these systems are poorly understood at-depth. A way to access the vertical dimension is to focus on fossil analogs preserved on-land such as the one preserved in serpentinites from the Platta nappe (SE Switzerland). For this example, we document the element distribution in the mineralized rocks at three distinct levels in the rock column using both whole rock chemical analyses and LA-ICPMS analysis of sulfide (chalcopyrite and pyrrhotite) and magnetite. We bring, for the first time, chemical signatures of the mineralization in the root zone of ultramafic-hosted black smokers. At any given depth, the Co/Ni ratio is maximum in the most mineralized samples indicating that this ratio is linked to the intensity of hydrothermal alteration. Additionally, the Co/Ni ratio decreases in mineralized rocks towards the paleosurface, whereas the Se content increases. An episode of carbonation recorded in the highest structural level of the system was responsible for a slight remobilization of the former Cu stock. We propose a model in which the uprising mineralizing fluid mixed with seawater within the host serpentinites, before venting at the paleoseafloor. 
PY 2021
PD JAN
SO Chemical Geology
SN 0009-2541
PU Elsevier BV
VL 559
UT 000600546500009
DI 10.1016/j.chemgeo.2020.119916
ID 76559
ER

EF