Research output: Contribution to journal › Article › peer-review
Contrasted hydrothermal activity along the South-East Indian Ridge (130°E–140°E) : From crustal to ultramafic circulation. / Boulart, Cédric; Briais, Anne; Chavagnac, Valérie; Révillon, Sidonie; Ceuleneer, Georges; Donval, Jean Pierre; Guyader, Vivien; Barrere, Fabienne; Ferreira, Nicolas; Hanan, Barry; Hémond, Christophe; Macleod, Sarah; Maia, Marcia; Maillard, Agnès; Merkuryev, Sergey; Park, Sung Hyun; Ruellan, Etienne; Schohn, Alexandre; Watson, Sally; Yang, Yun Seok.
In: Geochemistry, Geophysics, Geosystems, Vol. 18, No. 7, 01.01.2017, p. 2446-2458.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Contrasted hydrothermal activity along the South-East Indian Ridge (130°E–140°E)
T2 - From crustal to ultramafic circulation
AU - Boulart, Cédric
AU - Briais, Anne
AU - Chavagnac, Valérie
AU - Révillon, Sidonie
AU - Ceuleneer, Georges
AU - Donval, Jean Pierre
AU - Guyader, Vivien
AU - Barrere, Fabienne
AU - Ferreira, Nicolas
AU - Hanan, Barry
AU - Hémond, Christophe
AU - Macleod, Sarah
AU - Maia, Marcia
AU - Maillard, Agnès
AU - Merkuryev, Sergey
AU - Park, Sung Hyun
AU - Ruellan, Etienne
AU - Schohn, Alexandre
AU - Watson, Sally
AU - Yang, Yun Seok
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Using a combined approach of seafloor mapping, MAPR and CTD survey, we report evidence for active hydrothermal venting along the 130°-140°E section of the poorly-known South-East Indian Ridge (SEIR) from the Australia-Antarctic Discordance (AAD) to the George V Fracture Zone (FZ). Along the latter, we report Eh and CH4 anomalies in the water column above a serpentinite massif, which unambiguously testify for ultramafic-related fluid flow. This is the first time that such circulation is observed on an intermediate-spreading ridge. The ridge axis itself is characterized by numerous off-axis volcanoes, suggesting a high magma supply. The water column survey indicates the presence of at least ten distinct hydrothermal plumes along the axis. The CH4:Mn ratios of the plumes vary from 0.37 to 0.65 denoting different underlying processes, from typical basalt-hosted to ultramafic-hosted high-temperature hydrothermal circulation. Our data suggest that the change of mantle temperature along the SEIR not only regulates the magma supply, but also the hydrothermal activity. The distribution of hydrothermal plumes from a ridge segment to another implies secondary controls such as the presence of fractures and faults along the axis or in the axial discontinuities. We conclude from these results that hydrothermal activity along the SEIR is controlled by magmatic processes at the regional scale and by the tectonics at the segment scale, which influences the type of hydrothermal circulation and leads to various chemical compositions. Such variety may impact global biogeochemical cycles, especially in the Southern Ocean where hydrothermal venting might be the only source of nutrients.
AB - Using a combined approach of seafloor mapping, MAPR and CTD survey, we report evidence for active hydrothermal venting along the 130°-140°E section of the poorly-known South-East Indian Ridge (SEIR) from the Australia-Antarctic Discordance (AAD) to the George V Fracture Zone (FZ). Along the latter, we report Eh and CH4 anomalies in the water column above a serpentinite massif, which unambiguously testify for ultramafic-related fluid flow. This is the first time that such circulation is observed on an intermediate-spreading ridge. The ridge axis itself is characterized by numerous off-axis volcanoes, suggesting a high magma supply. The water column survey indicates the presence of at least ten distinct hydrothermal plumes along the axis. The CH4:Mn ratios of the plumes vary from 0.37 to 0.65 denoting different underlying processes, from typical basalt-hosted to ultramafic-hosted high-temperature hydrothermal circulation. Our data suggest that the change of mantle temperature along the SEIR not only regulates the magma supply, but also the hydrothermal activity. The distribution of hydrothermal plumes from a ridge segment to another implies secondary controls such as the presence of fractures and faults along the axis or in the axial discontinuities. We conclude from these results that hydrothermal activity along the SEIR is controlled by magmatic processes at the regional scale and by the tectonics at the segment scale, which influences the type of hydrothermal circulation and leads to various chemical compositions. Such variety may impact global biogeochemical cycles, especially in the Southern Ocean where hydrothermal venting might be the only source of nutrients.
KW - hydrothermal plumes
KW - mid-ocean ridges
KW - South-East Indian Ridge
UR - http://www.scopus.com/inward/record.url?scp=85021726592&partnerID=8YFLogxK
U2 - 10.1002/2016GC006683
DO - 10.1002/2016GC006683
M3 - Article
AN - SCOPUS:85021726592
VL - 18
SP - 2446
EP - 2458
JO - Geochemistry, Geophysics, Geosystems
JF - Geochemistry, Geophysics, Geosystems
SN - 1525-2027
IS - 7
ER -
ID: 51325117