Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?

ABSTRACT The rifting zone of Bransfield Strait, Antarctica, is tectonically and geologically unique. It is a back-arc basin that was opened by extensional forces associated to roll-back subduction after cessation of spreading activity of the Phoenix Ridge, and the transtension of the westward ending...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Rodrigo,Cristian, Blamey,Jenny M., Huhn,Oliver, Provost,Christine
Lenguaje:English
Publicado: Servicio Nacional de Geología y Minería (SERNAGEOMIN) 2018
Materias:
Acceso en línea:http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062018000300344
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:scielo:S0718-71062018000300344
record_format dspace
spelling oai:scielo:S0718-710620180003003442018-11-05Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?Rodrigo,CristianBlamey,Jenny M.Huhn,OliverProvost,Christine Hydrothermal Helium isotope Thermophiles Seamount Volcanism Rift system Antarctica ABSTRACT The rifting zone of Bransfield Strait, Antarctica, is tectonically and geologically unique. It is a back-arc basin that was opened by extensional forces associated to roll-back subduction after cessation of spreading activity of the Phoenix Ridge, and the transtension of the westward ending of Scotia-Antarctica Plate boundary. The Bransfield Rift/ Ridge is still active generating volcanism or magma rise to force hydrothermal activity. During the ANT-XXV/4 cruise onboard R/V “Polarstern”, standard CTD and beam transmission measurements were done to determine temperature anomaly and turbidity. Water sampling was performed to determine δ3He and to find thermophilic microorganisms to examine the Orca seamount hydrothermal activity. A temperature anomaly of ~0.08 °C, a pick of turbidity, and high value of δ3He (>10%) were found inside Orca seamount. Results are consistent with a hydrothermal flux coming from the seamount. The report of the first observation of thermophilic and hyperthermophilic microorganisms in cold deep Antarctic waters is part of this study. Inside Orca seamount these microorganisms were found at three different depth levels close to the bottom. We suggest that the fluid migration from the volcano resulted from recent magmatic activity and provided the required elemental nutrients for microbial growth. Besides some thermophiles were found outside the seamount in a small quantity close to the seafloor. These would probably be related to subsidiary structures of the Orca seamount, or were transported by currents from other active volcanic sites as Deception Island. The finding of these thermophilic and hyperthermophilic microorganisms raise questions about the dispersal and their resistance in these extreme environments.info:eu-repo/semantics/openAccessServicio Nacional de Geología y Minería (SERNAGEOMIN)Andean geology v.45 n.3 20182018-01-01text/htmlhttp://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062018000300344en10.5027/andgeov45n3-3086
institution Scielo Chile
collection Scielo Chile
language English
topic Hydrothermal
Helium isotope
Thermophiles
Seamount
Volcanism
Rift system
Antarctica
spellingShingle Hydrothermal
Helium isotope
Thermophiles
Seamount
Volcanism
Rift system
Antarctica
Rodrigo,Cristian
Blamey,Jenny M.
Huhn,Oliver
Provost,Christine
Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
description ABSTRACT The rifting zone of Bransfield Strait, Antarctica, is tectonically and geologically unique. It is a back-arc basin that was opened by extensional forces associated to roll-back subduction after cessation of spreading activity of the Phoenix Ridge, and the transtension of the westward ending of Scotia-Antarctica Plate boundary. The Bransfield Rift/ Ridge is still active generating volcanism or magma rise to force hydrothermal activity. During the ANT-XXV/4 cruise onboard R/V “Polarstern”, standard CTD and beam transmission measurements were done to determine temperature anomaly and turbidity. Water sampling was performed to determine δ3He and to find thermophilic microorganisms to examine the Orca seamount hydrothermal activity. A temperature anomaly of ~0.08 °C, a pick of turbidity, and high value of δ3He (>10%) were found inside Orca seamount. Results are consistent with a hydrothermal flux coming from the seamount. The report of the first observation of thermophilic and hyperthermophilic microorganisms in cold deep Antarctic waters is part of this study. Inside Orca seamount these microorganisms were found at three different depth levels close to the bottom. We suggest that the fluid migration from the volcano resulted from recent magmatic activity and provided the required elemental nutrients for microbial growth. Besides some thermophiles were found outside the seamount in a small quantity close to the seafloor. These would probably be related to subsidiary structures of the Orca seamount, or were transported by currents from other active volcanic sites as Deception Island. The finding of these thermophilic and hyperthermophilic microorganisms raise questions about the dispersal and their resistance in these extreme environments.
author Rodrigo,Cristian
Blamey,Jenny M.
Huhn,Oliver
Provost,Christine
author_facet Rodrigo,Cristian
Blamey,Jenny M.
Huhn,Oliver
Provost,Christine
author_sort Rodrigo,Cristian
title Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
title_short Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
title_full Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
title_fullStr Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
title_full_unstemmed Is there an active hydrothermal flux from the Orca seamount in the Bransfield Strait, Antarctica?
title_sort is there an active hydrothermal flux from the orca seamount in the bransfield strait, antarctica?
publisher Servicio Nacional de Geología y Minería (SERNAGEOMIN)
publishDate 2018
url http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-71062018000300344
work_keys_str_mv AT rodrigocristian isthereanactivehydrothermalfluxfromtheorcaseamountinthebransfieldstraitantarctica
AT blameyjennym isthereanactivehydrothermalfluxfromtheorcaseamountinthebransfieldstraitantarctica
AT huhnoliver isthereanactivehydrothermalfluxfromtheorcaseamountinthebransfieldstraitantarctica
AT provostchristine isthereanactivehydrothermalfluxfromtheorcaseamountinthebransfieldstraitantarctica
_version_ 1714205858927214592