The University of Southampton
University of Southampton Institutional Repository

Submarine hydrothermal venting related to volcanism in the Lesser Antilles: Evidence from ferromanganese precipitates

Record type: Article

Radiogenic isotope compositions (Sr, Nd, Pb, Hf, and Os) of sediment?hosted seafloor ferromanganese crusts and sediments incrusted with ferromanganese oxyhydroxides from the Lesser Antilles island arc were measured to distinguish between hydrogenous (seawater?derived) and hydrothermal metal sources. The ages of the precipitates range between recent (last few thousand years) and a few 100 kyr as deduced from 10Be and Co concentrations. Evidence from the presence of bladed todorokite and nontronite, together with the major element and REE composition, suggests that a significant proportion of these sediment?hosted precipitates formed at relatively low temperatures from a mixture of seawater and hydrothermal fluids associated with island arc volcanism. The radiogenic isotope compositions of all metals mentioned above, except Pb, show large differences in hydrothermal versus hydrogenous contributions over space and time. In contrast to precipitates of high?temperature fluids which mainly scavenge their REE contents from seawater the crusts of this study show 143Nd/144Nd of up to 0.512817 ($\varepsilon$Nd = +3.5). This is close to the signature of the nearby island arc rocks and far above the expected local seawater ratio of ?0.51209 ($\varepsilon$Nd = ?10.7). These crusts also show high 176Hf/177Hf (up to 0.283102), low 87Sr/86Sr (up to 0.7069), and low 187Os/188Os (up to 0.16) compared with local seawater, as expected from hydrothermal, island?arc?derived metal contributions. In contrast, the Pb isotope signatures of the crusts cannot be explained by mixing between seawater and hydrothermal sources. It is suggested that Pb was either removed from the ascending fluids within the sediment column before they reached seawater or the temperatures were too low to leach significant amounts of Pb from the rocks or sediments. External sources such as Saharan dust, particulate inputs from the Orinoco River, or even incongruent release of Pb isotopes from the island arc rock?derived particles must have contributed to the observed Pb isotope variability. Our results suggest that submarine hydrothermalism originating from intraoceanic island arc volcanism creates distinct geochemical environments for the dispersion of hydrothermal fluids and may be an important mechanism to supply metals of hydrothermal origin to seawater.

Full text not available from this repository.

Citation

Frank, M., Marbler, H., Koschinsky, A., de Flierdt, T.V., Klemm, V., Gutjahr, M., Halliday, A.N., Kubik, P.W. and Halbach, P. (2006) Submarine hydrothermal venting related to volcanism in the Lesser Antilles: Evidence from ferromanganese precipitates Geochemistry Geophysics Geosystems, 7, Q04010. (doi:10.1029/2005GC001140).

More information

Published date: 2006

Identifiers

Local EPrints ID: 191631
URI: http://eprints.soton.ac.uk/id/eprint/191631
ISSN: 1525-2027
PURE UUID: bc7e1cd2-00ec-4cc2-8bb6-4d328402b469

Catalogue record

Date deposited: 23 Jun 2011 12:15
Last modified: 18 Jul 2017 11:35

Export record

Altmetrics

Contributors

Author: M. Frank
Author: H. Marbler
Author: A. Koschinsky
Author: T.V. de Flierdt
Author: V. Klemm
Author: M. Gutjahr
Author: A.N. Halliday
Author: P.W. Kubik
Author: P. Halbach

University divisions


Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×