Hydrothermal

Hydrothermalism: a major contributor to the oceanic inventory of dissolved zinc

High-quality dataset of dissolved zinc (Zn) from the US GEOTRACES EPZT cruise (GP16 section) allows Roshan and co-workers (2016, see reference below) to revisit the oceanic budget of dissolved Zn. These investigators have observed a basin-scale transport of mantle-derived dissolved Zn from the hydrothermal vents of the East Pacific Rise to the farfield regions (>4000 […]

Aug / 29 / 2016

Unexpected magnitude of the hydrothermal iron inputs in the deep Pacific

Data from the US GEOTRACES Eastern Pacific Zonal Transect (EPZT, GP16) demonstrate that lateral transport of hydrothermal iron, manganese and aluminium extends up to 4000 km west of the southern East Pacific Ridge, therefore crossing a significant part of the deep Pacific Ocean. The dissolved iron behaves more conservatively than expected, and the resulting flux […]

Jul / 09 / 2015

Dissolved iron sources in the North Atlantic Ocean quantified

The relative importance of four different dissolved iron (Fe) sources in the North Atlantic Ocean have been precisely determined for the first time thanks to GEOTRACES. Using a novel method based on the stable isotopic composition of dissolved Fe, Conway and John (2014, see reference below) have “fingerprinted” different sources of Fe along a section […]

Jul / 02 / 2014

Slow-spreading ridges could be major oceanic iron contributor

A large dissolved iron- and manganese-rich plume has been detected by Saito and co-authors over the slow-spreading southern Mid-Atlantic Ridge. This discovery calls into question the assumption that deep-sea hydrothermal vents along slow-spreading ridges were negligible contributors to the oceanic iron inventory. This result urges reassessment and a likely increase of the contribution of hydrothermal […]

Oct / 30 / 2013

Are the mid oceanic ridges a source of radiogenic neodymium input?

An unexpected radiogenic value of neodymium (Nd) isotopic composition observed by Catherine Jeandel and colleagues in the Deep Pacific Water raises the question of the role of mid ocean ridges in modifying the oceanic Nd signature. GEOTRACES researchers measured three vertical profiles of rare earth element (REE) concentrations and Nd isotopic compositions in the remote […]

Sep / 09 / 2013

Hydrothermalism: A significant dissolved iron source for the deep waters ?

A North-South basin-scale full-depth section profile of dissolved Fe was realized in the Indian Ocean, as part of the first GEOTRACES Japanese cruise (Nov 2009 – Jan 2010). The data clearly show that hydrothermal Fe is distributed over 3000 km distance around a depth of ~ 3000 m, and that a large fraction of this […]

Jan / 29 / 2013

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