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

Science Highlights

29 January 2013

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 Fe is truly dissolved. Several other sources supplying dissolved Fe to deep waters (e.g terrestrial Fe input) with a persistent condition in the oxygen minimum zone (OMZ) were also evidenced.

Nishioka_jun_elsevier

Source: Science Direct (click on the image to view it larger)

Reference:

Jun Nishioka, Hajime Obata, Daisuke Tsumune (2013), Evidence of an extensive spread of hydrothermal dissolved iron in the Indian Ocean : Earth and Planetary Science Letters, ELSEVIER (361) p. 26-33, DOI: /10.1016/j.epsl.2012.11.040

Latest highlights

East-West contrasting fate and anthropogenic inputs for dissolved trace metals in the Subarctic Pacific Ocean

Chan and co-authors report the full-depth distribution of dissolved nickel, copper, zinc, and cadmium in the North Pacific Ocean.

Comprehensive quantification of the rare earth element cycle in the northwest Pacific Ocean

Cao and co-authors investigate dissolved rare earth elements and the factors controlling their distributions in the northwest Pacific Ocean.

Iron and zinc isotopes disentangle the anthropogenic, natural and wildfire sources of aerosols over the North and Equatorial Pacific Ocean

Bunnell and co-authors analysed aerosol iron and zinc isotopic compositions along the North Pacific GEOTRACES GP15 section (Alaska-Tahiti).

Contribution of sandy beaches to the oceanic silica cycle

This paper calls into question the commonly accepted idea of an oceanic silicon cycle in equilibrium.

Rechercher