Trace element behaviour at cold seeps and the potential export of dissolved iron to the ocean

Lemaitre, Nolwenn
Bayon, Germain
Ondréas, Hélène
Caprais, Jean-Claude
Freslon, Nicolas
Bollinger, Claire
Rouget, Marie-Laure
de Prunelé, Alexis
Ruffine, Livio
Olu-Le Roy, Karine
Sarthou, Géraldine

Open link

Publication date

October 2014

DOI

10.1016/j.epsl.2014.08.014

Publisher

Elsevier BV

Abstract

International audienceSeawater samples were collected by submersible above methane seeps in the Gulf of Guinea (Regab and Baboon pockmarks) in order to investigate the behaviour of iron (Fe), manganese (Mn) and rare earth elements (REE) during fluid seepage. Our aim was to determine whether cold seeps may represent potential sources of dissolved chemical species to the ocean. Dissolved (<0.45 mu m filtered samples) and total dissolvable (unfiltered samples) concentrations were determined over similar to 50 m long vertical transects above the seafloor and at various discrete locations within the pockmarks.We show that substantial amounts of Fe and Mn are released into seawater during seepage of methane-rich fluids. Mn is exported almost quan...