Marine mineral-catalyzed NO and N2O formation on the anoxic early Earth

This is a Preprint and has not been peer reviewed. This is version 2 of this Preprint.


Download Preprint

Supplementary Files

Steffen Buessecker, Hiroshi Imanaka, Tucker Ely, Renyu Hu, Stephen J. Romaniello, Hinsby Cadillo-Quiroz


Microbial metabolisms were limited by available terminal electron acceptors in the anoxic environment of the early Archean. However, iron mineral phases in Fe2+-rich (ferruginous) oceans could have catalyzed reactions with abiotically fixed nitrogen leading to the formation of nitrous oxide (N2O), a potentially favorable terminal electron acceptor. We experimentally simulated anoxic surface-catalyzed reduction of nitrite and nitrate via green rust and magnetite. Besides N2O, we detected and quantified the formation of substantial amounts of nitric oxide (NO). While N2O escaped into the gas phase (63% of nitrite-nitrogen, with green rust as catalyst), NO remained associated with precipitates (7% of nitrite-nitrogen). Using diffusion and photochemical modeling, we show that marine N2O emissions could have sustained atmospheric N2O pools of 1-7 ppb. Although this concentration was insufficient to cause significant warming, the seawater enriched in N2O and NO could have critically affected early benthic life by providing the opportunity to conserve energy.



Earth Sciences, Geochemistry, Physical Sciences and Mathematics


abiotic N2O production, abiotic NO production, Archean ocean, early Earth, green rust, magnetite, mineral catalysis


Published: 2020-08-16 19:47

Older Versions

GNU Lesser General Public License (LGPL) 2.1

Add a Comment

You must log in to post a comment.


There are no comments or no comments have been made public for this article.