Abstract
AbstractGeological sources of H2 and abiotic CH4 have had a critical role in the evolution of our planet and the development of life and sustainability of the deep subsurface biosphere. Yet the origins of these sources are largely unconstrained. Hydration of mantle rocks, or serpentinization, is widely recognized to produce H2 and favour the abiotic genesis of CH4 in shallow settings. However, deeper sources of H2 and abiotic CH4 are missing from current models, which mainly invoke more oxidized fluids at convergent margins. Here we combine data from exhumed subduction zone high-pressure rocks and thermodynamic modelling to show that deep serpentinization (40–80 km) generates significant amounts of H2 and abiotic CH4, as well as H2S and NH3. Our results suggest that subduction, worldwide, hosts large sources of deep H2 and abiotic CH4, potentially providing energy to the overlying subsurface biosphere in the forearc regions of convergent margins.
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy,General Biochemistry, Genetics and Molecular Biology,General Chemistry
Reference90 articles.
1. Colman, D. R., Poudel, S., Stamps, B. W., Boyd, E. S. & Spear, J. R. The deep, hot biosphere: twenty-five years of retrospection. Proc. Natl Acad. Sci. USA 114, 6895–6903 (2017).
2. Barry, P. H. et al. Forearc carbon sink reduces long-term volatile recycling into the mantle. Nature 568, 487–492 (2019).
3. Fullerton, K. M. et al. Plate tectonics drive deep biosphere microbial community composition. Preprint at https://eartharxiv.org/gyr7n/ (2019).
4. Ménez, B. et al. Abiotic synthesis of amino acids in the recesses of the oceanic lithosphere. Nature 564, 59–63 (2018).
5. Glein, C. R., Baross, J. A. & Hunter Waite, J. Jr. The pH of Enceladus’ ocean. Chem. Geol. 162, 202–219 (2015).
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