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Link to original content: https://pubmed.ncbi.nlm.nih.gov/26236303
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Review
. 2015 Jul 17:6:725.
doi: 10.3389/fmicb.2015.00725. eCollection 2015.

The origin, source, and cycling of methane in deep crystalline rock biosphere

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Review

The origin, source, and cycling of methane in deep crystalline rock biosphere

Riikka Kietäväinen et al. Front Microbiol. .

Abstract

The emerging interest in using stable bedrock formations for industrial purposes, e.g., nuclear waste disposal, has increased the need for understanding microbiological and geochemical processes in deep crystalline rock environments, including the carbon cycle. Considering the origin and evolution of life on Earth, these environments may also serve as windows to the past. Various geological, chemical, and biological processes can influence the deep carbon cycle. Conditions of CH4 formation, available substrates and time scales can be drastically different from surface environments. This paper reviews the origin, source, and cycling of methane in deep terrestrial crystalline bedrock with an emphasis on microbiology. In addition to potential formation pathways of CH4, microbial consumption of CH4 is also discussed. Recent studies on the origin of CH4 in continental bedrock environments have shown that the traditional separation of biotic and abiotic CH4 by the isotopic composition can be misleading in substrate-limited environments, such as the deep crystalline bedrock. Despite of similarities between Precambrian continental sites in Fennoscandia, South Africa and North America, where deep methane cycling has been studied, common physicochemical properties which could explain the variation in the amount of CH4 and presence or absence of CH4 cycling microbes were not found. However, based on their preferred carbon metabolism, methanogenic microbes appeared to have similar spatial distribution among the different sites.

Keywords: Precambrian bedrock; abiotic methane; carbon cycle; deep subsurface; isotopic fractionation; methanogenesis; methanotrophy.

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Figures

Figure 1
Figure 1
Methane cycling scheme in the deep continental biosphere. Methane can originate either from low temperature abiotic reactions in the upper crust, as a gas flux deeper from the crust or mantle or as a result of microbial activity. CO2 and organic matter are common carbon sources, while hydrogen can be derived from breakdown of water in radiolysis, from water-rock interactions or from microbial metabolism. Biological consumption of CH4 can be divided to aerobic and anaerobic methane oxidation, the former being more abundant in shallower depths and the latter in greater depths. Hydrogenotrophic methanogens use inorganic carbon for the production of CH4, as aceticlastic or methylotrophic methanogens use organic carbon molecules, such as formate or acetate. Bacterial fermentation of complex carbon-containing materials, such as kerogen, may produce hydrogen and small organic molecules for methanogens. FTT, Fischer-Tropsch type synthesis of hydrocarbons; ANME archaea, anaerobic methanotrophic archaea.

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References

    1. Ahonen L., Kaija J., Paananen M., Hakkarainen V., Ruskeeniemi T. (2004). Palmottu Natural Analogue: A Summary of the Studies. Geological Survey of Finland, Nuclear Waste Disposal Research, Report YST-121. Available online at: http://tupa.gtk.fi/julkaisu/ydinjate/yst_121.pdf
    1. Anttila P., Ahokas H., Front K., Heikkinen E., Hinkkanen H., Johansson E., et al. (1999). Final Disposal of Spent Nuclear Fuel in Finnish Bedrock - Kivetty Site Report. Posiva report 99-09, Posiva Oy, Olkiluoto. Available online at: http://www.posiva.fi/files/2691/POSIVA-99-09_web.pdf
    1. Arthur M. A., Cole D. R. (2014). Unconventional hydrocarbon resources: prospects and problems. Elements 10, 257–264. 10.2113/gselements.10.4.257 - DOI
    1. Beal E. J., House C. H., Orphan V. J. (2009). Manganese- and iron-dependent marine methane oxidation. Science 325, 184–187. 10.1126/science.1169984 - DOI - PubMed
    1. Bomberg M., Nyyssönen M., Nousiainen A., Hultman J., Paulin L., Auvinen P., et al. (2014). Evaluation of molecular techniques in characterization of deep terrestrial biosphere. Open J. Ecol. 4, 468–487. 10.4236/oje.2014.48040 - DOI

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