Abiotic and biotic controls on methane formation down to 2.5 km depth within the Precambrian Fennoscandian Shield
Kietäväinen, R., Ahonen, L., Niinikoski, P., Nykänen, H., & Kukkonen, I. T. (2017). Abiotic and biotic controls on methane formation down to 2.5 km depth within the Precambrian Fennoscandian Shield. Geochimica et Cosmochimica Acta, 202, 124-145. https://doi.org/10.1016/j.gca.2016.12.020
Published in
Geochimica et Cosmochimica ActaAuthors
Date
2017Copyright
© 2016 Elsevier Ltd. This is a final draft version of an article whose final and definitive form has been published by Pergamon. Published in this repository with the kind permission of the publisher.
Despite a geological history characterised by high temperature and pressure processes and organic carbon deprived crystalline bedrock, large amounts of hydrocarbons are found in deep groundwaters within Precambrian continental shields. In many sites, methane comprises more that 80% of the dissolved gas phase reaching concentrations of tens of mmol l−1. In this study, we used isotopic methods to study the carbon isotope systematics and sources of crustal methane within the Fennoscandian Shield. The main study sites were the Outokumpu Deep Drill Hole and the Pyhäsalmi mine in Finland, both of which allow groundwater sampling down to 2.5 km depth and have been previously studied for their groundwater chemistry and microbiology. We show that the differences in the amount and isotopic composition of methane are related to the availability of carbon sources as well as processes behind the incorporation of hydrogen and carbon via abiotic and biotic pathways into hydrocarbon molecules. Supported by previously reported occurrences and isotopic data of deep groundwater methane in lithologically different locations in Finland and Sweden, we show that methane formation is controlled by microbial methanogenesis and abiotic reactions, as well as lithology with the metasedimentary environments being the most favourable for methane occurrence. Rather than a thermogenic relic, crustal methane within the Fennoscandian Shield is more likely the result of low temperature formation from ancient organic compounds or their inorganic intermediates such as graphite. Such crustal gases are characterised by the lack of major amounts of C2+ hydrocarbons and 13C-rich methane. Further, microbiological and isotopic geochemical evidence suggest that microbial methane is more common at depths shallower than 1.5 km.
...
Publisher
Pergamon Press; Geochemical SocietyISSN Search the Publication Forum
0016-7037Keywords
Publication in research information system
https://converis.jyu.fi/converis/portal/detail/Publication/26421127
Metadata
Show full item recordCollections
Related items
Showing items with similar title or keywords.
-
Biotic oxidation of methane in landfills in boreal climatic conditions
Einola, Juha (University of Jyväskylä, 2010)This study focused on the biotic oxidation of methane in landfill covers as a technology for reducing greenhouse gas emissions from landfills, particularly those located in the boreal climatic zone. First, methane oxidation ... -
The influence of lipid content and taxonomic affiliation on methane and carbon dioxide production from phytoplankton biomass in lake sediment
Hiltunen, Minna; Nykänen, Hannu; Syväranta, Jari (John Wiley & Sons, 2021)The greenhouse gases methane (CH4) and carbon dioxide (CO2) are end products of microbial anaerobic degradation of organic matter (OM) in lake sediments. Although previous research has shown that phytoplankton lipid content ... -
Integrating Decomposers, Methane-Cycling Microbes and Ecosystem Carbon Fluxes Along a Peatland Successional Gradient in a Land Uplift Region
Juottonen, Heli; Kieman, Mirkka; Fritze, Hannu; Hamberg, Leena; Laine, Anna M.; Merilä, Päivi; Peltoniemi, Krista; Putkinen, Anuliina; Tuittila, Eeva-Stiina (Springer Science+Business Media, 2022)Peatlands are carbon dioxide (CO2) sinks that, in parallel, release methane (CH4). The peatland carbon (C) balance depends on the interplay of decomposer and CH4-cycling microbes, vegetation, and environmental conditions. ... -
High-resolution spatial patterns and drivers of terrestrial ecosystem carbon dioxide, methane, and nitrous oxide fluxes in the tundra
Virkkala, Anna-Maria; Niittynen, Pekka; Kemppinen, Julia; Marushchak, Maija E.; Voigt, Carolina; Hensgens, Geert; Kerttula, Johanna; Happonen, Konsta; Tyystjärvi, Vilna; Biasi, Christina; Hultman, Jenni; Rinne, Janne; Luoto, Miska (Copernicus GmbH, 2024)Arctic terrestrial greenhouse gas (GHG) fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) play an important role in the global GHG budget. However, these GHG fluxes are rarely studied simultaneously, ... -
Trophic state changes can affect the importance of methane-derived carbon in aquatic food webs
Schilder, Johannes; van Hardenbroek, Maarten; Bodelier, Paul; Kirilova, Emiliya P.; Leuenberger, Markus; Lotter, André F.; Heiri, Oliver (The Royal Society Publishing, 2017)Methane-derived carbon, incorporated by methane-oxidizing bacteria, has been identified as a significant source of carbon in food webs of many lakes. By measuring the stable carbon isotopic composition (δ13C values) of ...