- Abiotic formation of n-alkane hydrocarbons has been postulated to occur within Earth's crust. Apparent evidence was primarily based on uncommon carbon and hydrogen isotope distribution patterns that set methane and its higher chain homologues apart from biotic isotopic compositions associated with microbial production and closed system thermal degradation of organic matter. Here, we present the first global investigation of the carbon and hydrogen isotopic compositions of n-alkanes in volcanic-hydrothermal fluids hosted by basaltic, andesitic, trachytic and rhyolitic rocks. We show that the bulk isotopic compositions of these gases follow trends that are characteristic of high temperature, open system degradation of organic matter. In sediment-free systems, organic matter is supplied by surface waters (seawater, meteoric water) circulating through the reservoir rocks. Our data set strongly implies that thermal degradation of organic matter is able to satisfy isotopic criteria previously classified as being indicative of abiogenesis. Further considering the ubiquitous presence of surface waters in Earth’s crust, abiotic hydrocarbon occurrences might have been significantly overestimated.
MetadatenAuthor: | Jens FiebigORCiDGND, Andri StefánssonORCiDGND, Andrea RicciORCiD, Franco Tassi, Fatima Viveiros, Catarina Silva, Taryn Lopez, Christoph Schreiber, Sven Hofmann, Bruce W. Mountain |
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URN: | urn:nbn:de:hebis:30:3-512579 |
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DOI: | https://doi.org/10.7185/geochemlet.1920 |
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ISSN: | 2410-3403 |
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ISSN: | 2410-339X |
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Parent Title (English): | Geochemical perspectives letters |
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Publisher: | Assoc. |
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Place of publication: | [Paris] |
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Contributor(s): | Liane G. Benning |
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Document Type: | Article |
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Language: | English |
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Year of Completion: | 2019 |
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Date of first Publication: | 2019/07/29 |
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Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
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Release Date: | 2019/09/30 |
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Tag: | abiogenesis; hydrocarbons; volcanic gases |
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Volume: | 11 |
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Page Number: | 5 |
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First Page: | 23 |
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Last Page: | 27 |
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Note: | Published by the European Association of Geochemistry under Creative Commons License CC BY-NC-ND 4.0 |
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HeBIS-PPN: | 454010117 |
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Institutes: | Geowissenschaften / Geographie / Geowissenschaften |
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Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
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Sammlungen: | Universitätspublikationen |
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Open-Access-Publikationsfonds: | Geowissenschaften / Geographie |
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Licence (German): | Creative Commons - Namensnennung-Nicht kommerziell - Keine Bearbeitung 4.0 |
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