Abstract
Deposition of ferruginous sediment was widespread during the Archaean and Proterozoic Eons, playing an important role in global biogeochemical cycling. Knowledge of organic matter mineralization in such sediment, however, remains mostly conceptual, as modern ferruginous analogs are largely unstudied. Here we show that in sediment of ferruginous Lake Towuti, Indonesia, methanogenesis dominates organic matter mineralization despite highly abundant reactive ferric iron phases like goethite that persist throughout the sediment. Ferric iron can thus be buried over geologic timescales even in the presence of labile organic carbon. Coexistence of ferric iron with millimolar concentrations of methane further demonstrates lack of iron-dependent methane oxidation. With negligible methane oxidation, methane diffuses from the sediment into overlying waters where it can be oxidized with oxygen or escape to the atmosphere. In low-oxygen ferruginous Archaean and Proterozoic oceans, therefore, sedimentary methane production was likely favored with strong potential to influence Earth’s early climate. © 2021, The Author(s).
Original language | English (US) |
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Article number | 2216 |
Number of pages | 9 |
Journal | Nature communications |
Volume | 12 |
Issue number | 1 |
DOIs | |
State | Published - Apr 13 2021 |
Bibliographical note
Funding Information:This research was carried out with partial support from the International Continental Scientific Drilling Program (ICDP), the U.S. National Science Foundation (NSF), the German Research Foundation (DFG), the Swiss National Science Foundation (SNSF), PT Vale Indonesia, the Ministry of Research, Education, and Higher Technology of Indonesia (RISTEK), GFZ German Research Centre for Geosciences, the Natural Sciences and Engineering Research Council of Canada (NSERC), and Genome British Columbia. We thank PT Vale Indonesia, the US Continental Scientific Drilling and Coordination Office, and US National Lacustrine Core Repository, and DOSECC Exploration Services for logistical support. The research was carried out with permissions from RISTEK, the Ministry of Trade of the Republic of Indonesia, the Natural Resources Conservation Center (BKSDA), and the Government of Luwu Timur of Sulawesi. We thank Tri Widiyanto and his staff from Research Center for Limnology, Indonesian Institute of Sciences (LIPI) for their administrative support in obtaining the Scientific Research Permit. Special thanks are due to Jenny Wendt and Xavier Prieto for their assistance during methane analysis. Jan Axel Kitte is acknowledged for his support in the field and in the laboratory.
Publisher Copyright:
© 2021, The Author(s).
Continental Scientific Drilling Facility tags
- TDP
PubMed: MeSH publication types
- Research Support, Non-U.S. Gov't
- Research Support, U.S. Gov't, Non-P.H.S.
- Journal Article