Evidence from fluid inclusions for microbial methanogenesis in the early Archaean era

Yuichiro Ueno, Keita Yamada, Naohiro Yoshida, Shigenori Maruyama, Yukio Isozaki

    Research output: Contribution to journalArticlepeer-review

    342 Citations (Scopus)


    Methanogenic microbes may be one of the most primitive organisms 1, although it is uncertain when methanogens first appeared on Earth. During the Archaean era (before 2.5 Gyr ago), methanogens may have been important in regulating climate, because they could have provided sufficient amounts of the greenhouse gas methane to mitigate a severely frozen condition that could have resulted from lower solar luminosity2 during these times. Nevertheless, no direct geological evidence has hitherto been available in support of the existence of methanogens in the Archaean period, although circumstantial evidence is available in the form of ∼2.8-Gyr-old carbon-isotope-depleted kerogen3. Here we report crushing extraction and carbon isotope analysis of methane-bearing fluid inclusions in ∼3.5-Gyr-old hydrothermal precipitates from Pilbara craton, Australia. Our results indicate that the extracted fluids contain microbial methane with carbon isotopic compositions of less than -56‰ included within original precipitates. This provides the oldest evidence of methanogen (>3.46Gyr ago), pre-dating previous geochemical evidence by about 700 million years.

    Original languageEnglish
    Pages (from-to)516-519
    Number of pages4
    Issue number7083
    Publication statusPublished - Mar 23 2006

    ASJC Scopus subject areas

    • General


    Dive into the research topics of 'Evidence from fluid inclusions for microbial methanogenesis in the early Archaean era'. Together they form a unique fingerprint.

    Cite this