Noah J Planavsky, Andrey Bekker, Axel Hofmann, Jeremy D Owens, Timothy W Lyons

2012/11/6

Proceedings of the National Academy of Sciences

109

45

18300-18305

National Acad Sciences

Abstract Carbonates from approximately 2.3–2.1 billion years ago show markedly positive δ
13 C values commonly reaching and sometimes exceeding+ 10‰. Traditional interpretation
of these positive δ 13 C values favors greatly enhanced organic carbon burial on a global
scale, although other researchers have invoked widespread methanogenesis within the
sediments. To resolve between these competing models and, more generally, among the
mechanisms behind Earth's most dramatic carbon isotope event, we obtained coupled ...