Did biogeochemical methane cycling regulate the Neoarchean atmosphere?

This project examines the link between biogenic methane cycling and the formation of a hydrocarbon haze-rich atmosphere on the Neaorchean Earth

The Earth's atmosphere has changed dramatically over geologic history, from an anoxic atmosphere with low oxygen on the early Earth, to the modern oxygen-rich atmosphere capable of supporting macroscopic life as we know it. This project aims to determine how atmospheric chemistry evolved on the run-up to the initial transition to an oxygenated atmosphere. It focuses on the connection between atmospheric chemistry and the biological carbon cycle, through climate and weathering forcings.

In the first year of this project, we have produced high-resolution records of sulfur and carbon isotopes through four separate cores from two continents (South Africa and Western Australia). These records support previous suggestions of a global connection between the biogeochemical carbon and sulfur cycles during the Neoarchean (Zerkle et al., 2012, Nature Geoscience). They further indicate that the Earth's atmosphere was incredibly dynamic and periodically dominated by a hydrocarbon-rich haze on the run-up to the GOE. This work is currently under review in Nature Geoscience (Izon et al., in review, Nature Geoscience).