Iron formations (IF) represent an iron-rich rock type that typifies many Archaean and
Proterozoic supracrustal successions and are chemical archives of Precambrian seawater …

The sulfur biogeochemical cycle integrates the metabolic activity of multiple microbial
pathways (eg, sulfate reduction, disproportionation, and sulfide oxidation) along with abiotic …

Molecular oxygen (O2) is, and has been, a primary driver of biological evolution and shapes
the contemporary landscape of Earth's biogeochemical cycles. Although “whiffs” of oxygen …

The origin of oxygenic photosynthesis was the most important metabolic innovation in Earth
history. It allowed life to generate energy and reducing power directly from sunlight and …

Construction and assembly of the Geologic Time Scale involves:(a) constructing a relative
(chronostratigraphic) standard scale for key periods in the Earth's rock record;(b) identifying …

Oxidation of manganese (II) to manganese (III, IV) demands oxidants with very high redox
potentials; consequently, manganese oxides are both excellent proxies for molecular …

Oceanic sulfate concentrations are widely thought to have reached millimolar levels during
the Proterozoic Eon, 2.5 to 0.54 billion years ago. Yet the magnitude of the increase in …

The disappearance of mass-independent sulfur isotope fractionation (S-MIF) within the c. 2.3-
billion-year-old (Ga) Rooihoogte Formation has been heralded as a chemostratigraphic …

With growing interest in the application of in situ multiple sulfur isotope analysis to a variety
of mineral systems, we report here the development of a suite of sulfur isotope standards for …

Understanding the timing and trajectory of atmospheric oxygenation remains fundamental to
deciphering its causes and consequences. Given its origin in oxygen-free photochemistry …