The long history of life on Earth has unfolded as a cause-and-effect relationship with the
evolving amount of oxygen (O2) in the oceans and atmosphere. Oxygen deficiency …

Mixed-valent iron [Fe (II)-Fe (III)] minerals such as magnetite and green rust have received a
significant amount of attention over recent decades, especially in the environmental …

The balance between degradation and preservation of sedimentary organic carbon (OC) is
important for global carbon and oxygen cycles. The relative importance of different …

Paleoredox conditions are commonly evaluated based on elemental proxies but, despite
their frequency of use, most of these proxies have received little comparative evaluation or …

Existing redox classifications and the calibrations of elemental proxies to modern
environmental redox scales are in need of re-evaluation. Here, we review environmental …

The rise of atmospheric oxygen fundamentally changed the chemistry of surficial
environments and the nature of Earth's habitability. Early atmospheric oxygenation occurred …

A geologically rapid Neoproterozoic oxygenation event is commonly linked to the
appearance of marine animal groups in the fossil record. However, there is still debate about …

The endosymbiotic origin of mitochondria during eukaryogenesis has long been viewed as
an adaptive response to the oxygenation of Earth's surface environment, presuming a …

The macronutrient phosphorus is thought to limit primary productivity in the oceans on
geological timescales. Although there has been a sustained effort to reconstruct the …

Sedimentary rocks deposited across the Proterozoic–Phanerozoic transition record extreme
climate fluctuations, a potential rise in atmospheric oxygen or re-organization of the seafloor …