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

The oxygen content of the Earth's surface environment is thought to have increased in two
broad steps: the Great Oxygenation Event (GOE) around the Archean–Proterozoic boundary …

The composition of sulfur isotopes in sedimentary sulfides and sulfates traces the sulfur
cycle throughout Earth's history. In particular, depletions of sulfur-34 (34S) in sulfide relative …

The secular trend of seawater strontium isotope ratio (87 Sr/86 Sr) reflects changes in the
relative contributions of continental versus mantle reservoirs to ocean composition, and …

Oxygenation of the Earth's surface is increasingly thought to have occurred in two steps. The
first step, which occurred∼ 2,300 million years (Myr) ago, involved a significant increase in …

Phanerozoic levels of atmospheric oxygen relate to the burial histories of organic carbon
and pyrite sulfur. The sulfur cycle remains poorly constrained, however, leading to …

As recognized already by Charles Darwin, animals are geobiological agents. Darwin
observed that worms aerate and mix soils on a massive scale, aiding in the decomposition …

Long-term secular variation in seawater sulfate concentrations ([SO 4 2−] SW) is of interest
owing to its relationship to the oxygenation history of Earth's surface environment. In this …

The global biosphere is commonly assumed to have been less productive before the rise of
complex eukaryotic ecosystems than it is today. However, direct evidence for this assertion …

The distribution of sulfur isotopes in geological materials reveals information about Earth
history and biogeochemical processes. Research during the last several decades has used …