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Iron Formation: The Sedimentary Product of a Complex Interplay among Mantle, Tectonic, Oceanic, and Biospheric Processes
Iron formations are economically important sedimentary rocks that are most common in Precambrian sedimentary successions. Although many aspects of their origin remain unresolved, it is widely
Introduction to geomicrobiology
The objective of this monograph was to demonstrate the importance of knowing the phytochemical properties and diversity of microbial metabolism, as a source of infection for other organisms, not necessarily belonging to the same group.
Evidence for oxygenic photosynthesis half a billion years before the Great Oxidation Event
The early Earth was characterized by the absence of oxygen in the ocean–atmosphere system, in contrast to the well-oxygenated conditions that prevail today. Atmospheric concentrations first rose to
Could bacteria have formed the Precambrian banded iron formations
Banded iron formations (BIFs) are prominent sedimentary deposits of the Precambrian, but despite a century of endeavor, the mechanisms of their deposition are still unresolved. Interactions between
Proterozoic ocean redox and biogeochemical stasis
This model suggests that the oceanic Mo reservoir is extremely sensitive to perturbations in the extent of sulfidic seafloor and that the record of Mo and chromium enrichments through time is consistent with the possibility of a Mo–N colimited marine biosphere during many periods of Earth’s history.
Oceanic nickel depletion and a methanogen famine before the Great Oxidation Event
A decline in the molar nickel to iron ratio recorded in banded iron formations is reported, which is attributed to a reduced flux of nickel to the oceans, a consequence of cooling upper-mantle temperatures and decreased eruption of nickel-rich ultramafic rocks at the time.
Deposition of banded iron formations by anoxygenic phototrophic Fe(II)-oxidizing bacteria
The mechanism of banded iron formation (BIF) deposition is controversial, but classically has been interpreted to reflect ferrous iron [Fe(II)] oxidation by molecular oxygen after cyanobacteria
The evolution of the marine phosphate reservoir
There is a peak in phosphorus-to-iron ratios in Neoproterozoic iron formations dating from ∼750 to ∼635 Myr ago, indicating unusually high dissolved phosphate concentrations in the aftermath of widespread, low-latitude ‘snowball Earth’ glaciations.